Merge gitlab.com:gitlab-org/gitlab-ce

92 files changed, 2528 insertions, 2034 deletions

diff --git a/lib/gitlab/asciidoc.rb b/lib/gitlab/asciidoc.rb
index bf33e5b1b1e..b203b9d70e4 100644
--- a/lib/gitlab/asciidoc.rb
+++ b/lib/gitlab/asciidoc.rb
@@ -1,14 +1,10 @@
 require 'asciidoctor'
-require 'html/pipeline'
 
 module Gitlab
   # Parser/renderer for the AsciiDoc format that uses Asciidoctor and filters
   # the resulting HTML through HTML pipeline filters.
   module Asciidoc
 
-    # Provide autoload paths for filters to prevent a circular dependency error
-    autoload :RelativeLinkFilter, 'gitlab/markdown/relative_link_filter'
-
     DEFAULT_ADOC_ATTRS = [
       'showtitle', 'idprefix=user-content-', 'idseparator=-', 'env=gitlab',
       'env-gitlab', 'source-highlighter=html-pipeline'
@@ -24,13 +20,11 @@ module Gitlab
     #                 :requested_path
     #                 :ref
     # asciidoc_opts - a Hash of options to pass to the Asciidoctor converter
-    # html_opts     - a Hash of options for HTML output:
-    #                 :xhtml - output XHTML instead of HTML
     #
-    def self.render(input, context, asciidoc_opts = {}, html_opts = {})
-      asciidoc_opts = asciidoc_opts.reverse_merge(
+    def self.render(input, context, asciidoc_opts = {})
+      asciidoc_opts.reverse_merge!(
         safe: :secure,
-        backend: html_opts[:xhtml] ? :xhtml5 : :html5,
+        backend: :html5,
         attributes: []
       )
       asciidoc_opts[:attributes].unshift(*DEFAULT_ADOC_ATTRS)
@@ -38,23 +32,10 @@ module Gitlab
       html = ::Asciidoctor.convert(input, asciidoc_opts)
 
       if context[:project]
-        result = HTML::Pipeline.new(filters).call(html, context)
-
-        save_opts = html_opts[:xhtml] ?
-          Nokogiri::XML::Node::SaveOptions::AS_XHTML : 0
-
-        html = result[:output].to_html(save_with: save_opts)
+        html = Banzai.render(html, context.merge(pipeline: :asciidoc))
       end
 
       html.html_safe
     end
-
-    private
-
-    def self.filters
-      [
-        Gitlab::Markdown::RelativeLinkFilter
-      ]
-    end
   end
 end
diff --git a/lib/gitlab/backend/grack_auth.rb b/lib/gitlab/backend/grack_auth.rb
index 6830a916bcb..cdcaae8094c 100644
--- a/lib/gitlab/backend/grack_auth.rb
+++ b/lib/gitlab/backend/grack_auth.rb
@@ -33,8 +33,11 @@ module Grack
 
       auth!
 
+      lfs_response = Gitlab::Lfs::Router.new(project, @user, @request).try_call
+      return lfs_response unless lfs_response.nil?
+
       if project && authorized_request?
-        # Tell gitlab-git-http-server the request is OK, and what the GL_ID is
+        # Tell gitlab-workhorse the request is OK, and what the GL_ID is
         render_grack_auth_ok
       elsif @user.nil? && !@ci
         unauthorized
@@ -72,9 +75,11 @@ module Grack
       matched_login = /(?<s>^[a-zA-Z]*-ci)-token$/.match(login)
 
       if project && matched_login.present? && git_cmd == 'git-upload-pack'
-        underscored_service = matched_login['s'].underscore 
+        underscored_service = matched_login['s'].underscore
 
-        if Service.available_services_names.include?(underscored_service)
+        if underscored_service == 'gitlab_ci'
+          return project && project.valid_build_token?(password)
+        elsif Service.available_services_names.include?(underscored_service)
           service_method = "#{underscored_service}_service"
           service = project.send(service_method)
 
@@ -193,12 +198,19 @@ module Grack
     end
 
     def render_grack_auth_ok
+      repo_path =
+        if @request.path_info =~ /^([\w\.\/-]+)\.wiki\.git/
+          ProjectWiki.new(project).repository.path_to_repo
+        else
+          project.repository.path_to_repo
+        end
+
       [
         200,
         { "Content-Type" => "application/json" },
         [JSON.dump({
           'GL_ID' => Gitlab::ShellEnv.gl_id(@user),
-          'RepoPath' => project.repository.path_to_repo,
+          'RepoPath' => repo_path,
         })]
       ]
     end
diff --git a/lib/gitlab/backend/shell.rb b/lib/gitlab/backend/shell.rb
index 59f7a45b791..4c15d58d680 100644
--- a/lib/gitlab/backend/shell.rb
+++ b/lib/gitlab/backend/shell.rb
@@ -1,8 +1,8 @@
 module Gitlab
   class Shell
-    class AccessDenied < StandardError; end
+    class Error < StandardError; end
 
-    class KeyAdder < Struct.new(:io)
+    KeyAdder = Struct.new(:io) do
       def add_key(id, key)
         key.gsub!(/[[:space:]]+/, ' ').strip!
         io.puts("#{id}\t#{key}")
@@ -36,8 +36,9 @@ module Gitlab
     #   import_repository("gitlab/gitlab-ci", "https://github.com/randx/six.git")
     #
     def import_repository(name, url)
-      Gitlab::Utils.system_silent([gitlab_shell_projects_path, 'import-project',
-                                   "#{name}.git", url, '240'])
+      output, status = Popen::popen([gitlab_shell_projects_path, 'import-project', "#{name}.git", url, '240'])
+      raise Error, output unless status.zero?
+      true
     end
 
     # Move repository
diff --git a/lib/gitlab/bitbucket_import/project_creator.rb b/lib/gitlab/bitbucket_import/project_creator.rb
index 35e34d033e0..03aac1a025a 100644
--- a/lib/gitlab/bitbucket_import/project_creator.rb
+++ b/lib/gitlab/bitbucket_import/project_creator.rb
@@ -11,7 +11,8 @@ module Gitlab
       end
 
       def execute
-        project = ::Projects::CreateService.new(current_user,
+        project = ::Projects::CreateService.new(
+          current_user,
           name: repo["name"],
           path: repo["slug"],
           description: repo["description"],
diff --git a/lib/gitlab/blacklist.rb b/lib/gitlab/blacklist.rb
deleted file mode 100644
index 43145e0ee1b..00000000000
--- a/lib/gitlab/blacklist.rb
+++ /dev/null
@@ -1,34 +0,0 @@
-module Gitlab
-  module Blacklist
-    extend self
-
-    def path
-      %w(
-        admin
-        dashboard
-        files
-        groups
-        help
-        profile
-        projects
-        search
-        public
-        assets
-        u
-        s
-        teams
-        merge_requests
-        issues
-        users
-        snippets
-        services
-        repository
-        hooks
-        notes
-        unsubscribes
-        all
-        ci
-      )
-    end
-  end
-end
diff --git a/lib/gitlab/build_data_builder.rb b/lib/gitlab/build_data_builder.rb
new file mode 100644
index 00000000000..86bfa0a4378
--- /dev/null
+++ b/lib/gitlab/build_data_builder.rb
@@ -0,0 +1,64 @@
+module Gitlab
+  class BuildDataBuilder
+    class << self
+      def build(build)
+        project = build.project
+        commit = build.commit
+        user = build.user
+
+        data = {
+          object_kind: 'build',
+
+          ref: build.ref,
+          tag: build.tag,
+          before_sha: build.before_sha,
+          sha: build.sha,
+
+          # TODO: should this be not prefixed with build_?
+          # Leaving this way to have backward compatibility
+          build_id: build.id,
+          build_name: build.name,
+          build_stage: build.stage,
+          build_status: build.status,
+          build_started_at: build.started_at,
+          build_finished_at: build.finished_at,
+          build_duration: build.duration,
+
+          # TODO: do we still need it?
+          project_id: project.id,
+          project_name: project.name_with_namespace,
+
+          user: {
+            id: user.try(:id),
+            name: user.try(:name),
+            email: user.try(:email),
+          },
+
+          commit: {
+            id: commit.id,
+            sha: commit.sha,
+            message: commit.git_commit_message,
+            author_name: commit.git_author_name,
+            author_email: commit.git_author_email,
+            status: commit.status,
+            duration: commit.duration,
+            started_at: commit.started_at,
+            finished_at: commit.finished_at,
+          },
+
+          repository: {
+            name: project.name,
+            url: project.url_to_repo,
+            description: project.description,
+            homepage: project.web_url,
+            git_http_url: project.http_url_to_repo,
+            git_ssh_url: project.ssh_url_to_repo,
+            visibility_level: project.visibility_level
+          },
+        }
+
+        data
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/closing_issue_extractor.rb b/lib/gitlab/closing_issue_extractor.rb
index aeec595782c..9bef9037ad6 100644
--- a/lib/gitlab/closing_issue_extractor.rb
+++ b/lib/gitlab/closing_issue_extractor.rb
@@ -1,6 +1,12 @@
 module Gitlab
   class ClosingIssueExtractor
-    ISSUE_CLOSING_REGEX = Regexp.new(Gitlab.config.gitlab.issue_closing_pattern)
+    ISSUE_CLOSING_REGEX = begin
+      link_pattern = URI.regexp(%w(http https))
+
+      pattern = Gitlab.config.gitlab.issue_closing_pattern
+      pattern = pattern.sub('%{issue_ref}', "(?:(?:#{link_pattern})|(?:#{Issue.reference_pattern}))")
+      Regexp.new(pattern).freeze
+    end
 
     def initialize(project, current_user = nil)
       @extractor = Gitlab::ReferenceExtractor.new(project, current_user)
@@ -9,10 +15,12 @@ module Gitlab
     def closed_by_message(message)
       return [] if message.nil?
 
-      closing_statements = message.scan(ISSUE_CLOSING_REGEX).
-        map { |ref| ref[0] }.join(" ")
+      closing_statements = []
+      message.scan(ISSUE_CLOSING_REGEX) do
+        closing_statements << Regexp.last_match[0]
+      end
 
-      @extractor.analyze(closing_statements)
+      @extractor.analyze(closing_statements.join(" "))
 
       @extractor.issues
     end
diff --git a/lib/gitlab/compare_result.rb b/lib/gitlab/compare_result.rb
index d72391dade5..0d696a1ee28 100644
--- a/lib/gitlab/compare_result.rb
+++ b/lib/gitlab/compare_result.rb
@@ -2,8 +2,8 @@ module Gitlab
   class CompareResult
     attr_reader :commits, :diffs
 
-    def initialize(compare)
-      @commits, @diffs = compare.commits, compare.diffs
+    def initialize(compare, diff_options = {})
+      @commits, @diffs = compare.commits, compare.diffs(nil, diff_options)
     end
   end
 end
diff --git a/lib/gitlab/contributions_calendar.rb b/lib/gitlab/contributions_calendar.rb
index 8a7f8dc5003..85583dce9ee 100644
--- a/lib/gitlab/contributions_calendar.rb
+++ b/lib/gitlab/contributions_calendar.rb
@@ -45,11 +45,11 @@ module Gitlab
     end
 
     def starting_year
-      (Time.now - 1.year).strftime("%Y")
+      1.year.ago.year
     end
 
     def starting_month
-      Date.today.strftime("%m").to_i
+      Date.today.month
     end
   end
 end
diff --git a/lib/gitlab/current_settings.rb b/lib/gitlab/current_settings.rb
index 0ea1b6a2f6f..7a86c09158e 100644
--- a/lib/gitlab/current_settings.rb
+++ b/lib/gitlab/current_settings.rb
@@ -23,7 +23,9 @@ module Gitlab
         restricted_visibility_levels: Settings.gitlab['restricted_visibility_levels'],
         max_attachment_size: Settings.gitlab['max_attachment_size'],
         session_expire_delay: Settings.gitlab['session_expire_delay'],
-        import_sources: Settings.gitlab['import_sources']
+        import_sources: Settings.gitlab['import_sources'],
+        shared_runners_enabled: Settings.gitlab_ci['shared_runners_enabled'],
+        max_artifacts_size: Settings.artifacts['max_size'],
       )
     end
 
@@ -36,7 +38,9 @@ module Gitlab
                  true
                end
 
-      use_db && ActiveRecord::Base.connection.active? && ActiveRecord::Base.connection.table_exists?('application_settings')
+      use_db && ActiveRecord::Base.connection.active? &&
+                !ActiveRecord::Migrator.needs_migration? &&
+                ActiveRecord::Base.connection.table_exists?('application_settings')
     end
   end
 end
diff --git a/lib/gitlab/database.rb b/lib/gitlab/database.rb
index 741a52714ac..de77a6fbff1 100644
--- a/lib/gitlab/database.rb
+++ b/lib/gitlab/database.rb
@@ -1,11 +1,29 @@
 module Gitlab
   module Database
     def self.mysql?
-      ActiveRecord::Base.connection.adapter_name.downcase == 'mysql'
+      ActiveRecord::Base.connection.adapter_name.downcase == 'mysql2'
     end
 
     def self.postgresql?
       ActiveRecord::Base.connection.adapter_name.downcase == 'postgresql'
     end
+
+    def true_value
+      case ActiveRecord::Base.connection.adapter_name.downcase
+      when 'postgresql'
+        "'t'"
+      else
+        1
+      end
+    end
+
+    def false_value
+      case ActiveRecord::Base.connection.adapter_name.downcase
+      when 'postgresql'
+        "'f'"
+      else
+        0
+      end
+    end
   end
 end
diff --git a/lib/gitlab/diff/file.rb b/lib/gitlab/diff/file.rb
index 142058aa69d..79061cd0141 100644
--- a/lib/gitlab/diff/file.rb
+++ b/lib/gitlab/diff/file.rb
@@ -46,11 +46,11 @@ module Gitlab
       end
 
       def added_lines
-        diff_lines.select(&:added?).size
+        diff_lines.count(&:added?)
       end
 
       def removed_lines
-        diff_lines.select(&:removed?).size
+        diff_lines.count(&:removed?)
       end
     end
   end
diff --git a/lib/gitlab/email/message/repository_push.rb b/lib/gitlab/email/message/repository_push.rb
new file mode 100644
index 00000000000..a2eb7a70bd2
--- /dev/null
+++ b/lib/gitlab/email/message/repository_push.rb
@@ -0,0 +1,137 @@
+module Gitlab
+  module Email
+    module Message
+      class RepositoryPush
+        attr_accessor :recipient
+        attr_reader :author_id, :ref, :action
+
+        include Gitlab::Application.routes.url_helpers
+
+        delegate :namespace, :name_with_namespace, to: :project, prefix: :project
+        delegate :name, to: :author, prefix: :author
+
+        def initialize(notify, project_id, recipient, opts = {})
+          raise ArgumentError, 'Missing options: author_id, ref, action' unless
+            opts[:author_id] && opts[:ref] && opts[:action]
+
+          @notify = notify
+          @project_id = project_id
+          @recipient = recipient
+          @opts = opts.dup
+
+          @author_id = @opts.delete(:author_id)
+          @ref = @opts.delete(:ref)
+          @action = @opts.delete(:action)
+        end
+
+        def project
+          @project ||= Project.find(@project_id)
+        end
+
+        def author
+          @author ||= User.find(@author_id)
+        end
+
+        def commits
+          @commits ||= (Commit.decorate(compare.commits, project) if compare)
+        end
+
+        def diffs
+          @diffs ||= (compare.diffs if compare)
+        end
+
+        def diffs_count
+          diffs.count if diffs
+        end
+
+        def compare
+          @opts[:compare]
+        end
+
+        def compare_timeout
+          compare.timeout if compare
+        end
+
+        def reverse_compare?
+          @opts[:reverse_compare] || false
+        end
+
+        def disable_diffs?
+          @opts[:disable_diffs] || false
+        end
+
+        def send_from_committer_email?
+          @opts[:send_from_committer_email] || false
+        end
+
+        def action_name
+          @action_name ||=
+            case @action
+            when :create
+              'pushed new'
+            when :delete
+              'deleted'
+            else
+              'pushed to'
+            end
+        end
+
+        def ref_name
+          @ref_name ||= Gitlab::Git.ref_name(@ref)
+        end
+
+        def ref_type
+          @ref_type ||= Gitlab::Git.tag_ref?(@ref) ? 'tag' : 'branch'
+        end
+
+        def target_url
+          if @action == :push && commits
+            if commits.length > 1
+              namespace_project_compare_url(project_namespace,
+                                            project,
+                                            from: Commit.new(compare.base, project),
+                                            to:   Commit.new(compare.head, project))
+            else
+              namespace_project_commit_url(project_namespace,
+                                           project, commits.first)
+            end
+          else
+            unless @action == :delete
+              namespace_project_tree_url(project_namespace,
+                                         project, ref_name)
+            end
+          end
+        end
+
+        def reply_to
+          if send_from_committer_email? && @notify.can_send_from_user_email?(author)
+            author.email
+          else
+            Gitlab.config.gitlab.email_reply_to
+          end
+        end
+
+        def subject
+          subject_text = '[Git]'
+          subject_text << "[#{project.path_with_namespace}]"
+          subject_text << "[#{ref_name}]" if @action == :push
+          subject_text << ' '
+
+          if @action == :push && commits
+            if commits.length > 1
+              subject_text << "Deleted " if reverse_compare?
+              subject_text << "#{commits.length} commits: #{commits.first.title}"
+            else
+              subject_text << "Deleted 1 commit: " if reverse_compare?
+              subject_text << commits.first.title
+            end
+          else
+            subject_action = action_name.dup
+            subject_action[0] = subject_action[0].capitalize
+            subject_text << "#{subject_action} #{ref_type} #{ref_name}"
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/fogbugz_import/importer.rb b/lib/gitlab/fogbugz_import/importer.rb
index 496256700b8..403ebeec474 100644
--- a/lib/gitlab/fogbugz_import/importer.rb
+++ b/lib/gitlab/fogbugz_import/importer.rb
@@ -199,7 +199,7 @@ module Gitlab
         s = s.gsub(/^#/, "\\#")
         s = s.gsub(/^-/, "\\-")
         s = s.gsub("`", "\\~")
-        s = s.gsub("\r", "")
+        s = s.delete("\r")
         s = s.gsub("\n", "  \n")
         s
       end
diff --git a/lib/gitlab/fogbugz_import/project_creator.rb b/lib/gitlab/fogbugz_import/project_creator.rb
index 8b1b6f48ed5..e0163499e30 100644
--- a/lib/gitlab/fogbugz_import/project_creator.rb
+++ b/lib/gitlab/fogbugz_import/project_creator.rb
@@ -12,7 +12,8 @@ module Gitlab
       end
 
       def execute
-        project = ::Projects::CreateService.new(current_user,
+        project = ::Projects::CreateService.new(
+          current_user,
           name: repo.safe_name,
           path: repo.path,
           namespace: namespace,
diff --git a/lib/gitlab/force_push_check.rb b/lib/gitlab/force_push_check.rb
index fdb6a35c78d..93c6a5bb7f5 100644
--- a/lib/gitlab/force_push_check.rb
+++ b/lib/gitlab/force_push_check.rb
@@ -7,7 +7,7 @@ module Gitlab
       if Gitlab::Git.blank_ref?(oldrev) || Gitlab::Git.blank_ref?(newrev)
         false
       else
-        missed_refs, _ = Gitlab::Popen.popen(%W(git --git-dir=#{project.repository.path_to_repo} rev-list #{oldrev} ^#{newrev}))
+        missed_refs, _ = Gitlab::Popen.popen(%W(#{Gitlab.config.git.bin_path} --git-dir=#{project.repository.path_to_repo} rev-list #{oldrev} ^#{newrev}))
         missed_refs.split("\n").size > 0
       end
     end
diff --git a/lib/gitlab/git.rb b/lib/gitlab/git.rb
index 0c350d7c675..f065cc5e9e9 100644
--- a/lib/gitlab/git.rb
+++ b/lib/gitlab/git.rb
@@ -20,6 +20,10 @@ module Gitlab
       def blank_ref?(ref)
         ref == BLANK_SHA
       end
+
+      def version
+        Gitlab::VersionInfo.parse(Gitlab::Popen.popen(%W(#{Gitlab.config.git.bin_path} --version)).first)
+      end
     end
   end
 end
diff --git a/lib/gitlab/git/hook.rb b/lib/gitlab/git/hook.rb
index dd393fe09d2..07b856ca64c 100644
--- a/lib/gitlab/git/hook.rb
+++ b/lib/gitlab/git/hook.rb
@@ -16,6 +16,17 @@ module Gitlab
       def trigger(gl_id, oldrev, newrev, ref)
         return true unless exists?
 
+        case name
+        when "pre-receive", "post-receive"
+          call_receive_hook(gl_id, oldrev, newrev, ref)
+        when "update"
+          call_update_hook(gl_id, oldrev, newrev, ref)
+        end
+      end
+
+      private
+
+      def call_receive_hook(gl_id, oldrev, newrev, ref)
         changes = [oldrev, newrev, ref].join(" ")
 
         # function  will return true if succesful
@@ -54,6 +65,12 @@ module Gitlab
 
         exit_status
       end
+
+      def call_update_hook(gl_id, oldrev, newrev, ref)
+        Dir.chdir(repo_path) do
+          system({ 'GL_ID' => gl_id }, path, ref, oldrev, newrev)
+        end
+      end
     end
   end
 end
diff --git a/lib/gitlab/git_access.rb b/lib/gitlab/git_access.rb
index c90184d31cf..3ed1eec517c 100644
--- a/lib/gitlab/git_access.rb
+++ b/lib/gitlab/git_access.rb
@@ -13,7 +13,7 @@ module Gitlab
     def user
       return @user if defined?(@user)
 
-      @user = 
+      @user =
         case actor
         when User
           actor
@@ -125,7 +125,7 @@ module Gitlab
     def change_access_check(change)
       oldrev, newrev, ref = change.split(' ')
 
-      action = 
+      action =
         if project.protected_branch?(branch_name(ref))
           protected_branch_action(oldrev, newrev, branch_name(ref))
         elsif protected_tag?(tag_name(ref))
@@ -148,7 +148,7 @@ module Gitlab
             build_status_object(false, "You are not allowed to change existing tags on this project.")
           else # :push_code
             build_status_object(false, "You are not allowed to push code to this project.")
-          end 
+          end
         return status
       end
 
diff --git a/lib/gitlab/git_ref_validator.rb b/lib/gitlab/git_ref_validator.rb
index 39d17def930..4d83d8e72a8 100644
--- a/lib/gitlab/git_ref_validator.rb
+++ b/lib/gitlab/git_ref_validator.rb
@@ -6,7 +6,7 @@ module Gitlab
     # Returns true for a valid reference name, false otherwise
     def validate(ref_name)
       Gitlab::Utils.system_silent(
-        %W(git check-ref-format refs/#{ref_name}))
+        %W(#{Gitlab.config.git.bin_path} check-ref-format refs/#{ref_name}))
     end
   end
 end
diff --git a/lib/gitlab/github_import/base_formatter.rb b/lib/gitlab/github_import/base_formatter.rb
new file mode 100644
index 00000000000..202263c6742
--- /dev/null
+++ b/lib/gitlab/github_import/base_formatter.rb
@@ -0,0 +1,21 @@
+module Gitlab
+  module GithubImport
+    class BaseFormatter
+      attr_reader :formatter, :project, :raw_data
+
+      def initialize(project, raw_data)
+        @project = project
+        @raw_data = raw_data
+        @formatter = Gitlab::ImportFormatter.new
+      end
+
+      private
+
+      def gl_user_id(github_id)
+        User.joins(:identities).
+          find_by("identities.extern_uid = ? AND identities.provider = 'github'", github_id.to_s).
+          try(:id)
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/github_import/client.rb b/lib/gitlab/github_import/client.rb
index 270cbcd9ccd..74d1529e1ff 100644
--- a/lib/gitlab/github_import/client.rb
+++ b/lib/gitlab/github_import/client.rb
@@ -46,7 +46,7 @@ module Gitlab
       end
 
       def github_options
-        OmniAuth::Strategies::GitHub.default_options[:client_options].symbolize_keys
+        OmniAuth::Strategies::GitHub.default_options[:client_options].to_h.symbolize_keys
       end
     end
   end
diff --git a/lib/gitlab/github_import/comment_formatter.rb b/lib/gitlab/github_import/comment_formatter.rb
new file mode 100644
index 00000000000..7d58e53991a
--- /dev/null
+++ b/lib/gitlab/github_import/comment_formatter.rb
@@ -0,0 +1,45 @@
+module Gitlab
+  module GithubImport
+    class CommentFormatter < BaseFormatter
+      def attributes
+        {
+          project: project,
+          note: note,
+          commit_id: raw_data.commit_id,
+          line_code: line_code,
+          author_id: author_id,
+          created_at: raw_data.created_at,
+          updated_at: raw_data.updated_at
+        }
+      end
+
+      private
+
+      def author
+        raw_data.user.login
+      end
+
+      def author_id
+        gl_user_id(raw_data.user.id) || project.creator_id
+      end
+
+      def body
+        raw_data.body || ""
+      end
+
+      def line_code
+        if on_diff?
+          Gitlab::Diff::LineCode.generate(raw_data.path, raw_data.position, 0)
+        end
+      end
+
+      def on_diff?
+        raw_data.path && raw_data.position
+      end
+
+      def note
+        formatter.author_line(author) + body
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/github_import/importer.rb b/lib/gitlab/github_import/importer.rb
index bd7340a80f1..2b0afbc7b39 100644
--- a/lib/gitlab/github_import/importer.rb
+++ b/lib/gitlab/github_import/importer.rb
@@ -12,39 +12,59 @@ module Gitlab
       end
 
       def execute
-        #Issues && Comments
+        import_issues
+        import_pull_requests
+
+        true
+      end
+
+      private
+
+      def import_issues
         client.list_issues(project.import_source, state: :all,
                                                   sort: :created,
-                                                  direction: :asc).each do |issue|
-          if issue.pull_request.nil?
-
-            body = @formatter.author_line(issue.user.login)
-            body += issue.body
+                                                  direction: :asc).each do |raw_data|
+          gh_issue = IssueFormatter.new(project, raw_data)
 
-            if issue.comments > 0
-              body += @formatter.comments_header
+          if gh_issue.valid?
+            issue = Issue.create!(gh_issue.attributes)
 
-              client.issue_comments(project.import_source, issue.number).each do |c|
-                body += @formatter.comment(c.user.login, c.created_at, c.body)
-              end
+            if gh_issue.has_comments?
+              import_comments(gh_issue.number, issue)
             end
+          end
+        end
+      end
+
+      def import_pull_requests
+        client.pull_requests(project.import_source, state: :all,
+                                                    sort: :created,
+                                                    direction: :asc).each do |raw_data|
+          pull_request = PullRequestFormatter.new(project, raw_data)
 
-            project.issues.create!(
-              description: body,
-              title: issue.title,
-              state: issue.state == 'closed' ? 'closed' : 'opened',
-              author_id: gl_user_id(project, issue.user.id)
-            )
+          if !pull_request.cross_project? && pull_request.valid?
+            merge_request = MergeRequest.create!(pull_request.attributes)
+            import_comments(pull_request.number, merge_request)
+            import_comments_on_diff(pull_request.number, merge_request)
           end
         end
       end
 
-      private
+      def import_comments(issue_number, noteable)
+        comments = client.issue_comments(project.import_source, issue_number)
+        create_comments(comments, noteable)
+      end
 
-      def gl_user_id(project, github_id)
-        user = User.joins(:identities).
-          find_by("identities.extern_uid = ? AND identities.provider = 'github'", github_id.to_s)
-        (user && user.id) || project.creator_id
+      def import_comments_on_diff(pull_request_number, merge_request)
+        comments = client.pull_request_comments(project.import_source, pull_request_number)
+        create_comments(comments, merge_request)
+      end
+
+      def create_comments(comments, noteable)
+        comments.each do |raw_data|
+          comment = CommentFormatter.new(project, raw_data)
+          noteable.notes.create!(comment.attributes)
+        end
       end
     end
   end
diff --git a/lib/gitlab/github_import/issue_formatter.rb b/lib/gitlab/github_import/issue_formatter.rb
new file mode 100644
index 00000000000..1e3ba44f27c
--- /dev/null
+++ b/lib/gitlab/github_import/issue_formatter.rb
@@ -0,0 +1,66 @@
+module Gitlab
+  module GithubImport
+    class IssueFormatter < BaseFormatter
+      def attributes
+        {
+          project: project,
+          title: raw_data.title,
+          description: description,
+          state: state,
+          author_id: author_id,
+          assignee_id: assignee_id,
+          created_at: raw_data.created_at,
+          updated_at: updated_at
+        }
+      end
+
+      def has_comments?
+        raw_data.comments > 0
+      end
+
+      def number
+        raw_data.number
+      end
+
+      def valid?
+        raw_data.pull_request.nil?
+      end
+
+      private
+
+      def assigned?
+        raw_data.assignee.present?
+      end
+
+      def assignee_id
+        if assigned?
+          gl_user_id(raw_data.assignee.id)
+        end
+      end
+
+      def author
+        raw_data.user.login
+      end
+
+      def author_id
+        gl_user_id(raw_data.user.id) || project.creator_id
+      end
+
+      def body
+        raw_data.body || ""
+      end
+
+      def description
+        @formatter.author_line(author) + body
+      end
+
+      def state
+        raw_data.state == 'closed' ? 'closed' : 'opened'
+      end
+
+      def updated_at
+        state == 'closed' ? raw_data.closed_at : raw_data.updated_at
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/github_import/pull_request_formatter.rb b/lib/gitlab/github_import/pull_request_formatter.rb
new file mode 100644
index 00000000000..b7c47958cc7
--- /dev/null
+++ b/lib/gitlab/github_import/pull_request_formatter.rb
@@ -0,0 +1,101 @@
+module Gitlab
+  module GithubImport
+    class PullRequestFormatter < BaseFormatter
+      def attributes
+        {
+          title: raw_data.title,
+          description: description,
+          source_project: source_project,
+          source_branch: source_branch.name,
+          target_project: target_project,
+          target_branch: target_branch.name,
+          state: state,
+          author_id: author_id,
+          assignee_id: assignee_id,
+          created_at: raw_data.created_at,
+          updated_at: updated_at
+        }
+      end
+
+      def cross_project?
+        source_repo.fork == true
+      end
+
+      def number
+        raw_data.number
+      end
+
+      def valid?
+        source_branch.present? && target_branch.present?
+      end
+
+      private
+
+      def assigned?
+        raw_data.assignee.present?
+      end
+
+      def assignee_id
+        if assigned?
+          gl_user_id(raw_data.assignee.id)
+        end
+      end
+
+      def author
+        raw_data.user.login
+      end
+
+      def author_id
+        gl_user_id(raw_data.user.id) || project.creator_id
+      end
+
+      def body
+        raw_data.body || ""
+      end
+
+      def description
+        formatter.author_line(author) + body
+      end
+
+      def source_project
+        project
+      end
+
+      def source_repo
+        raw_data.head.repo
+      end
+
+      def source_branch
+        source_project.repository.find_branch(raw_data.head.ref)
+      end
+
+      def target_project
+        project
+      end
+
+      def target_branch
+        target_project.repository.find_branch(raw_data.base.ref)
+      end
+
+      def state
+        @state ||= case true
+                   when raw_data.state == 'closed' && raw_data.merged_at.present?
+                     'merged'
+                   when raw_data.state == 'closed'
+                     'closed'
+                   else
+                     'opened'
+                   end
+      end
+
+      def updated_at
+        case state
+        when 'merged' then raw_data.merged_at
+        when 'closed' then raw_data.closed_at
+        else
+          raw_data.updated_at
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/gitlab_import/client.rb b/lib/gitlab/gitlab_import/client.rb
index 9c00896c913..86fb6c51765 100644
--- a/lib/gitlab/gitlab_import/client.rb
+++ b/lib/gitlab/gitlab_import/client.rb
@@ -75,7 +75,7 @@ module Gitlab
       end
 
       def gitlab_options
-        OmniAuth::Strategies::GitLab.default_options[:client_options].symbolize_keys
+        OmniAuth::Strategies::GitLab.default_options[:client_options].to_h.symbolize_keys
       end
     end
   end
diff --git a/lib/gitlab/gitlab_import/project_creator.rb b/lib/gitlab/gitlab_import/project_creator.rb
index d9452de6a50..7baaadb813c 100644
--- a/lib/gitlab/gitlab_import/project_creator.rb
+++ b/lib/gitlab/gitlab_import/project_creator.rb
@@ -11,7 +11,8 @@ module Gitlab
       end
 
       def execute
-        project = ::Projects::CreateService.new(current_user,
+        project = ::Projects::CreateService.new(
+          current_user,
           name: repo["name"],
           path: repo["path"],
           description: repo["description"],
diff --git a/lib/gitlab/gitorious_import/project_creator.rb b/lib/gitlab/gitorious_import/project_creator.rb
index cc9a91c91f4..8e22aa9286d 100644
--- a/lib/gitlab/gitorious_import/project_creator.rb
+++ b/lib/gitlab/gitorious_import/project_creator.rb
@@ -10,7 +10,8 @@ module Gitlab
       end
 
       def execute
-        ::Projects::CreateService.new(current_user,
+        ::Projects::CreateService.new(
+          current_user,
           name: repo.name,
           path: repo.path,
           description: repo.description,
diff --git a/lib/gitlab/google_code_import/importer.rb b/lib/gitlab/google_code_import/importer.rb
index 03c410726a5..62da327931f 100644
--- a/lib/gitlab/google_code_import/importer.rb
+++ b/lib/gitlab/google_code_import/importer.rb
@@ -30,7 +30,7 @@ module Gitlab
 
       def user_map
         @user_map ||= begin
-          user_map = Hash.new do |hash, user| 
+          user_map = Hash.new do |hash, user|
             # Replace ... by \.\.\., so `johnsm...@gmail.com` isn't autolinked.
             Client.mask_email(user).sub("...", "\\.\\.\\.")
           end
@@ -76,18 +76,7 @@ module Gitlab
           attachments = format_attachments(raw_issue["id"], 0, issue_comment["attachments"])
 
           body = format_issue_body(author, date, content, attachments)
-
-          labels = []
-          raw_issue["labels"].each do |label|
-            name = nice_label_name(label)
-            labels << name
-
-            unless @known_labels.include?(name)
-              create_label(name)
-              @known_labels << name
-            end
-          end
-          labels << nice_status_name(raw_issue["status"])
+          labels = import_issue_labels(raw_issue)
 
           assignee_id = nil
           if raw_issue.has_key?("owner")
@@ -110,6 +99,7 @@ module Gitlab
             assignee_id:  assignee_id,
             state:        raw_issue["state"] == "closed" ? "closed" : "opened"
           )
+
           issue.add_labels_by_names(labels)
 
           if issue.iid != raw_issue["id"]
@@ -120,6 +110,23 @@ module Gitlab
         end
       end
 
+      def import_issue_labels(raw_issue)
+        labels = []
+
+        raw_issue["labels"].each do |label|
+          name = nice_label_name(label)
+          labels << name
+
+          unless @known_labels.include?(name)
+            create_label(name)
+            @known_labels << name
+          end
+        end
+
+        labels << nice_status_name(raw_issue["status"])
+        labels
+      end
+
       def import_issue_comments(issue, comments)
         Note.transaction do
           while raw_comment = comments.shift
@@ -164,15 +171,13 @@ module Gitlab
         when /\AMilestone:/
           "#fee3ff"
 
-        when *@closed_statuses.map { |s| nice_status_name(s) }
-          "#cfcfcf"
         when "Status: New"
           "#428bca"
         when "Status: Accepted"
           "#5cb85c"
         when "Status: Started"
           "#8e44ad"
-        
+
         when "Priority: Critical"
           "#ffcfcf"
         when "Priority: High"
@@ -181,7 +186,7 @@ module Gitlab
           "#fff5cc"
         when "Priority: Low"
           "#cfe9ff"
-        
+
         when "Type: Defect"
           "#d9534f"
         when "Type: Enhancement"
@@ -192,6 +197,8 @@ module Gitlab
           "#8e44ad"
         when "Type: Other"
           "#7f8c8d"
+        when *@closed_statuses.map { |s| nice_status_name(s) }
+          "#cfcfcf"
         else
           "#e2e2e2"
         end
@@ -220,7 +227,7 @@ module Gitlab
         s = s.gsub("`", "\\`")
 
         # Carriage returns make me sad
-        s = s.gsub("\r", "")
+        s = s.delete("\r")
 
         # Markdown ignores single newlines, but we need them as <br />.
         s = s.gsub("\n", "  \n")
@@ -249,8 +256,8 @@ module Gitlab
         end
 
         if raw_updates.has_key?("cc")
-          cc = raw_updates["cc"].map do |l| 
-            deleted = l.start_with?("-") 
+          cc = raw_updates["cc"].map do |l|
+            deleted = l.start_with?("-")
             l = l[1..-1] if deleted
             l = user_map[l]
             l = "~~#{l}~~" if deleted
@@ -261,8 +268,8 @@ module Gitlab
         end
 
         if raw_updates.has_key?("labels")
-          labels = raw_updates["labels"].map do |l| 
-            deleted = l.start_with?("-") 
+          labels = raw_updates["labels"].map do |l|
+            deleted = l.start_with?("-")
             l = l[1..-1] if deleted
             l = nice_label_name(l)
             l = "~~#{l}~~" if deleted
@@ -278,45 +285,39 @@ module Gitlab
 
         if raw_updates.has_key?("blockedOn")
           blocked_ons = raw_updates["blockedOn"].map do |raw_blocked_on|
-            name, id = raw_blocked_on.split(":", 2)
-
-            deleted = name.start_with?("-") 
-            name = name[1..-1] if deleted
-
-            text =
-              if name == project.import_source
-                "##{id}"
-              else
-                "#{project.namespace.path}/#{name}##{id}"
-              end
-            text = "~~#{text}~~" if deleted
-            text
+            format_blocking_updates(raw_blocked_on)
           end
+
           updates << "*Blocked on: #{blocked_ons.join(", ")}*"
         end
 
         if raw_updates.has_key?("blocking")
           blockings = raw_updates["blocking"].map do |raw_blocked_on|
-            name, id = raw_blocked_on.split(":", 2)
-            
-            deleted = name.start_with?("-") 
-            name = name[1..-1] if deleted
-
-            text =
-              if name == project.import_source
-                "##{id}"
-              else
-                "#{project.namespace.path}/#{name}##{id}"
-              end
-            text = "~~#{text}~~" if deleted
-            text
+            format_blocking_updates(raw_blocked_on)
           end
+
           updates << "*Blocking: #{blockings.join(", ")}*"
         end
 
         updates
       end
 
+      def format_blocking_updates(raw_blocked_on)
+        name, id = raw_blocked_on.split(":", 2)
+
+        deleted = name.start_with?("-")
+        name = name[1..-1] if deleted
+
+        text =
+          if name == project.import_source
+            "##{id}"
+          else
+            "#{project.namespace.path}/#{name}##{id}"
+          end
+        text = "~~#{text}~~" if deleted
+        text
+      end
+
       def format_attachments(issue_id, comment_id, raw_attachments)
         return [] unless raw_attachments
 
@@ -325,7 +326,7 @@ module Gitlab
 
           filename = attachment["fileName"]
           link = "https://storage.googleapis.com/google-code-attachments/#{@repo.name}/issue-#{issue_id}/comment-#{comment_id}/#{filename}"
-          
+
           text = "[#{filename}](#{link})"
           text = "!#{text}" if filename =~ /\.(png|jpg|jpeg|gif|bmp|tiff)\z/i
           text
diff --git a/lib/gitlab/google_code_import/project_creator.rb b/lib/gitlab/google_code_import/project_creator.rb
index 1cb7d16aeb3..87821c23460 100644
--- a/lib/gitlab/google_code_import/project_creator.rb
+++ b/lib/gitlab/google_code_import/project_creator.rb
@@ -11,7 +11,8 @@ module Gitlab
       end
 
       def execute
-        project = ::Projects::CreateService.new(current_user,
+        project = ::Projects::CreateService.new(
+          current_user,
           name: repo.name,
           path: repo.name,
           description: repo.summary,
diff --git a/lib/gitlab/inline_diff.rb b/lib/gitlab/inline_diff.rb
index 99e7b529ba9..44507bde25d 100644
--- a/lib/gitlab/inline_diff.rb
+++ b/lib/gitlab/inline_diff.rb
@@ -11,48 +11,71 @@ module Gitlab
         indexes.each do |index|
           first_line = diff_arr[index+1]
           second_line = diff_arr[index+2]
-          max_length = [first_line.size, second_line.size].max
 
           # Skip inline diff if empty line was replaced with content
           next if first_line == "-\n"
 
-          first_the_same_symbols = 0
-          (0..max_length + 1).each do |i|
-            first_the_same_symbols = i - 1
-            if first_line[i] != second_line[i] && i > 0
-              break
-            end
-          end
+          first_token = find_first_token(first_line, second_line)
+          apply_first_token(diff_arr, index, first_token)
+
+          last_token = find_last_token(first_line, second_line, first_token)
+          apply_last_token(diff_arr, index, last_token)
+        end
+
+        diff_arr
+      end
+
+      def apply_first_token(diff_arr, index, first_token)
+        start = first_token + START
+
+        if first_token.empty?
+          # In case if we remove string of spaces in commit
+          diff_arr[index+1].sub!("-", "-" => "-#{START}")
+          diff_arr[index+2].sub!("+", "+" => "+#{START}")
+        else
+          diff_arr[index+1].sub!(first_token, first_token => start)
+          diff_arr[index+2].sub!(first_token, first_token => start)
+        end
+      end
 
-          first_token = first_line[0..first_the_same_symbols][1..-1]
-          start = first_token + START
+      def apply_last_token(diff_arr, index, last_token)
+        # This is tricky: escape backslashes so that `sub` doesn't interpret them
+        # as backreferences. Regexp.escape does NOT do the right thing.
+        replace_token = FINISH + last_token.gsub(/\\/, '\&\&')
+        diff_arr[index+1].sub!(/#{Regexp.escape(last_token)}$/, replace_token)
+        diff_arr[index+2].sub!(/#{Regexp.escape(last_token)}$/, replace_token)
+      end
+
+      def find_first_token(first_line, second_line)
+        max_length = [first_line.size, second_line.size].max
+        first_the_same_symbols = 0
+
+        (0..max_length + 1).each do |i|
+          first_the_same_symbols = i - 1
 
-          if first_token.empty?
-            # In case if we remove string of spaces in commit
-            diff_arr[index+1].sub!("-", "-" => "-#{START}")
-            diff_arr[index+2].sub!("+", "+" => "+#{START}")
-          else
-            diff_arr[index+1].sub!(first_token, first_token => start)
-            diff_arr[index+2].sub!(first_token, first_token => start)
+          if first_line[i] != second_line[i] && i > 0
+            break
           end
+        end
+
+        first_line[0..first_the_same_symbols][1..-1]
+      end
+
+      def find_last_token(first_line, second_line, first_token)
+        max_length = [first_line.size, second_line.size].max
+        last_the_same_symbols = 0
+
+        (1..max_length + 1).each do |i|
+          last_the_same_symbols = -i
+          shortest_line = second_line.size > first_line.size ? first_line : second_line
 
-          last_the_same_symbols = 0
-          (1..max_length + 1).each do |i|
-            last_the_same_symbols = -i
-            shortest_line = second_line.size > first_line.size ? first_line : second_line
-            if ( first_line[-i] != second_line[-i] ) || "#{first_token}#{START}".size == shortest_line[1..-i].size
-              break
-            end
+          if (first_line[-i] != second_line[-i]) || "#{first_token}#{START}".size == shortest_line[1..-i].size
+            break
           end
-          last_the_same_symbols += 1
-          last_token = first_line[last_the_same_symbols..-1]
-          # This is tricky: escape backslashes so that `sub` doesn't interpret them
-          # as backreferences. Regexp.escape does NOT do the right thing.
-          replace_token = FINISH + last_token.gsub(/\\/, '\&\&')
-          diff_arr[index+1].sub!(/#{Regexp.escape(last_token)}$/, replace_token)
-          diff_arr[index+2].sub!(/#{Regexp.escape(last_token)}$/, replace_token)
         end
-        diff_arr
+
+        last_the_same_symbols += 1
+        first_line[last_the_same_symbols..-1]
       end
 
       def _indexes_of_changed_lines(diff_arr)
diff --git a/lib/gitlab/ldap/access.rb b/lib/gitlab/ldap/access.rb
index 16ff03c38d4..c438a3d167b 100644
--- a/lib/gitlab/ldap/access.rb
+++ b/lib/gitlab/ldap/access.rb
@@ -37,13 +37,15 @@ module Gitlab
 
           # Block user in GitLab if he/she was blocked in AD
           if Gitlab::LDAP::Person.disabled_via_active_directory?(user.ldap_identity.extern_uid, adapter)
-            user.block unless user.blocked?
+            user.block
             false
           else
             user.activate if user.blocked? && !ldap_config.block_auto_created_users
             true
           end
         else
+          # Block the user if they no longer exist in LDAP/AD
+          user.block 
           false
         end
       rescue
diff --git a/lib/gitlab/ldap/user.rb b/lib/gitlab/ldap/user.rb
index 4be99dd88c2..aef08c97d1d 100644
--- a/lib/gitlab/ldap/user.rb
+++ b/lib/gitlab/ldap/user.rb
@@ -14,7 +14,7 @@ module Gitlab
           # LDAP distinguished name is case-insensitive
           identity = ::Identity.
             where(provider: provider).
-            where('lower(extern_uid) = ?', uid.mb_chars.downcase.to_s).last
+            iwhere(extern_uid: uid).last
           identity && identity.user
         end
       end
@@ -31,7 +31,7 @@ module Gitlab
 
       def find_by_uid_and_provider
         self.class.find_by_uid_and_provider(
-          auth_hash.uid.downcase, auth_hash.provider)
+          auth_hash.uid, auth_hash.provider)
       end
 
       def find_by_email
@@ -47,7 +47,7 @@ module Gitlab
         # find_or_initialize_by doesn't update `gl_user.identities`, and isn't autosaved.
         identity = gl_user.identities.find { |identity|  identity.provider == auth_hash.provider }
         identity ||= gl_user.identities.build(provider: auth_hash.provider)
-        
+
         # For a new user set extern_uid to the LDAP DN
         # For an existing user with matching email but changed DN, update the DN.
         # For an existing user with no change in DN, this line changes nothing.
diff --git a/lib/gitlab/lfs/response.rb b/lib/gitlab/lfs/response.rb
new file mode 100644
index 00000000000..9d9617761b3
--- /dev/null
+++ b/lib/gitlab/lfs/response.rb
@@ -0,0 +1,327 @@
+module Gitlab
+  module Lfs
+    class Response
+
+      def initialize(project, user, request)
+        @origin_project = project
+        @project = storage_project(project)
+        @user = user
+        @env = request.env
+        @request = request
+      end
+
+      def render_download_object_response(oid)
+        render_response_to_download do
+          if check_download_sendfile_header?
+            render_lfs_sendfile(oid)
+          else
+            render_not_found
+          end
+        end
+      end
+
+      def render_batch_operation_response
+        request_body = JSON.parse(@request.body.read)
+        case request_body["operation"]
+        when "download"
+          render_batch_download(request_body)
+        when "upload"
+          render_batch_upload(request_body)
+        else
+          render_not_found
+        end
+      end
+
+      def render_storage_upload_authorize_response(oid, size)
+        render_response_to_push do
+          [
+            200,
+            { "Content-Type" => "application/json; charset=utf-8" },
+            [JSON.dump({
+              'StoreLFSPath' => "#{Gitlab.config.lfs.storage_path}/tmp/upload",
+              'LfsOid' => oid,
+              'LfsSize' => size
+            })]
+          ]
+        end
+      end
+
+      def render_storage_upload_store_response(oid, size, tmp_file_name)
+        render_response_to_push do
+          render_lfs_upload_ok(oid, size, tmp_file_name)
+        end
+      end
+
+      def render_unsupported_deprecated_api
+        [
+          501,
+          { "Content-Type" => "application/json; charset=utf-8" },
+          [JSON.dump({
+            'message' => 'Server supports batch API only, please update your Git LFS client to version 1.0.1 and up.',
+            'documentation_url' => "#{Gitlab.config.gitlab.url}/help",
+          })]
+        ]
+      end
+
+      private
+
+      def render_not_enabled
+        [
+          501,
+          {
+            "Content-Type" => "application/json; charset=utf-8",
+          },
+          [JSON.dump({
+            'message' => 'Git LFS is not enabled on this GitLab server, contact your admin.',
+            'documentation_url' => "#{Gitlab.config.gitlab.url}/help",
+          })]
+        ]
+      end
+
+      def render_unauthorized
+        [
+          401,
+          {
+            'Content-Type' => 'text/plain'
+          },
+          ['Unauthorized']
+        ]
+      end
+
+      def render_not_found
+        [
+          404,
+          {
+            "Content-Type" => "application/vnd.git-lfs+json"
+          },
+          [JSON.dump({
+            'message' => 'Not found.',
+            'documentation_url' => "#{Gitlab.config.gitlab.url}/help",
+          })]
+        ]
+      end
+
+      def render_forbidden
+        [
+          403,
+          {
+            "Content-Type" => "application/vnd.git-lfs+json"
+          },
+          [JSON.dump({
+            'message' => 'Access forbidden. Check your access level.',
+            'documentation_url' => "#{Gitlab.config.gitlab.url}/help",
+          })]
+        ]
+      end
+
+      def render_lfs_sendfile(oid)
+        return render_not_found unless oid.present?
+
+        lfs_object = object_for_download(oid)
+
+        if lfs_object && lfs_object.file.exists?
+          [
+            200,
+            {
+              # GitLab-workhorse will forward Content-Type header
+              "Content-Type" => "application/octet-stream",
+              "X-Sendfile" => lfs_object.file.path
+            },
+            []
+          ]
+        else
+          render_not_found
+        end
+      end
+
+      def render_batch_upload(body)
+        return render_not_found if body.empty? || body['objects'].nil?
+
+        render_response_to_push do
+          response = build_upload_batch_response(body['objects'])
+          [
+            200,
+            {
+              "Content-Type" => "application/json; charset=utf-8",
+              "Cache-Control" => "private",
+            },
+            [JSON.dump(response)]
+          ]
+        end
+      end
+
+      def render_batch_download(body)
+        return render_not_found if body.empty? || body['objects'].nil?
+
+        render_response_to_download do
+          response = build_download_batch_response(body['objects'])
+          [
+            200,
+            {
+              "Content-Type" => "application/json; charset=utf-8",
+              "Cache-Control" => "private",
+            },
+            [JSON.dump(response)]
+          ]
+        end
+      end
+
+      def render_lfs_upload_ok(oid, size, tmp_file)
+        if store_file(oid, size, tmp_file)
+          [
+            200,
+            {
+              'Content-Type' => 'text/plain',
+              'Content-Length' => 0
+            },
+            []
+          ]
+        else
+          [
+            422,
+            { 'Content-Type' => 'text/plain' },
+            ["Unprocessable entity"]
+          ]
+        end
+      end
+
+      def render_response_to_download
+        return render_not_enabled unless Gitlab.config.lfs.enabled
+
+        unless @project.public?
+          return render_unauthorized unless @user
+          return render_forbidden unless user_can_fetch?
+        end
+
+        yield
+      end
+
+      def render_response_to_push
+        return render_not_enabled unless Gitlab.config.lfs.enabled
+        return render_unauthorized unless @user
+        return render_forbidden unless user_can_push?
+
+        yield
+      end
+
+      def check_download_sendfile_header?
+        @env['HTTP_X_SENDFILE_TYPE'].to_s == "X-Sendfile"
+      end
+
+      def user_can_fetch?
+        # Check user access against the project they used to initiate the pull
+        @user.can?(:download_code, @origin_project)
+      end
+
+      def user_can_push?
+        # Check user access against the project they used to initiate the push
+        @user.can?(:push_code, @origin_project)
+      end
+
+      def storage_project(project)
+        if project.forked?
+          storage_project(project.forked_from_project)
+        else
+          project
+        end
+      end
+
+      def store_file(oid, size, tmp_file)
+        tmp_file_path = File.join("#{Gitlab.config.lfs.storage_path}/tmp/upload", tmp_file)
+
+        object = LfsObject.find_or_create_by(oid: oid, size: size)
+        if object.file.exists?
+          success = true
+        else
+          success = move_tmp_file_to_storage(object, tmp_file_path)
+        end
+
+        if success
+          success = link_to_project(object)
+        end
+
+        success
+      ensure
+        # Ensure that the tmp file is removed
+        FileUtils.rm_f(tmp_file_path)
+      end
+
+      def object_for_download(oid)
+        @project.lfs_objects.find_by(oid: oid)
+      end
+
+      def move_tmp_file_to_storage(object, path)
+        File.open(path) do |f|
+          object.file = f
+        end
+
+        object.file.store!
+        object.save
+      end
+
+      def link_to_project(object)
+        if object && !object.projects.exists?(@project.id)
+          object.projects << @project
+          object.save
+        end
+      end
+
+      def select_existing_objects(objects)
+        objects_oids = objects.map { |o| o['oid'] }
+        @project.lfs_objects.where(oid: objects_oids).pluck(:oid).to_set
+      end
+
+      def build_upload_batch_response(objects)
+        selected_objects = select_existing_objects(objects)
+
+        upload_hypermedia_links(objects, selected_objects)
+      end
+
+      def build_download_batch_response(objects)
+        selected_objects = select_existing_objects(objects)
+
+        download_hypermedia_links(objects, selected_objects)
+      end
+
+      def download_hypermedia_links(all_objects, existing_objects)
+        all_objects.each do |object|
+          if existing_objects.include?(object['oid'])
+            object['actions'] = {
+              'download' => {
+                'href' => "#{@origin_project.http_url_to_repo}/gitlab-lfs/objects/#{object['oid']}",
+                'header' => {
+                  'Authorization' => @env['HTTP_AUTHORIZATION']
+                }.compact
+              }
+            }
+          else
+            object['error'] = {
+              'code' => 404,
+              'message' => "Object does not exist on the server or you don't have permissions to access it",
+            }
+          end
+        end
+
+        { 'objects' => all_objects }
+      end
+
+      def upload_hypermedia_links(all_objects, existing_objects)
+        all_objects.each do |object|
+          # generate actions only for non-existing objects
+          next if existing_objects.include?(object['oid'])
+
+          object['actions'] = {
+            'upload' => {
+              'href' => "#{@origin_project.http_url_to_repo}/gitlab-lfs/objects/#{object['oid']}/#{object['size']}",
+              'header' => {
+                'Authorization' => @env['HTTP_AUTHORIZATION']
+              }.compact
+            }
+          }
+        end
+
+        { 'objects' => all_objects }
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/lfs/router.rb b/lib/gitlab/lfs/router.rb
new file mode 100644
index 00000000000..78d02891102
--- /dev/null
+++ b/lib/gitlab/lfs/router.rb
@@ -0,0 +1,97 @@
+module Gitlab
+  module Lfs
+    class Router
+      def initialize(project, user, request)
+        @project = project
+        @user = user
+        @env = request.env
+        @request = request
+      end
+
+      def try_call
+        return unless @request && @request.path.present?
+
+        case @request.request_method
+        when 'GET'
+          get_response
+        when 'POST'
+          post_response
+        when 'PUT'
+          put_response
+        else
+          nil
+        end
+      end
+
+      private
+
+      def get_response
+        path_match = @request.path.match(/\/(info\/lfs|gitlab-lfs)\/objects\/([0-9a-f]{64})$/)
+        return nil unless path_match
+
+        oid = path_match[2]
+        return nil unless oid
+
+        case path_match[1]
+        when "info/lfs"
+          lfs.render_unsupported_deprecated_api
+        when "gitlab-lfs"
+          lfs.render_download_object_response(oid)
+        else
+          nil
+        end
+      end
+
+      def post_response
+        post_path = @request.path.match(/\/info\/lfs\/objects(\/batch)?$/)
+        return nil unless post_path
+
+        # Check for Batch API
+        if post_path[0].ends_with?("/info/lfs/objects/batch")
+          lfs.render_batch_operation_response
+        elsif post_path[0].ends_with?("/info/lfs/objects")
+          lfs.render_unsupported_deprecated_api
+        else
+          nil
+        end
+      end
+
+      def put_response
+        object_match = @request.path.match(/\/gitlab-lfs\/objects\/([0-9a-f]{64})\/([0-9]+)(|\/authorize){1}$/)
+        return nil if object_match.nil?
+
+        oid = object_match[1]
+        size = object_match[2].try(:to_i)
+        return nil if oid.nil? || size.nil?
+
+        # GitLab-workhorse requests
+        # 1. Try to authorize the request
+        # 2. send a request with a header containing the name of the temporary file
+        if object_match[3] && object_match[3] == '/authorize'
+          lfs.render_storage_upload_authorize_response(oid, size)
+        else
+          tmp_file_name = sanitize_tmp_filename(@request.env['HTTP_X_GITLAB_LFS_TMP'])
+          return nil unless tmp_file_name
+
+          lfs.render_storage_upload_store_response(oid, size, tmp_file_name)
+        end
+      end
+
+      def lfs
+        return unless @project
+
+        Gitlab::Lfs::Response.new(@project, @user, @request)
+      end
+
+      def sanitize_tmp_filename(name)
+        if name.present?
+          name.gsub!(/^.*(\\|\/)/, '')
+          name = name.match(/[0-9a-f]{73}/)
+          name[0] if name
+        else
+          nil
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/markdown.rb b/lib/gitlab/markdown.rb
deleted file mode 100644
index b082bfc434b..00000000000
--- a/lib/gitlab/markdown.rb
+++ /dev/null
@@ -1,200 +0,0 @@
-require 'html/pipeline'
-
-module Gitlab
-  # Custom parser for GitLab-flavored Markdown
-  #
-  # See the files in `lib/gitlab/markdown/` for specific processing information.
-  module Markdown
-    # Convert a Markdown String into an HTML-safe String of HTML
-    #
-    # Note that while the returned HTML will have been sanitized of dangerous
-    # HTML, it may post a risk of information leakage if it's not also passed
-    # through `post_process`.
-    #
-    # Also note that the returned String is always HTML, not XHTML. Views
-    # requiring XHTML, such as Atom feeds, need to call `post_process` on the
-    # result, providing the appropriate `pipeline` option.
-    #
-    # markdown - Markdown String
-    # context  - Hash of context options passed to our HTML Pipeline
-    #
-    # Returns an HTML-safe String
-    def self.render(markdown, context = {})
-      html = renderer.render(markdown)
-      html = gfm(html, context)
-
-      html.html_safe
-    end
-
-    # Convert a Markdown String into HTML without going through the HTML
-    # Pipeline.
-    #
-    # Note that because the pipeline is skipped, SanitizationFilter is as well.
-    # Do not output the result of this method to the user.
-    #
-    # markdown - Markdown String
-    #
-    # Returns a String
-    def self.render_without_gfm(markdown)
-      renderer.render(markdown)
-    end
-
-    # Perform post-processing on an HTML String
-    #
-    # This method is used to perform state-dependent changes to a String of
-    # HTML, such as removing references that the current user doesn't have
-    # permission to make (`RedactorFilter`).
-    #
-    # html     - String to process
-    # options  - Hash of options to customize output
-    #            :pipeline  - Symbol pipeline type
-    #            :project   - Project
-    #            :user      - User object
-    #
-    # Returns an HTML-safe String
-    def self.post_process(html, options)
-      context = {
-        project:      options[:project],
-        current_user: options[:user]
-      }
-      doc = post_processor.to_document(html, context)
-
-      if options[:pipeline] == :atom
-        doc.to_html(save_with: Nokogiri::XML::Node::SaveOptions::AS_XHTML)
-      else
-        doc.to_html
-      end.html_safe
-    end
-
-    # Provide autoload paths for filters to prevent a circular dependency error
-    autoload :AutolinkFilter,               'gitlab/markdown/autolink_filter'
-    autoload :CommitRangeReferenceFilter,   'gitlab/markdown/commit_range_reference_filter'
-    autoload :CommitReferenceFilter,        'gitlab/markdown/commit_reference_filter'
-    autoload :EmojiFilter,                  'gitlab/markdown/emoji_filter'
-    autoload :ExternalIssueReferenceFilter, 'gitlab/markdown/external_issue_reference_filter'
-    autoload :ExternalLinkFilter,           'gitlab/markdown/external_link_filter'
-    autoload :IssueReferenceFilter,         'gitlab/markdown/issue_reference_filter'
-    autoload :LabelReferenceFilter,         'gitlab/markdown/label_reference_filter'
-    autoload :MergeRequestReferenceFilter,  'gitlab/markdown/merge_request_reference_filter'
-    autoload :RedactorFilter,               'gitlab/markdown/redactor_filter'
-    autoload :RelativeLinkFilter,           'gitlab/markdown/relative_link_filter'
-    autoload :SanitizationFilter,           'gitlab/markdown/sanitization_filter'
-    autoload :SnippetReferenceFilter,       'gitlab/markdown/snippet_reference_filter'
-    autoload :SyntaxHighlightFilter,        'gitlab/markdown/syntax_highlight_filter'
-    autoload :TableOfContentsFilter,        'gitlab/markdown/table_of_contents_filter'
-    autoload :TaskListFilter,               'gitlab/markdown/task_list_filter'
-    autoload :UserReferenceFilter,          'gitlab/markdown/user_reference_filter'
-    autoload :UploadLinkFilter,             'gitlab/markdown/upload_link_filter'
-
-    # Public: Parse the provided HTML with GitLab-Flavored Markdown
-    #
-    # html    - HTML String
-    # options - A Hash of options used to customize output (default: {})
-    #           :no_header_anchors - Disable header anchors in TableOfContentsFilter
-    #           :path              - Current path String
-    #           :pipeline          - Symbol pipeline type
-    #           :project           - Current Project object
-    #           :project_wiki      - Current ProjectWiki object
-    #           :ref               - Current ref String
-    #
-    # Returns an HTML-safe String
-    def self.gfm(html, options = {})
-      return '' unless html.present?
-
-      @pipeline ||= HTML::Pipeline.new(filters)
-
-      context = {
-        # SanitizationFilter
-        pipeline: options[:pipeline],
-
-        # EmojiFilter
-        asset_host: Gitlab::Application.config.asset_host,
-        asset_root: Gitlab.config.gitlab.base_url,
-
-        # ReferenceFilter
-        only_path: only_path_pipeline?(options[:pipeline]),
-        project:   options[:project],
-
-        # RelativeLinkFilter
-        project_wiki:   options[:project_wiki],
-        ref:            options[:ref],
-        requested_path: options[:path],
-
-        # TableOfContentsFilter
-        no_header_anchors: options[:no_header_anchors]
-      }
-
-      @pipeline.to_html(html, context).html_safe
-    end
-
-    private
-
-    # Check if a pipeline enables the `only_path` context option
-    #
-    # Returns Boolean
-    def self.only_path_pipeline?(pipeline)
-      case pipeline
-      when :atom, :email
-        false
-      else
-        true
-      end
-    end
-
-    def self.redcarpet_options
-      # https://github.com/vmg/redcarpet#and-its-like-really-simple-to-use
-      @redcarpet_options ||= {
-        fenced_code_blocks:  true,
-        footnotes:           true,
-        lax_spacing:         true,
-        no_intra_emphasis:   true,
-        space_after_headers: true,
-        strikethrough:       true,
-        superscript:         true,
-        tables:              true
-      }.freeze
-    end
-
-    def self.renderer
-      @markdown ||= begin
-        renderer = Redcarpet::Render::HTML.new
-        Redcarpet::Markdown.new(renderer, redcarpet_options)
-      end
-    end
-
-    def self.post_processor
-      @post_processor ||= HTML::Pipeline.new([Gitlab::Markdown::RedactorFilter])
-    end
-
-    # Filters used in our pipeline
-    #
-    # SanitizationFilter should come first so that all generated reference HTML
-    # goes through untouched.
-    #
-    # See https://github.com/jch/html-pipeline#filters for more filters.
-    def self.filters
-      [
-        Gitlab::Markdown::SyntaxHighlightFilter,
-        Gitlab::Markdown::SanitizationFilter,
-
-        Gitlab::Markdown::UploadLinkFilter,
-        Gitlab::Markdown::RelativeLinkFilter,
-        Gitlab::Markdown::EmojiFilter,
-        Gitlab::Markdown::TableOfContentsFilter,
-        Gitlab::Markdown::AutolinkFilter,
-        Gitlab::Markdown::ExternalLinkFilter,
-
-        Gitlab::Markdown::UserReferenceFilter,
-        Gitlab::Markdown::IssueReferenceFilter,
-        Gitlab::Markdown::ExternalIssueReferenceFilter,
-        Gitlab::Markdown::MergeRequestReferenceFilter,
-        Gitlab::Markdown::SnippetReferenceFilter,
-        Gitlab::Markdown::CommitRangeReferenceFilter,
-        Gitlab::Markdown::CommitReferenceFilter,
-        Gitlab::Markdown::LabelReferenceFilter,
-
-        Gitlab::Markdown::TaskListFilter
-      ]
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/autolink_filter.rb b/lib/gitlab/markdown/autolink_filter.rb
deleted file mode 100644
index c37c3bc55bf..00000000000
--- a/lib/gitlab/markdown/autolink_filter.rb
+++ /dev/null
@@ -1,107 +0,0 @@
-require 'gitlab/markdown'
-require 'html/pipeline/filter'
-require 'uri'
-
-module Gitlab
-  module Markdown
-    # HTML Filter for auto-linking URLs in HTML.
-    #
-    # Based on HTML::Pipeline::AutolinkFilter
-    #
-    # Context options:
-    #   :autolink  - Boolean, skips all processing done by this filter when false
-    #   :link_attr - Hash of attributes for the generated links
-    #
-    class AutolinkFilter < HTML::Pipeline::Filter
-      include ActionView::Helpers::TagHelper
-
-      # Pattern to match text that should be autolinked.
-      #
-      # A URI scheme begins with a letter and may contain letters, numbers,
-      # plus, period and hyphen. Schemes are case-insensitive but we're being
-      # picky here and allowing only lowercase for autolinks.
-      #
-      # See http://en.wikipedia.org/wiki/URI_scheme
-      #
-      # The negative lookbehind ensures that users can paste a URL followed by a
-      # period or comma for punctuation without those characters being included
-      # in the generated link.
-      #
-      # Rubular: http://rubular.com/r/cxjPyZc7Sb
-      LINK_PATTERN = %r{([a-z][a-z0-9\+\.-]+://\S+)(?<!,|\.)}
-
-      # Text matching LINK_PATTERN inside these elements will not be linked
-      IGNORE_PARENTS = %w(a code kbd pre script style).to_set
-
-      def call
-        return doc if context[:autolink] == false
-
-        rinku_parse
-        text_parse
-      end
-
-      private
-
-      # Run the text through Rinku as a first pass
-      #
-      # This will quickly autolink http(s) and ftp links.
-      #
-      # `@doc` will be re-parsed with the HTML String from Rinku.
-      def rinku_parse
-        # Convert the options from a Hash to a String that Rinku expects
-        options = tag_options(link_options)
-
-        # NOTE: We don't parse email links because it will erroneously match
-        # external Commit and CommitRange references.
-        #
-        # The final argument tells Rinku to link short URLs that don't include a
-        # period (e.g., http://localhost:3000/)
-        rinku = Rinku.auto_link(html, :urls, options, IGNORE_PARENTS.to_a, 1)
-
-        # Rinku returns a String, so parse it back to a Nokogiri::XML::Document
-        # for further processing.
-        @doc = parse_html(rinku)
-      end
-
-      # Autolinks any text matching LINK_PATTERN that Rinku didn't already
-      # replace
-      def text_parse
-        search_text_nodes(doc).each do |node|
-          content = node.to_html
-
-          next if has_ancestor?(node, IGNORE_PARENTS)
-          next unless content.match(LINK_PATTERN)
-
-          # If Rinku didn't link this, there's probably a good reason, so we'll
-          # skip it too
-          next if content.start_with?(*%w(http https ftp))
-
-          html = autolink_filter(content)
-
-          next if html == content
-
-          node.replace(html)
-        end
-
-        doc
-      end
-
-      def autolink_filter(text)
-        text.gsub(LINK_PATTERN) do |match|
-          # Remove any trailing HTML entities and store them for appending
-          # outside the link element. The entity must be marked HTML safe in
-          # order to be output literally rather than escaped.
-          match.gsub!(/((?:&[\w#]+;)+)\z/, '')
-          dropped = ($1 || '').html_safe
-
-          options = link_options.merge(href: match)
-          content_tag(:a, match, options) + dropped
-        end
-      end
-
-      def link_options
-        @link_options ||= context[:link_attr] || {}
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/commit_range_reference_filter.rb b/lib/gitlab/markdown/commit_range_reference_filter.rb
deleted file mode 100644
index e070edae0a4..00000000000
--- a/lib/gitlab/markdown/commit_range_reference_filter.rb
+++ /dev/null
@@ -1,92 +0,0 @@
-require 'gitlab/markdown'
-
-module Gitlab
-  module Markdown
-    # HTML filter that replaces commit range references with links.
-    #
-    # This filter supports cross-project references.
-    class CommitRangeReferenceFilter < ReferenceFilter
-      include CrossProjectReference
-
-      # Public: Find commit range references in text
-      #
-      #   CommitRangeReferenceFilter.references_in(text) do |match, commit_range, project_ref|
-      #     "<a href=...>#{commit_range}</a>"
-      #   end
-      #
-      # text - String text to search.
-      #
-      # Yields the String match, the String commit range, and an optional String
-      # of the external project reference.
-      #
-      # Returns a String replaced with the return of the block.
-      def self.references_in(text)
-        text.gsub(CommitRange.reference_pattern) do |match|
-          yield match, $~[:commit_range], $~[:project]
-        end
-      end
-
-      def self.referenced_by(node)
-        project = Project.find(node.attr("data-project")) rescue nil
-        return unless project
-
-        id = node.attr("data-commit-range")
-        range = CommitRange.new(id, project)
-
-        return unless range.valid_commits?
-
-        { commit_range: range }
-      end
-
-      def initialize(*args)
-        super
-
-        @commit_map = {}
-      end
-
-      def call
-        replace_text_nodes_matching(CommitRange.reference_pattern) do |content|
-          commit_range_link_filter(content)
-        end
-      end
-
-      # Replace commit range references in text with links to compare the commit
-      # ranges.
-      #
-      # text - String text to replace references in.
-      #
-      # Returns a String with commit range references replaced with links. All
-      # links have `gfm` and `gfm-commit_range` class names attached for
-      # styling.
-      def commit_range_link_filter(text)
-        self.class.references_in(text) do |match, id, project_ref|
-          project = self.project_from_ref(project_ref)
-
-          range = CommitRange.new(id, project)
-
-          if range.valid_commits?
-            url = url_for_commit_range(project, range)
-
-            title = range.reference_title
-            klass = reference_class(:commit_range)
-            data  = data_attribute(project: project.id, commit_range: id)
-
-            project_ref += '@' if project_ref
-
-            %(<a href="#{url}" #{data}
-                 title="#{title}"
-                 class="#{klass}">#{project_ref}#{range}</a>)
-          else
-            match
-          end
-        end
-      end
-
-      def url_for_commit_range(project, range)
-        h = Gitlab::Application.routes.url_helpers
-        h.namespace_project_compare_url(project.namespace, project,
-                                        range.to_param.merge(only_path: context[:only_path]))
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/commit_reference_filter.rb b/lib/gitlab/markdown/commit_reference_filter.rb
deleted file mode 100644
index 8cdbeb1f9cf..00000000000
--- a/lib/gitlab/markdown/commit_reference_filter.rb
+++ /dev/null
@@ -1,88 +0,0 @@
-require 'gitlab/markdown'
-
-module Gitlab
-  module Markdown
-    # HTML filter that replaces commit references with links.
-    #
-    # This filter supports cross-project references.
-    class CommitReferenceFilter < ReferenceFilter
-      include CrossProjectReference
-
-      # Public: Find commit references in text
-      #
-      #   CommitReferenceFilter.references_in(text) do |match, commit, project_ref|
-      #     "<a href=...>#{commit}</a>"
-      #   end
-      #
-      # text - String text to search.
-      #
-      # Yields the String match, the String commit identifier, and an optional
-      # String of the external project reference.
-      #
-      # Returns a String replaced with the return of the block.
-      def self.references_in(text)
-        text.gsub(Commit.reference_pattern) do |match|
-          yield match, $~[:commit], $~[:project]
-        end
-      end
-
-      def self.referenced_by(node)
-        project = Project.find(node.attr("data-project")) rescue nil
-        return unless project
-
-        id = node.attr("data-commit")
-        commit = commit_from_ref(project, id)
-
-        return unless commit
-
-        { commit: commit }
-      end
-
-      def call
-        replace_text_nodes_matching(Commit.reference_pattern) do |content|
-          commit_link_filter(content)
-        end
-      end
-
-      # Replace commit references in text with links to the commit specified.
-      #
-      # text - String text to replace references in.
-      #
-      # Returns a String with commit references replaced with links. All links
-      # have `gfm` and `gfm-commit` class names attached for styling.
-      def commit_link_filter(text)
-        self.class.references_in(text) do |match, id, project_ref|
-          project = self.project_from_ref(project_ref)
-
-          if commit = self.class.commit_from_ref(project, id)
-            url = url_for_commit(project, commit)
-
-            title = escape_once(commit.link_title)
-            klass = reference_class(:commit)
-            data  = data_attribute(project: project.id, commit: id)
-
-            project_ref += '@' if project_ref
-
-            %(<a href="#{url}" #{data}
-                 title="#{title}"
-                 class="#{klass}">#{project_ref}#{commit.short_id}</a>)
-          else
-            match
-          end
-        end
-      end
-
-      def self.commit_from_ref(project, id)
-        if project && project.valid_repo?
-          project.commit(id)
-        end
-      end
-
-      def url_for_commit(project, commit)
-        h = Gitlab::Application.routes.url_helpers
-        h.namespace_project_commit_url(project.namespace, project, commit,
-                                        only_path: context[:only_path])
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/cross_project_reference.rb b/lib/gitlab/markdown/cross_project_reference.rb
deleted file mode 100644
index 6ab04a584b0..00000000000
--- a/lib/gitlab/markdown/cross_project_reference.rb
+++ /dev/null
@@ -1,24 +0,0 @@
-require 'gitlab/markdown'
-
-module Gitlab
-  module Markdown
-    # Common methods for ReferenceFilters that support an optional cross-project
-    # reference.
-    module CrossProjectReference
-      # Given a cross-project reference string, get the Project record
-      #
-      # Defaults to value of `context[:project]` if:
-      # * No reference is given OR
-      # * Reference given doesn't exist
-      #
-      # ref - String reference.
-      #
-      # Returns a Project, or nil if the reference can't be found
-      def project_from_ref(ref)
-        return context[:project] unless ref
-
-        Project.find_with_namespace(ref)
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/emoji_filter.rb b/lib/gitlab/markdown/emoji_filter.rb
deleted file mode 100644
index da10e4d3760..00000000000
--- a/lib/gitlab/markdown/emoji_filter.rb
+++ /dev/null
@@ -1,80 +0,0 @@
-require 'action_controller'
-require 'gitlab/markdown'
-require 'gitlab_emoji'
-require 'html/pipeline/filter'
-
-module Gitlab
-  module Markdown
-    # HTML filter that replaces :emoji: with images.
-    #
-    # Based on HTML::Pipeline::EmojiFilter
-    #
-    # Context options:
-    #   :asset_root
-    #   :asset_host
-    class EmojiFilter < HTML::Pipeline::Filter
-      IGNORED_ANCESTOR_TAGS = %w(pre code tt).to_set
-
-      def call
-        search_text_nodes(doc).each do |node|
-          content = node.to_html
-          next unless content.include?(':')
-          next if has_ancestor?(node, IGNORED_ANCESTOR_TAGS)
-
-          html = emoji_image_filter(content)
-
-          next if html == content
-
-          node.replace(html)
-        end
-
-        doc
-      end
-
-      # Replace :emoji: with corresponding images.
-      #
-      # text - String text to replace :emoji: in.
-      #
-      # Returns a String with :emoji: replaced with images.
-      def emoji_image_filter(text)
-        text.gsub(emoji_pattern) do |match|
-          name = $1
-          "<img class='emoji' title=':#{name}:' alt=':#{name}:' src='#{emoji_url(name)}' height='20' width='20' align='absmiddle' />"
-        end
-      end
-
-      private
-
-      def emoji_url(name)
-        emoji_path = "emoji/#{emoji_filename(name)}"
-        if context[:asset_host]
-          # Asset host is specified.
-          url_to_image(emoji_path)
-        elsif context[:asset_root]
-          # Gitlab url is specified
-          File.join(context[:asset_root], url_to_image(emoji_path))
-        else
-          # All other cases
-          url_to_image(emoji_path)
-        end
-      end
-
-      def url_to_image(image)
-        ActionController::Base.helpers.url_to_image(image)
-      end
-
-      # Build a regexp that matches all valid :emoji: names.
-      def self.emoji_pattern
-        @emoji_pattern ||= /:(#{Emoji.emojis_names.map { |name| Regexp.escape(name) }.join('|')}):/
-      end
-
-      def emoji_pattern
-        self.class.emoji_pattern
-      end
-
-      def emoji_filename(name)
-        "#{Emoji.emoji_filename(name)}.png"
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/external_issue_reference_filter.rb b/lib/gitlab/markdown/external_issue_reference_filter.rb
deleted file mode 100644
index 8f86f13976a..00000000000
--- a/lib/gitlab/markdown/external_issue_reference_filter.rb
+++ /dev/null
@@ -1,63 +0,0 @@
-require 'gitlab/markdown'
-
-module Gitlab
-  module Markdown
-    # HTML filter that replaces external issue tracker references with links.
-    # References are ignored if the project doesn't use an external issue
-    # tracker.
-    class ExternalIssueReferenceFilter < ReferenceFilter
-      # Public: Find `JIRA-123` issue references in text
-      #
-      #   ExternalIssueReferenceFilter.references_in(text) do |match, issue|
-      #     "<a href=...>##{issue}</a>"
-      #   end
-      #
-      # text - String text to search.
-      #
-      # Yields the String match and the String issue reference.
-      #
-      # Returns a String replaced with the return of the block.
-      def self.references_in(text)
-        text.gsub(ExternalIssue.reference_pattern) do |match|
-          yield match, $~[:issue]
-        end
-      end
-
-      def call
-        # Early return if the project isn't using an external tracker
-        return doc if project.nil? || project.default_issues_tracker?
-
-        replace_text_nodes_matching(ExternalIssue.reference_pattern) do |content|
-          issue_link_filter(content)
-        end
-      end
-
-      # Replace `JIRA-123` issue references in text with links to the referenced
-      # issue's details page.
-      #
-      # text - String text to replace references in.
-      #
-      # Returns a String with `JIRA-123` references replaced with links. All
-      # links have `gfm` and `gfm-issue` class names attached for styling.
-      def issue_link_filter(text)
-        project = context[:project]
-
-        self.class.references_in(text) do |match, issue|
-          url = url_for_issue(issue, project, only_path: context[:only_path])
-
-          title = escape_once("Issue in #{project.external_issue_tracker.title}")
-          klass = reference_class(:issue)
-          data  = data_attribute(project: project.id)
-
-          %(<a href="#{url}" #{data}
-               title="#{title}"
-               class="#{klass}">#{match}</a>)
-        end
-      end
-
-      def url_for_issue(*args)
-        IssuesHelper.url_for_issue(*args)
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/external_link_filter.rb b/lib/gitlab/markdown/external_link_filter.rb
deleted file mode 100644
index 29e51b6ade6..00000000000
--- a/lib/gitlab/markdown/external_link_filter.rb
+++ /dev/null
@@ -1,34 +0,0 @@
-require 'gitlab/markdown'
-require 'html/pipeline/filter'
-
-module Gitlab
-  module Markdown
-    # HTML Filter to add a `rel="nofollow"` attribute to external links
-    #
-    class ExternalLinkFilter < HTML::Pipeline::Filter
-      def call
-        doc.search('a').each do |node|
-          next unless node.has_attribute?('href')
-
-          link = node.attribute('href').value
-
-          # Skip non-HTTP(S) links
-          next unless link.start_with?('http')
-
-          # Skip internal links
-          next if link.start_with?(internal_url)
-
-          node.set_attribute('rel', 'nofollow')
-        end
-
-        doc
-      end
-
-      private
-
-      def internal_url
-        @internal_url ||= Gitlab.config.gitlab.url
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/issue_reference_filter.rb b/lib/gitlab/markdown/issue_reference_filter.rb
deleted file mode 100644
index 481d282f7b1..00000000000
--- a/lib/gitlab/markdown/issue_reference_filter.rb
+++ /dev/null
@@ -1,72 +0,0 @@
-require 'gitlab/markdown'
-
-module Gitlab
-  module Markdown
-    # HTML filter that replaces issue references with links. References to
-    # issues that do not exist are ignored.
-    #
-    # This filter supports cross-project references.
-    class IssueReferenceFilter < ReferenceFilter
-      include CrossProjectReference
-
-      # Public: Find `#123` issue references in text
-      #
-      #   IssueReferenceFilter.references_in(text) do |match, issue, project_ref|
-      #     "<a href=...>##{issue}</a>"
-      #   end
-      #
-      # text - String text to search.
-      #
-      # Yields the String match, the Integer issue ID, and an optional String of
-      # the external project reference.
-      #
-      # Returns a String replaced with the return of the block.
-      def self.references_in(text)
-        text.gsub(Issue.reference_pattern) do |match|
-          yield match, $~[:issue].to_i, $~[:project]
-        end
-      end
-
-      def self.referenced_by(node)
-        { issue: LazyReference.new(Issue, node.attr("data-issue")) }
-      end
-
-      def call
-        replace_text_nodes_matching(Issue.reference_pattern) do |content|
-          issue_link_filter(content)
-        end
-      end
-
-      # Replace `#123` issue references in text with links to the referenced
-      # issue's details page.
-      #
-      # text - String text to replace references in.
-      #
-      # Returns a String with `#123` references replaced with links. All links
-      # have `gfm` and `gfm-issue` class names attached for styling.
-      def issue_link_filter(text)
-        self.class.references_in(text) do |match, id, project_ref|
-          project = self.project_from_ref(project_ref)
-
-          if project && issue = project.get_issue(id)
-            url = url_for_issue(id, project, only_path: context[:only_path])
-
-            title = escape_once("Issue: #{issue.title}")
-            klass = reference_class(:issue)
-            data  = data_attribute(project: project.id, issue: issue.id)
-
-            %(<a href="#{url}" #{data}
-                 title="#{title}"
-                 class="#{klass}">#{match}</a>)
-          else
-            match
-          end
-        end
-      end
-
-      def url_for_issue(*args)
-        IssuesHelper.url_for_issue(*args)
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/label_reference_filter.rb b/lib/gitlab/markdown/label_reference_filter.rb
deleted file mode 100644
index 618acb7a578..00000000000
--- a/lib/gitlab/markdown/label_reference_filter.rb
+++ /dev/null
@@ -1,87 +0,0 @@
-require 'gitlab/markdown'
-
-module Gitlab
-  module Markdown
-    # HTML filter that replaces label references with links.
-    class LabelReferenceFilter < ReferenceFilter
-      # Public: Find label references in text
-      #
-      #   LabelReferenceFilter.references_in(text) do |match, id, name|
-      #     "<a href=...>#{Label.find(id)}</a>"
-      #   end
-      #
-      # text - String text to search.
-      #
-      # Yields the String match, an optional Integer label ID, and an optional
-      # String label name.
-      #
-      # Returns a String replaced with the return of the block.
-      def self.references_in(text)
-        text.gsub(Label.reference_pattern) do |match|
-          yield match, $~[:label_id].to_i, $~[:label_name]
-        end
-      end
-
-      def self.referenced_by(node)
-        { label: LazyReference.new(Label, node.attr("data-label")) }
-      end
-
-      def call
-        replace_text_nodes_matching(Label.reference_pattern) do |content|
-          label_link_filter(content)
-        end
-      end
-
-      # Replace label references in text with links to the label specified.
-      #
-      # text - String text to replace references in.
-      #
-      # Returns a String with label references replaced with links. All links
-      # have `gfm` and `gfm-label` class names attached for styling.
-      def label_link_filter(text)
-        project = context[:project]
-
-        self.class.references_in(text) do |match, id, name|
-          params = label_params(id, name)
-
-          if label = project.labels.find_by(params)
-            url = url_for_label(project, label)
-            klass = reference_class(:label)
-            data = data_attribute(project: project.id, label: label.id)
-
-            %(<a href="#{url}" #{data}
-                 class="#{klass}">#{render_colored_label(label)}</a>)
-          else
-            match
-          end
-        end
-      end
-
-      def url_for_label(project, label)
-        h = Gitlab::Application.routes.url_helpers
-        h.namespace_project_issues_path(project.namespace, project,
-                                        label_name: label.name,
-                                        only_path: context[:only_path])
-      end
-
-      def render_colored_label(label)
-        LabelsHelper.render_colored_label(label)
-      end
-
-      # Parameters to pass to `Label.find_by` based on the given arguments
-      #
-      # id   - Integer ID to pass. If present, returns {id: id}
-      # name - String name to pass. If `id` is absent, finds by name without
-      #        surrounding quotes.
-      #
-      # Returns a Hash.
-      def label_params(id, name)
-        if name
-          { name: name.tr('"', '') }
-        else
-          { id: id }
-        end
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/merge_request_reference_filter.rb b/lib/gitlab/markdown/merge_request_reference_filter.rb
deleted file mode 100644
index 5bc63269808..00000000000
--- a/lib/gitlab/markdown/merge_request_reference_filter.rb
+++ /dev/null
@@ -1,74 +0,0 @@
-require 'gitlab/markdown'
-
-module Gitlab
-  module Markdown
-    # HTML filter that replaces merge request references with links. References
-    # to merge requests that do not exist are ignored.
-    #
-    # This filter supports cross-project references.
-    class MergeRequestReferenceFilter < ReferenceFilter
-      include CrossProjectReference
-
-      # Public: Find `!123` merge request references in text
-      #
-      #   MergeRequestReferenceFilter.references_in(text) do |match, merge_request, project_ref|
-      #     "<a href=...>##{merge_request}</a>"
-      #   end
-      #
-      # text - String text to search.
-      #
-      # Yields the String match, the Integer merge request ID, and an optional
-      # String of the external project reference.
-      #
-      # Returns a String replaced with the return of the block.
-      def self.references_in(text)
-        text.gsub(MergeRequest.reference_pattern) do |match|
-          yield match, $~[:merge_request].to_i, $~[:project]
-        end
-      end
-
-      def self.referenced_by(node)
-        { merge_request: LazyReference.new(MergeRequest, node.attr("data-merge-request")) }
-      end
-
-      def call
-        replace_text_nodes_matching(MergeRequest.reference_pattern) do |content|
-          merge_request_link_filter(content)
-        end
-      end
-
-      # Replace `!123` merge request references in text with links to the
-      # referenced merge request's details page.
-      #
-      # text - String text to replace references in.
-      #
-      # Returns a String with `!123` references replaced with links. All links
-      # have `gfm` and `gfm-merge_request` class names attached for styling.
-      def merge_request_link_filter(text)
-        self.class.references_in(text) do |match, id, project_ref|
-          project = self.project_from_ref(project_ref)
-
-          if project && merge_request = project.merge_requests.find_by(iid: id)
-            title = escape_once("Merge Request: #{merge_request.title}")
-            klass = reference_class(:merge_request)
-            data  = data_attribute(project: project.id, merge_request: merge_request.id)
-
-            url = url_for_merge_request(merge_request, project)
-
-            %(<a href="#{url}" #{data}
-                 title="#{title}"
-                 class="#{klass}">#{match}</a>)
-          else
-            match
-          end
-        end
-      end
-
-      def url_for_merge_request(mr, project)
-        h = Gitlab::Application.routes.url_helpers
-        h.namespace_project_merge_request_url(project.namespace, project, mr,
-                                            only_path: context[:only_path])
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/pipeline.rb b/lib/gitlab/markdown/pipeline.rb
new file mode 100644
index 00000000000..8f3f43c0e91
--- /dev/null
+++ b/lib/gitlab/markdown/pipeline.rb
@@ -0,0 +1,34 @@
+require 'banzai'
+
+module Gitlab
+  module Markdown
+    class Pipeline
+      def self.[](name)
+        name ||= :full
+        const_get("#{name.to_s.camelize}Pipeline")
+      end
+
+      def self.filters
+        []
+      end
+
+      def self.transform_context(context)
+        context
+      end
+
+      def self.html_pipeline
+        @html_pipeline ||= HTML::Pipeline.new(filters)
+      end
+
+      class << self
+        %i(call to_document to_html).each do |meth|
+          define_method(meth) do |text, context|
+            context = transform_context(context)
+
+            html_pipeline.send(meth, text, context)
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/markdown/redactor_filter.rb b/lib/gitlab/markdown/redactor_filter.rb
deleted file mode 100644
index a1f3a8a8ebf..00000000000
--- a/lib/gitlab/markdown/redactor_filter.rb
+++ /dev/null
@@ -1,40 +0,0 @@
-require 'gitlab/markdown'
-require 'html/pipeline/filter'
-
-module Gitlab
-  module Markdown
-    # HTML filter that removes references to records that the current user does
-    # not have permission to view.
-    #
-    # Expected to be run in its own post-processing pipeline.
-    #
-    class RedactorFilter < HTML::Pipeline::Filter
-      def call
-        doc.css('a.gfm').each do |node|
-          unless user_can_reference?(node)
-            node.replace(node.text)
-          end
-        end
-
-        doc
-      end
-
-      private
-
-      def user_can_reference?(node)
-        if node.has_attribute?('data-reference-filter')
-          reference_type = node.attr('data-reference-filter')
-          reference_filter = reference_type.constantize
-
-          reference_filter.user_can_reference?(current_user, node, context)
-        else
-          true
-        end
-      end
-
-      def current_user
-        context[:current_user]
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/reference_filter.rb b/lib/gitlab/markdown/reference_filter.rb
deleted file mode 100644
index a4c560f578c..00000000000
--- a/lib/gitlab/markdown/reference_filter.rb
+++ /dev/null
@@ -1,133 +0,0 @@
-require 'active_support/core_ext/string/output_safety'
-require 'gitlab/markdown'
-require 'html/pipeline/filter'
-
-module Gitlab
-  module Markdown
-    # Base class for GitLab Flavored Markdown reference filters.
-    #
-    # References within <pre>, <code>, <a>, and <style> elements are ignored.
-    #
-    # Context options:
-    #   :project (required) - Current project, ignored if reference is cross-project.
-    #   :only_path          - Generate path-only links.
-    class ReferenceFilter < HTML::Pipeline::Filter
-      LazyReference = Struct.new(:klass, :ids) do
-        def self.load(refs)
-          lazy_references, values = refs.partition { |ref| ref.is_a?(self) }
-
-          lazy_values = lazy_references.group_by(&:klass).flat_map do |klass, refs|
-            ids = refs.flat_map(&:ids)
-            klass.where(id: ids)
-          end
-
-          values + lazy_values
-        end
-
-        def load
-          self.klass.where(id: self.ids)
-        end
-      end
-
-      def self.user_can_reference?(user, node, context)
-        if node.has_attribute?('data-project')
-          project_id = node.attr('data-project').to_i
-          return true if project_id == context[:project].try(:id)
-
-          project = Project.find(project_id) rescue nil
-          Ability.abilities.allowed?(user, :read_project, project)
-        else
-          true
-        end
-      end
-
-      def self.referenced_by(node)
-        raise NotImplementedError, "#{self} does not implement #{__method__}"
-      end
-
-      # Returns a data attribute String to attach to a reference link
-      #
-      # attributes - Hash, where the key becomes the data attribute name and the
-      #              value is the data attribute value
-      #
-      # Examples:
-      #
-      #   data_attribute(project: 1, issue: 2)
-      #   # => "data-reference-filter=\"Gitlab::Markdown::SomeReferenceFilter\" data-project=\"1\" data-issue=\"2\""
-      #
-      #   data_attribute(project: 3, merge_request: 4)
-      #   # => "data-reference-filter=\"Gitlab::Markdown::SomeReferenceFilter\" data-project=\"3\" data-merge-request=\"4\""
-      #
-      # Returns a String
-      def data_attribute(attributes = {})
-        attributes[:reference_filter] = self.class.name
-        attributes.map { |key, value| %Q(data-#{key.to_s.dasherize}="#{value}") }.join(" ")
-      end
-
-      def escape_once(html)
-        ERB::Util.html_escape_once(html)
-      end
-
-      def ignore_parents
-        @ignore_parents ||= begin
-          # Don't look for references in text nodes that are children of these
-          # elements.
-          parents = %w(pre code a style)
-          parents << 'blockquote' if context[:ignore_blockquotes]
-          parents.to_set
-        end
-      end
-
-      def ignored_ancestry?(node)
-        has_ancestor?(node, ignore_parents)
-      end
-
-      def project
-        context[:project]
-      end
-
-      def reference_class(type)
-        "gfm gfm-#{type}"
-      end
-
-      # Iterate through the document's text nodes, yielding the current node's
-      # content if:
-      #
-      # * The `project` context value is present AND
-      # * The node's content matches `pattern` AND
-      # * The node is not an ancestor of an ignored node type
-      #
-      # pattern - Regex pattern against which to match the node's content
-      #
-      # Yields the current node's String contents. The result of the block will
-      # replace the node's existing content and update the current document.
-      #
-      # Returns the updated Nokogiri::HTML::DocumentFragment object.
-      def replace_text_nodes_matching(pattern)
-        return doc if project.nil?
-
-        search_text_nodes(doc).each do |node|
-          next if ignored_ancestry?(node)
-          next unless node.text =~ pattern
-
-          content = node.to_html
-
-          html = yield content
-
-          next if html == content
-
-          node.replace(html)
-        end
-
-        doc
-      end
-
-      # Ensure that a :project key exists in context
-      #
-      # Note that while the key might exist, its value could be nil!
-      def validate
-        needs :project
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/reference_gatherer_filter.rb b/lib/gitlab/markdown/reference_gatherer_filter.rb
deleted file mode 100644
index 00f983675e6..00000000000
--- a/lib/gitlab/markdown/reference_gatherer_filter.rb
+++ /dev/null
@@ -1,63 +0,0 @@
-require 'gitlab/markdown'
-require 'html/pipeline/filter'
-
-module Gitlab
-  module Markdown
-    # HTML filter that gathers all referenced records that the current user has
-    # permission to view.
-    #
-    # Expected to be run in its own post-processing pipeline.
-    #
-    class ReferenceGathererFilter < HTML::Pipeline::Filter
-      def initialize(*)
-        super
-
-        result[:references] ||= Hash.new { |hash, type| hash[type] = [] }
-      end
-
-      def call
-        doc.css('a.gfm').each do |node|
-          gather_references(node)
-        end
-
-        load_lazy_references unless context[:load_lazy_references] == false
-
-        doc
-      end
-
-      private
-
-      def gather_references(node)
-        return unless node.has_attribute?('data-reference-filter')
-
-        reference_type = node.attr('data-reference-filter')
-        reference_filter = reference_type.constantize
-
-        return if context[:reference_filter] && reference_filter != context[:reference_filter]
-
-        return unless reference_filter.user_can_reference?(current_user, node, context)
-
-        references = reference_filter.referenced_by(node)
-        return unless references
-
-        references.each do |type, values|
-          Array.wrap(values).each do |value|
-            result[:references][type] << value
-          end
-        end
-      end
-
-      # Will load all references of one type using one query.
-      def load_lazy_references
-        refs = result[:references]
-        refs.each do |type, values|
-          refs[type] = ReferenceFilter::LazyReference.load(values)
-        end
-      end
-
-      def current_user
-        context[:current_user]
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/relative_link_filter.rb b/lib/gitlab/markdown/relative_link_filter.rb
deleted file mode 100644
index 6ee3d1ce039..00000000000
--- a/lib/gitlab/markdown/relative_link_filter.rb
+++ /dev/null
@@ -1,157 +0,0 @@
-require 'gitlab/markdown'
-require 'html/pipeline/filter'
-require 'uri'
-
-module Gitlab
-  module Markdown
-    # HTML filter that "fixes" relative links to files in a repository.
-    #
-    # Context options:
-    #   :commit
-    #   :project
-    #   :project_wiki
-    #   :ref
-    #   :requested_path
-    class RelativeLinkFilter < HTML::Pipeline::Filter
-      def call
-        return doc unless linkable_files?
-
-        doc.search('a').each do |el|
-          process_link_attr el.attribute('href')
-        end
-
-        doc.search('img').each do |el|
-          process_link_attr el.attribute('src')
-        end
-
-        doc
-      end
-
-      protected
-
-      def linkable_files?
-        context[:project_wiki].nil? && repository.try(:exists?) && !repository.empty?
-      end
-
-      def process_link_attr(html_attr)
-        return if html_attr.blank?
-
-        uri = URI(html_attr.value)
-        if uri.relative? && uri.path.present?
-          html_attr.value = rebuild_relative_uri(uri).to_s
-        end
-      rescue URI::Error
-        # noop
-      end
-
-      def rebuild_relative_uri(uri)
-        file_path = relative_file_path(uri.path)
-
-        uri.path = [
-          relative_url_root,
-          context[:project].path_with_namespace,
-          path_type(file_path),
-          ref || 'master',  # assume that if no ref exists we can point to master
-          file_path
-        ].compact.join('/').squeeze('/').chomp('/')
-
-        uri
-      end
-
-      def relative_file_path(path)
-        nested_path = build_relative_path(path, context[:requested_path])
-        file_exists?(nested_path) ? nested_path : path
-      end
-
-      # Convert a relative path into its correct location based on the currently
-      # requested path
-      #
-      # path         - Relative path String
-      # request_path - Currently-requested path String
-      #
-      # Examples:
-      #
-      #   # File in the same directory as the current path
-      #   build_relative_path("users.md", "doc/api/README.md")
-      #   # => "doc/api/users.md"
-      #
-      #   # File in the same directory, which is also the current path
-      #   build_relative_path("users.md", "doc/api")
-      #   # => "doc/api/users.md"
-      #
-      #   # Going up one level to a different directory
-      #   build_relative_path("../update/7.14-to-8.0.md", "doc/api/README.md")
-      #   # => "doc/update/7.14-to-8.0.md"
-      #
-      # Returns a String
-      def build_relative_path(path, request_path)
-        return request_path if path.empty?
-        return path unless request_path
-
-        parts = request_path.split('/')
-        parts.pop if path_type(request_path) != 'tree'
-
-        while parts.length > 1 && path.start_with?('../')
-          parts.pop
-          path.sub!('../', '')
-        end
-
-        parts.push(path).join('/')
-      end
-
-      def file_exists?(path)
-        return false if path.nil?
-        repository.blob_at(current_sha, path).present? ||
-          repository.tree(current_sha, path).entries.any?
-      end
-
-      # Get the type of the given path
-      #
-      # path - String path to check
-      #
-      # Examples:
-      #
-      #   path_type('doc/README.md') # => 'blob'
-      #   path_type('doc/logo.png')  # => 'raw'
-      #   path_type('doc/api')       # => 'tree'
-      #
-      # Returns a String
-      def path_type(path)
-        unescaped_path = Addressable::URI.unescape(path)
-
-        if tree?(unescaped_path)
-          'tree'
-        elsif image?(unescaped_path)
-          'raw'
-        else
-          'blob'
-        end
-      end
-
-      def tree?(path)
-        repository.tree(current_sha, path).entries.any?
-      end
-
-      def image?(path)
-        repository.blob_at(current_sha, path).try(:image?)
-      end
-
-      def current_sha
-        context[:commit].try(:id) ||
-          ref ? repository.commit(ref).try(:sha) : repository.head_commit.sha
-      end
-
-      def relative_url_root
-        Gitlab.config.gitlab.relative_url_root.presence || '/'
-      end
-
-      def ref
-        context[:ref]
-      end
-
-      def repository
-        context[:project].try(:repository)
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/sanitization_filter.rb b/lib/gitlab/markdown/sanitization_filter.rb
deleted file mode 100644
index e368de7d848..00000000000
--- a/lib/gitlab/markdown/sanitization_filter.rb
+++ /dev/null
@@ -1,84 +0,0 @@
-require 'gitlab/markdown'
-require 'html/pipeline/filter'
-require 'html/pipeline/sanitization_filter'
-
-module Gitlab
-  module Markdown
-    # Sanitize HTML
-    #
-    # Extends HTML::Pipeline::SanitizationFilter with a custom whitelist.
-    class SanitizationFilter < HTML::Pipeline::SanitizationFilter
-      def whitelist
-        # Descriptions are more heavily sanitized, allowing only a few elements.
-        # See http://git.io/vkuAN
-        if pipeline == :description
-          whitelist = LIMITED
-          whitelist[:elements] -= %w(pre code img ol ul li)
-        else
-          whitelist = super
-        end
-
-        customize_whitelist(whitelist)
-
-        whitelist
-      end
-
-      private
-
-      def pipeline
-        context[:pipeline] || :default
-      end
-
-      def customized?(transformers)
-        transformers.last.source_location[0] == __FILE__
-      end
-
-      def customize_whitelist(whitelist)
-        # Only push these customizations once
-        return if customized?(whitelist[:transformers])
-
-        # Allow code highlighting
-        whitelist[:attributes]['pre'] = %w(class)
-        whitelist[:attributes]['span'] = %w(class)
-
-        # Allow table alignment
-        whitelist[:attributes]['th'] = %w(style)
-        whitelist[:attributes]['td'] = %w(style)
-
-        # Allow span elements
-        whitelist[:elements].push('span')
-
-        # Remove `rel` attribute from `a` elements
-        whitelist[:transformers].push(remove_rel)
-
-        # Remove `class` attribute from non-highlight spans
-        whitelist[:transformers].push(clean_spans)
-
-        whitelist
-      end
-
-      def remove_rel
-        lambda do |env|
-          if env[:node_name] == 'a'
-            env[:node].remove_attribute('rel')
-          end
-        end
-      end
-
-      def clean_spans
-        lambda do |env|
-          node = env[:node]
-
-          return unless node.name == 'span'
-          return unless node.has_attribute?('class')
-
-          unless has_ancestor?(node, 'pre')
-            node.remove_attribute('class')
-          end
-
-          { node_whitelist: [node] }
-        end
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/snippet_reference_filter.rb b/lib/gitlab/markdown/snippet_reference_filter.rb
deleted file mode 100644
index f783f951711..00000000000
--- a/lib/gitlab/markdown/snippet_reference_filter.rb
+++ /dev/null
@@ -1,74 +0,0 @@
-require 'gitlab/markdown'
-
-module Gitlab
-  module Markdown
-    # HTML filter that replaces snippet references with links. References to
-    # snippets that do not exist are ignored.
-    #
-    # This filter supports cross-project references.
-    class SnippetReferenceFilter < ReferenceFilter
-      include CrossProjectReference
-
-      # Public: Find `$123` snippet references in text
-      #
-      #   SnippetReferenceFilter.references_in(text) do |match, snippet|
-      #     "<a href=...>$#{snippet}</a>"
-      #   end
-      #
-      # text - String text to search.
-      #
-      # Yields the String match, the Integer snippet ID, and an optional String
-      # of the external project reference.
-      #
-      # Returns a String replaced with the return of the block.
-      def self.references_in(text)
-        text.gsub(Snippet.reference_pattern) do |match|
-          yield match, $~[:snippet].to_i, $~[:project]
-        end
-      end
-
-      def self.referenced_by(node)
-        { snippet: LazyReference.new(Snippet, node.attr("data-snippet")) }
-      end
-
-      def call
-        replace_text_nodes_matching(Snippet.reference_pattern) do |content|
-          snippet_link_filter(content)
-        end
-      end
-
-      # Replace `$123` snippet references in text with links to the referenced
-      # snippets's details page.
-      #
-      # text - String text to replace references in.
-      #
-      # Returns a String with `$123` references replaced with links. All links
-      # have `gfm` and `gfm-snippet` class names attached for styling.
-      def snippet_link_filter(text)
-        self.class.references_in(text) do |match, id, project_ref|
-          project = self.project_from_ref(project_ref)
-
-          if project && snippet = project.snippets.find_by(id: id)
-            title = escape_once("Snippet: #{snippet.title}")
-            klass = reference_class(:snippet)
-            data  = data_attribute(project: project.id, snippet: snippet.id)
-
-            url = url_for_snippet(snippet, project)
-
-            %(<a href="#{url}" #{data}
-                 title="#{title}"
-                 class="#{klass}">#{match}</a>)
-          else
-            match
-          end
-        end
-      end
-
-      def url_for_snippet(snippet, project)
-        h = Gitlab::Application.routes.url_helpers
-        h.namespace_project_snippet_url(project.namespace, project, snippet,
-                                        only_path: context[:only_path])
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/syntax_highlight_filter.rb b/lib/gitlab/markdown/syntax_highlight_filter.rb
deleted file mode 100644
index 8597e02f0de..00000000000
--- a/lib/gitlab/markdown/syntax_highlight_filter.rb
+++ /dev/null
@@ -1,45 +0,0 @@
-require 'gitlab/markdown'
-require 'html/pipeline/filter'
-require 'rouge/plugins/redcarpet'
-
-module Gitlab
-  module Markdown
-    # HTML Filter to highlight fenced code blocks
-    #
-    class SyntaxHighlightFilter < HTML::Pipeline::Filter
-      include Rouge::Plugins::Redcarpet
-
-      def call
-        doc.search('pre > code').each do |node|
-          highlight_node(node)
-        end
-
-        doc
-      end
-
-      def highlight_node(node)
-        language = node.attr('class')
-        code     = node.text
-
-        begin
-          highlighted = block_code(code, language)
-        rescue
-          # Gracefully handle syntax highlighter bugs/errors to ensure
-          # users can still access an issue/comment/etc.
-          highlighted = "<pre>#{code}</pre>"
-        end
-
-        # Replace the parent `pre` element with the entire highlighted block
-        node.parent.replace(highlighted)
-      end
-
-      private
-
-      # Override Rouge::Plugins::Redcarpet#rouge_formatter
-      def rouge_formatter(lexer)
-        Rouge::Formatters::HTMLGitlab.new(
-          cssclass: "code highlight js-syntax-highlight #{lexer.tag}")
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/table_of_contents_filter.rb b/lib/gitlab/markdown/table_of_contents_filter.rb
deleted file mode 100644
index bbb3bf7fc8b..00000000000
--- a/lib/gitlab/markdown/table_of_contents_filter.rb
+++ /dev/null
@@ -1,63 +0,0 @@
-require 'gitlab/markdown'
-require 'html/pipeline/filter'
-
-module Gitlab
-  module Markdown
-    # HTML filter that adds an anchor child element to all Headers in a
-    # document, so that they can be linked to.
-    #
-    # Generates the Table of Contents with links to each header. See Results.
-    #
-    # Based on HTML::Pipeline::TableOfContentsFilter.
-    #
-    # Context options:
-    #   :no_header_anchors - Skips all processing done by this filter.
-    #
-    # Results:
-    #   :toc - String containing Table of Contents data as a `ul` element with
-    #          `li` child elements.
-    class TableOfContentsFilter < HTML::Pipeline::Filter
-      PUNCTUATION_REGEXP = /[^\p{Word}\- ]/u
-
-      def call
-        return doc if context[:no_header_anchors]
-
-        result[:toc] = ""
-
-        headers = Hash.new(0)
-
-        doc.css('h1, h2, h3, h4, h5, h6').each do |node|
-          text = node.text
-
-          id = text.downcase
-          id.gsub!(PUNCTUATION_REGEXP, '') # remove punctuation
-          id.gsub!(' ', '-') # replace spaces with dash
-          id.squeeze!('-') # replace multiple dashes with one
-
-          uniq = (headers[id] > 0) ? "-#{headers[id]}" : ''
-          headers[id] += 1
-
-          if header_content = node.children.first
-            href = "#{id}#{uniq}"
-            push_toc(href, text)
-            header_content.add_previous_sibling(anchor_tag(href))
-          end
-        end
-
-        result[:toc] = %Q{<ul class="section-nav">\n#{result[:toc]}</ul>} unless result[:toc].empty?
-
-        doc
-      end
-
-      private
-
-      def anchor_tag(href)
-        %Q{<a id="#{href}" class="anchor" href="##{href}" aria-hidden="true"></a>}
-      end
-
-      def push_toc(href, text)
-        result[:toc] << %Q{<li><a href="##{href}">#{text}</a></li>\n}
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/task_list_filter.rb b/lib/gitlab/markdown/task_list_filter.rb
deleted file mode 100644
index 2f133ae8500..00000000000
--- a/lib/gitlab/markdown/task_list_filter.rb
+++ /dev/null
@@ -1,24 +0,0 @@
-require 'gitlab/markdown'
-require 'task_list/filter'
-
-module Gitlab
-  module Markdown
-    # Work around a bug in the default TaskList::Filter that adds a `task-list`
-    # class to every list element, regardless of whether or not it contains a
-    # task list.
-    #
-    # This is a (hopefully) temporary fix, pending a new release of the
-    # task_list gem.
-    #
-    # See https://github.com/github/task_list/pull/60
-    class TaskListFilter < TaskList::Filter
-      def add_css_class(node, *new_class_names)
-        if new_class_names.include?('task-list')
-          super if node.children.any? { |c| c['class'] == 'task-list-item' }
-        else
-          super
-        end
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/upload_link_filter.rb b/lib/gitlab/markdown/upload_link_filter.rb
deleted file mode 100644
index fbada73ab86..00000000000
--- a/lib/gitlab/markdown/upload_link_filter.rb
+++ /dev/null
@@ -1,47 +0,0 @@
-require 'gitlab/markdown'
-require 'html/pipeline/filter'
-require 'uri'
-
-module Gitlab
-  module Markdown
-    # HTML filter that "fixes" relative upload links to files.
-    # Context options:
-    #   :project (required) - Current project
-    #
-    class UploadLinkFilter < HTML::Pipeline::Filter
-      def call
-        doc.search('a').each do |el|
-          process_link_attr el.attribute('href')
-        end
-
-        doc.search('img').each do |el|
-          process_link_attr el.attribute('src')
-        end
-
-        doc
-      end
-
-      protected
-
-      def process_link_attr(html_attr)
-        return if html_attr.blank?
-
-        uri = html_attr.value
-        if uri.starts_with?("/uploads/")
-          html_attr.value = build_url(uri).to_s
-        end
-      end
-
-      def build_url(uri)
-        File.join(Gitlab.config.gitlab.url, context[:project].path_with_namespace, uri)
-      end
-
-      # Ensure that a :project key exists in context
-      #
-      # Note that while the key might exist, its value could be nil!
-      def validate
-        needs :project
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/markdown/user_reference_filter.rb b/lib/gitlab/markdown/user_reference_filter.rb
deleted file mode 100644
index 2a594e1662e..00000000000
--- a/lib/gitlab/markdown/user_reference_filter.rb
+++ /dev/null
@@ -1,122 +0,0 @@
-require 'gitlab/markdown'
-
-module Gitlab
-  module Markdown
-    # HTML filter that replaces user or group references with links.
-    #
-    # A special `@all` reference is also supported.
-    class UserReferenceFilter < ReferenceFilter
-      # Public: Find `@user` user references in text
-      #
-      #   UserReferenceFilter.references_in(text) do |match, username|
-      #     "<a href=...>@#{user}</a>"
-      #   end
-      #
-      # text - String text to search.
-      #
-      # Yields the String match, and the String user name.
-      #
-      # Returns a String replaced with the return of the block.
-      def self.references_in(text)
-        text.gsub(User.reference_pattern) do |match|
-          yield match, $~[:user]
-        end
-      end
-
-      def self.referenced_by(node)
-        if node.has_attribute?('data-group')
-          group = Group.find(node.attr('data-group')) rescue nil
-          return unless group
-
-          { user: group.users }
-        elsif node.has_attribute?('data-user')
-          { user: LazyReference.new(User, node.attr('data-user')) }
-        elsif node.has_attribute?('data-project')
-          project = Project.find(node.attr('data-project')) rescue nil
-          return unless project
-
-          { user: project.team.members.flatten }
-        end
-      end
-
-      def self.user_can_reference?(user, node, context)
-        if node.has_attribute?('data-group')
-          group = Group.find(node.attr('data-group')) rescue nil
-          Ability.abilities.allowed?(user, :read_group, group)
-        else
-          super
-        end
-      end
-
-      def call
-        replace_text_nodes_matching(User.reference_pattern) do |content|
-          user_link_filter(content)
-        end
-      end
-
-      # Replace `@user` user references in text with links to the referenced
-      # user's profile page.
-      #
-      # text - String text to replace references in.
-      #
-      # Returns a String with `@user` references replaced with links. All links
-      # have `gfm` and `gfm-project_member` class names attached for styling.
-      def user_link_filter(text)
-        self.class.references_in(text) do |match, username|
-          if username == 'all'
-            link_to_all
-          elsif namespace = Namespace.find_by(path: username)
-            link_to_namespace(namespace) || match
-          else
-            match
-          end
-        end
-      end
-
-      private
-
-      def urls
-        Gitlab::Application.routes.url_helpers
-      end
-
-      def link_class
-        reference_class(:project_member)
-      end
-
-      def link_to_all
-        project = context[:project]
-
-        url = urls.namespace_project_url(project.namespace, project,
-                                         only_path: context[:only_path])
-        data = data_attribute(project: project.id)
-
-        text = User.reference_prefix + 'all'
-        %(<a href="#{url}" #{data} class="#{link_class}">#{text}</a>)
-      end
-
-      def link_to_namespace(namespace)
-        if namespace.is_a?(Group)
-          link_to_group(namespace.path, namespace)
-        else
-          link_to_user(namespace.path, namespace)
-        end
-      end
-
-      def link_to_group(group, namespace)
-        url = urls.group_url(group, only_path: context[:only_path])
-        data = data_attribute(group: namespace.id)
-
-        text = Group.reference_prefix + group
-        %(<a href="#{url}" #{data} class="#{link_class}">#{text}</a>)
-      end
-
-      def link_to_user(user, namespace)
-        url = urls.user_url(user, only_path: context[:only_path])
-        data = data_attribute(user: namespace.owner_id)
-
-        text = User.reference_prefix + user
-        %(<a href="#{url}" #{data} class="#{link_class}">#{text}</a>)
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/metrics.rb b/lib/gitlab/metrics.rb
new file mode 100644
index 00000000000..ee88ab34d6c
--- /dev/null
+++ b/lib/gitlab/metrics.rb
@@ -0,0 +1,102 @@
+module Gitlab
+  module Metrics
+    extend Gitlab::CurrentSettings
+
+    RAILS_ROOT   = Rails.root.to_s
+    METRICS_ROOT = Rails.root.join('lib', 'gitlab', 'metrics').to_s
+    PATH_REGEX   = /^#{RAILS_ROOT}\/?/
+
+    def self.settings
+      @settings ||= {
+        enabled:               current_application_settings[:metrics_enabled],
+        pool_size:             current_application_settings[:metrics_pool_size],
+        timeout:               current_application_settings[:metrics_timeout],
+        method_call_threshold: current_application_settings[:metrics_method_call_threshold],
+        host:                  current_application_settings[:metrics_host],
+        username:              current_application_settings[:metrics_username],
+        password:              current_application_settings[:metrics_password],
+        port:                  current_application_settings[:metrics_port]
+      }
+    end
+
+    def self.enabled?
+      settings[:enabled] || false
+    end
+
+    def self.mri?
+      RUBY_ENGINE == 'ruby'
+    end
+
+    def self.method_call_threshold
+      # This is memoized since this method is called for every instrumented
+      # method. Loading data from an external cache on every method call slows
+      # things down too much.
+      @method_call_threshold ||= settings[:method_call_threshold]
+    end
+
+    def self.pool
+      @pool
+    end
+
+    # Returns a relative path and line number based on the last application call
+    # frame.
+    def self.last_relative_application_frame
+      frame = caller_locations.find do |l|
+        l.path.start_with?(RAILS_ROOT) && !l.path.start_with?(METRICS_ROOT)
+      end
+
+      if frame
+        return frame.path.sub(PATH_REGEX, ''), frame.lineno
+      else
+        return nil, nil
+      end
+    end
+
+    def self.submit_metrics(metrics)
+      prepared = prepare_metrics(metrics)
+
+      pool.with do |connection|
+        prepared.each do |metric|
+          begin
+            connection.write_points([metric])
+          rescue StandardError
+          end
+        end
+      end
+    end
+
+    def self.prepare_metrics(metrics)
+      metrics.map do |hash|
+        new_hash = hash.symbolize_keys
+
+        new_hash[:tags].each do |key, value|
+          if value.blank?
+            new_hash[:tags].delete(key)
+          else
+            new_hash[:tags][key] = escape_value(value)
+          end
+        end
+
+        new_hash
+      end
+    end
+
+    def self.escape_value(value)
+      value.to_s.gsub('=', '\\=')
+    end
+
+    # When enabled this should be set before being used as the usual pattern
+    # "@foo ||= bar" is _not_ thread-safe.
+    if enabled?
+      @pool = ConnectionPool.new(size: settings[:pool_size], timeout: settings[:timeout]) do
+        host = settings[:host]
+        user = settings[:username]
+        pw   = settings[:password]
+        port = settings[:port]
+
+        InfluxDB::Client.
+          new(udp: { host: host, port: port }, username: user, password: pw)
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/metrics/delta.rb b/lib/gitlab/metrics/delta.rb
new file mode 100644
index 00000000000..bcf28eed84d
--- /dev/null
+++ b/lib/gitlab/metrics/delta.rb
@@ -0,0 +1,32 @@
+module Gitlab
+  module Metrics
+    # Class for calculating the difference between two numeric values.
+    #
+    # Every call to `compared_with` updates the internal value. This makes it
+    # possible to use a single Delta instance to calculate the delta over time
+    # of an ever increasing number.
+    #
+    # Example usage:
+    #
+    #     delta = Delta.new(0)
+    #
+    #     delta.compared_with(10) # => 10
+    #     delta.compared_with(15) # => 5
+    #     delta.compared_with(20) # => 5
+    class Delta
+      def initialize(value = 0)
+        @value = value
+      end
+
+      # new_value - The value to compare with as a Numeric.
+      #
+      # Returns a new Numeric (depending on the type of `new_value`).
+      def compared_with(new_value)
+        delta  = new_value - @value
+        @value = new_value
+
+        delta
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/metrics/instrumentation.rb b/lib/gitlab/metrics/instrumentation.rb
new file mode 100644
index 00000000000..d9fce2e6758
--- /dev/null
+++ b/lib/gitlab/metrics/instrumentation.rb
@@ -0,0 +1,148 @@
+module Gitlab
+  module Metrics
+    # Module for instrumenting methods.
+    #
+    # This module allows instrumenting of methods without having to actually
+    # alter the target code (e.g. by including modules).
+    #
+    # Example usage:
+    #
+    #     Gitlab::Metrics::Instrumentation.instrument_method(User, :by_login)
+    module Instrumentation
+      SERIES = 'method_calls'
+
+      def self.configure
+        yield self
+      end
+
+      # Instruments a class method.
+      #
+      # mod  - The module to instrument as a Module/Class.
+      # name - The name of the method to instrument.
+      def self.instrument_method(mod, name)
+        instrument(:class, mod, name)
+      end
+
+      # Instruments an instance method.
+      #
+      # mod  - The module to instrument as a Module/Class.
+      # name - The name of the method to instrument.
+      def self.instrument_instance_method(mod, name)
+        instrument(:instance, mod, name)
+      end
+
+      # Recursively instruments all subclasses of the given root module.
+      #
+      # This can be used to for example instrument all ActiveRecord models (as
+      # these all inherit from ActiveRecord::Base).
+      #
+      # This method can optionally take a block to pass to `instrument_methods`
+      # and `instrument_instance_methods`.
+      #
+      # root - The root module for which to instrument subclasses. The root
+      #        module itself is not instrumented.
+      def self.instrument_class_hierarchy(root, &block)
+        visit = root.subclasses
+
+        until visit.empty?
+          klass = visit.pop
+
+          instrument_methods(klass, &block)
+          instrument_instance_methods(klass, &block)
+
+          klass.subclasses.each { |c| visit << c }
+        end
+      end
+
+      # Instruments all public methods of a module.
+      #
+      # This method optionally takes a block that can be used to determine if a
+      # method should be instrumented or not. The block is passed the receiving
+      # module and an UnboundMethod. If the block returns a non truthy value the
+      # method is not instrumented.
+      #
+      # mod - The module to instrument.
+      def self.instrument_methods(mod)
+        mod.public_methods(false).each do |name|
+          method = mod.method(name)
+
+          if method.owner == mod.singleton_class
+            if !block_given? || block_given? && yield(mod, method)
+              instrument_method(mod, name)
+            end
+          end
+        end
+      end
+
+      # Instruments all public instance methods of a module.
+      #
+      # See `instrument_methods` for more information.
+      #
+      # mod - The module to instrument.
+      def self.instrument_instance_methods(mod)
+        mod.public_instance_methods(false).each do |name|
+          method = mod.instance_method(name)
+
+          if method.owner == mod
+            if !block_given? || block_given? && yield(mod, method)
+              instrument_instance_method(mod, name)
+            end
+          end
+        end
+      end
+
+      # Instruments a method.
+      #
+      # type - The type (:class or :instance) of method to instrument.
+      # mod  - The module containing the method.
+      # name - The name of the method to instrument.
+      def self.instrument(type, mod, name)
+        return unless Metrics.enabled?
+
+        name       = name.to_sym
+        alias_name = :"_original_#{name}"
+        target     = type == :instance ? mod : mod.singleton_class
+
+        if type == :instance
+          target = mod
+          label  = "#{mod.name}##{name}"
+        else
+          target = mod.singleton_class
+          label  = "#{mod.name}.#{name}"
+        end
+
+        target.class_eval <<-EOF, __FILE__, __LINE__ + 1
+          alias_method #{alias_name.inspect}, #{name.inspect}
+
+          def #{name}(*args, &block)
+            trans = Gitlab::Metrics::Instrumentation.transaction
+
+            if trans
+              start    = Time.now
+              retval   = __send__(#{alias_name.inspect}, *args, &block)
+              duration = (Time.now - start) * 1000.0
+
+              if duration >= Gitlab::Metrics.method_call_threshold
+                trans.increment(:method_duration, duration)
+
+                trans.add_metric(Gitlab::Metrics::Instrumentation::SERIES,
+                                 { duration: duration },
+                                 method: #{label.inspect})
+              end
+
+              retval
+            else
+              __send__(#{alias_name.inspect}, *args, &block)
+            end
+          end
+        EOF
+      end
+
+      # Small layer of indirection to make it easier to stub out the current
+      # transaction.
+      def self.transaction
+        Transaction.current
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/metrics/metric.rb b/lib/gitlab/metrics/metric.rb
new file mode 100644
index 00000000000..7ea9555cc8c
--- /dev/null
+++ b/lib/gitlab/metrics/metric.rb
@@ -0,0 +1,28 @@
+module Gitlab
+  module Metrics
+    # Class for storing details of a single metric (label, value, etc).
+    class Metric
+      attr_reader :series, :values, :tags, :created_at
+
+      # series - The name of the series (as a String) to store the metric in.
+      # values - A Hash containing the values to store.
+      # tags   - A Hash containing extra tags to add to the metrics.
+      def initialize(series, values, tags = {})
+        @values     = values
+        @series     = series
+        @tags       = tags
+        @created_at = Time.now.utc
+      end
+
+      # Returns a Hash in a format that can be directly written to InfluxDB.
+      def to_hash
+        {
+          series:    @series,
+          tags:      @tags,
+          values:    @values,
+          timestamp: @created_at.to_i * 1_000_000_000
+        }
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/metrics/rack_middleware.rb b/lib/gitlab/metrics/rack_middleware.rb
new file mode 100644
index 00000000000..5c0587c4c51
--- /dev/null
+++ b/lib/gitlab/metrics/rack_middleware.rb
@@ -0,0 +1,49 @@
+module Gitlab
+  module Metrics
+    # Rack middleware for tracking Rails requests.
+    class RackMiddleware
+      CONTROLLER_KEY = 'action_controller.instance'
+
+      def initialize(app)
+        @app = app
+      end
+
+      # env - A Hash containing Rack environment details.
+      def call(env)
+        trans  = transaction_from_env(env)
+        retval = nil
+
+        begin
+          retval = trans.run { @app.call(env) }
+
+        # Even in the event of an error we want to submit any metrics we
+        # might've gathered up to this point.
+        ensure
+          if env[CONTROLLER_KEY]
+            tag_controller(trans, env)
+          end
+
+          trans.finish
+        end
+
+        retval
+      end
+
+      def transaction_from_env(env)
+        trans = Transaction.new
+
+        trans.add_tag(:request_method, env['REQUEST_METHOD'])
+        trans.add_tag(:request_uri, env['REQUEST_URI'])
+
+        trans
+      end
+
+      def tag_controller(trans, env)
+        controller = env[CONTROLLER_KEY]
+        label      = "#{controller.class.name}##{controller.action_name}"
+
+        trans.add_tag(:action, label)
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/metrics/sampler.rb b/lib/gitlab/metrics/sampler.rb
new file mode 100644
index 00000000000..1ea425bc904
--- /dev/null
+++ b/lib/gitlab/metrics/sampler.rb
@@ -0,0 +1,107 @@
+module Gitlab
+  module Metrics
+    # Class that sends certain metrics to InfluxDB at a specific interval.
+    #
+    # This class is used to gather statistics that can't be directly associated
+    # with a transaction such as system memory usage, garbage collection
+    # statistics, etc.
+    class Sampler
+      # interval - The sampling interval in seconds.
+      def initialize(interval = 15)
+        @interval = interval
+        @metrics  = []
+
+        @last_minor_gc = Delta.new(GC.stat[:minor_gc_count])
+        @last_major_gc = Delta.new(GC.stat[:major_gc_count])
+
+        if Gitlab::Metrics.mri?
+          require 'allocations'
+
+          Allocations.start
+        end
+      end
+
+      def start
+        Thread.new do
+          Thread.current.abort_on_exception = true
+
+          loop do
+            sleep(@interval)
+
+            sample
+          end
+        end
+      end
+
+      def sample
+        sample_memory_usage
+        sample_file_descriptors
+        sample_objects
+        sample_gc
+
+        flush
+      ensure
+        GC::Profiler.clear
+        @metrics.clear
+      end
+
+      def flush
+        Metrics.submit_metrics(@metrics.map(&:to_hash))
+      end
+
+      def sample_memory_usage
+        add_metric('memory_usage', value: System.memory_usage)
+      end
+
+      def sample_file_descriptors
+        add_metric('file_descriptors', value: System.file_descriptor_count)
+      end
+
+      if Metrics.mri?
+        def sample_objects
+          sample = Allocations.to_hash
+          counts = sample.each_with_object({}) do |(klass, count), hash|
+            hash[klass.name] = count
+          end
+
+          # Symbols aren't allocated so we'll need to add those manually.
+          counts['Symbol'] = Symbol.all_symbols.length
+
+          counts.each do |name, count|
+            add_metric('object_counts', { count: count }, type: name)
+          end
+        end
+      else
+        def sample_objects
+        end
+      end
+
+      def sample_gc
+        time  = GC::Profiler.total_time * 1000.0
+        stats = GC.stat.merge(total_time: time)
+
+        # We want the difference of GC runs compared to the last sample, not the
+        # total amount since the process started.
+        stats[:minor_gc_count] =
+          @last_minor_gc.compared_with(stats[:minor_gc_count])
+
+        stats[:major_gc_count] =
+          @last_major_gc.compared_with(stats[:major_gc_count])
+
+        stats[:count] = stats[:minor_gc_count] + stats[:major_gc_count]
+
+        add_metric('gc_statistics', stats)
+      end
+
+      def add_metric(series, values, tags = {})
+        prefix = sidekiq? ? 'sidekiq_' : 'rails_'
+
+        @metrics << Metric.new("#{prefix}#{series}", values, tags)
+      end
+
+      def sidekiq?
+        Sidekiq.server?
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/metrics/sidekiq_middleware.rb b/lib/gitlab/metrics/sidekiq_middleware.rb
new file mode 100644
index 00000000000..ad441decfa2
--- /dev/null
+++ b/lib/gitlab/metrics/sidekiq_middleware.rb
@@ -0,0 +1,23 @@
+module Gitlab
+  module Metrics
+    # Sidekiq middleware for tracking jobs.
+    #
+    # This middleware is intended to be used as a server-side middleware.
+    class SidekiqMiddleware
+      def call(worker, message, queue)
+        trans = Transaction.new
+
+        begin
+          trans.run { yield }
+        ensure
+          tag_worker(trans, worker)
+          trans.finish
+        end
+      end
+
+      def tag_worker(trans, worker)
+        trans.add_tag(:action, "#{worker.class.name}#perform")
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/metrics/subscribers/action_view.rb b/lib/gitlab/metrics/subscribers/action_view.rb
new file mode 100644
index 00000000000..7c0105d543a
--- /dev/null
+++ b/lib/gitlab/metrics/subscribers/action_view.rb
@@ -0,0 +1,54 @@
+module Gitlab
+  module Metrics
+    module Subscribers
+      # Class for tracking the rendering timings of views.
+      class ActionView < ActiveSupport::Subscriber
+        attach_to :action_view
+
+        SERIES = 'views'
+
+        def render_template(event)
+          track(event) if current_transaction
+        end
+
+        alias_method :render_view, :render_template
+
+        private
+
+        def track(event)
+          values = values_for(event)
+          tags   = tags_for(event)
+
+          current_transaction.increment(:view_duration, event.duration)
+          current_transaction.add_metric(SERIES, values, tags)
+        end
+
+        def relative_path(path)
+          path.gsub(/^#{Rails.root.to_s}\/?/, '')
+        end
+
+        def values_for(event)
+          { duration: event.duration }
+        end
+
+        def tags_for(event)
+          path = relative_path(event.payload[:identifier])
+          tags = { view: path }
+
+          file, line = Metrics.last_relative_application_frame
+
+          if file and line
+            tags[:file] = file
+            tags[:line] = line
+          end
+
+          tags
+        end
+
+        def current_transaction
+          Transaction.current
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/metrics/subscribers/active_record.rb b/lib/gitlab/metrics/subscribers/active_record.rb
new file mode 100644
index 00000000000..8008b3bc895
--- /dev/null
+++ b/lib/gitlab/metrics/subscribers/active_record.rb
@@ -0,0 +1,22 @@
+module Gitlab
+  module Metrics
+    module Subscribers
+      # Class for tracking the total query duration of a transaction.
+      class ActiveRecord < ActiveSupport::Subscriber
+        attach_to :active_record
+
+        def sql(event)
+          return unless current_transaction
+
+          current_transaction.increment(:sql_duration, event.duration)
+        end
+
+        private
+
+        def current_transaction
+          Transaction.current
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/metrics/system.rb b/lib/gitlab/metrics/system.rb
new file mode 100644
index 00000000000..83371265278
--- /dev/null
+++ b/lib/gitlab/metrics/system.rb
@@ -0,0 +1,35 @@
+module Gitlab
+  module Metrics
+    # Module for gathering system/process statistics such as the memory usage.
+    #
+    # This module relies on the /proc filesystem being available. If /proc is
+    # not available the methods of this module will be stubbed.
+    module System
+      if File.exist?('/proc')
+        # Returns the current process' memory usage in bytes.
+        def self.memory_usage
+          mem   = 0
+          match = File.read('/proc/self/status').match(/VmRSS:\s+(\d+)/)
+
+          if match and match[1]
+            mem = match[1].to_f * 1024
+          end
+
+          mem
+        end
+
+        def self.file_descriptor_count
+          Dir.glob('/proc/self/fd/*').length
+        end
+      else
+        def self.memory_usage
+          0.0
+        end
+
+        def self.file_descriptor_count
+          0
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/metrics/transaction.rb b/lib/gitlab/metrics/transaction.rb
new file mode 100644
index 00000000000..68b86de0655
--- /dev/null
+++ b/lib/gitlab/metrics/transaction.rb
@@ -0,0 +1,79 @@
+module Gitlab
+  module Metrics
+    # Class for storing metrics information of a single transaction.
+    class Transaction
+      THREAD_KEY = :_gitlab_metrics_transaction
+
+      attr_reader :uuid, :tags
+
+      def self.current
+        Thread.current[THREAD_KEY]
+      end
+
+      def initialize
+        @metrics = []
+        @uuid    = SecureRandom.uuid
+
+        @started_at  = nil
+        @finished_at = nil
+
+        @values = Hash.new(0)
+        @tags   = {}
+      end
+
+      def duration
+        @finished_at ? (@finished_at - @started_at) * 1000.0 : 0.0
+      end
+
+      def run
+        Thread.current[THREAD_KEY] = self
+
+        @started_at = Time.now
+
+        yield
+      ensure
+        @finished_at = Time.now
+
+        Thread.current[THREAD_KEY] = nil
+      end
+
+      def add_metric(series, values, tags = {})
+        tags   = tags.merge(transaction_id: @uuid)
+        prefix = sidekiq? ? 'sidekiq_' : 'rails_'
+
+        @metrics << Metric.new("#{prefix}#{series}", values, tags)
+      end
+
+      def increment(name, value)
+        @values[name] += value
+      end
+
+      def add_tag(key, value)
+        @tags[key] = value
+      end
+
+      def finish
+        track_self
+        submit
+      end
+
+      def track_self
+        values = { duration: duration }
+
+        @values.each do |name, value|
+          values[name] = value
+        end
+
+        add_metric('transactions', values, @tags)
+      end
+
+      def submit
+        Metrics.submit_metrics(@metrics.map(&:to_hash))
+      end
+
+      def sidekiq?
+        Sidekiq.server?
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/o_auth/auth_hash.rb b/lib/gitlab/o_auth/auth_hash.rb
index d94b104bbf8..ba31599432b 100644
--- a/lib/gitlab/o_auth/auth_hash.rb
+++ b/lib/gitlab/o_auth/auth_hash.rb
@@ -62,7 +62,7 @@ module Gitlab
       # Get the first part of the email address (before @)
       # In addtion in removes illegal characters
       def generate_username(email)
-        email.match(/^[^@]*/)[0].parameterize
+        email.match(/^[^@]*/)[0].mb_chars.normalize(:kd).gsub(/[^\x00-\x7F]/,'').to_s
       end
 
       def generate_temporarily_email(username)
diff --git a/lib/gitlab/o_auth/provider.rb b/lib/gitlab/o_auth/provider.rb
index 90c3fe8da33..9ad7a38d505 100644
--- a/lib/gitlab/o_auth/provider.rb
+++ b/lib/gitlab/o_auth/provider.rb
@@ -1,6 +1,12 @@
 module Gitlab
   module OAuth
     class Provider
+      LABELS = {
+        "github"         => "GitHub",
+        "gitlab"         => "GitLab.com",
+        "google_oauth2"  => "Google"
+      }.freeze
+
       def self.providers
         Devise.omniauth_providers
       end
@@ -23,8 +29,9 @@ module Gitlab
       end
 
       def self.label_for(name)
+        name = name.to_s
         config = config_for(name)
-        (config && config['label']) || name.to_s.titleize
+        (config && config['label']) || LABELS[name] || name.titleize
       end
     end
   end
diff --git a/lib/gitlab/o_auth/session.rb b/lib/gitlab/o_auth/session.rb
new file mode 100644
index 00000000000..f33bfd0bd0e
--- /dev/null
+++ b/lib/gitlab/o_auth/session.rb
@@ -0,0 +1,17 @@
+module Gitlab
+  module OAuth
+    module Session
+      def self.create(provider, ticket)
+        Rails.cache.write("gitlab:#{provider}:#{ticket}", ticket, expires_in: Gitlab.config.omniauth.cas3.session_duration)
+      end
+
+      def self.destroy(provider, ticket)
+        Rails.cache.delete("gitlab:#{provider}:#{ticket}")
+      end
+
+      def self.valid?(provider, ticket)
+        Rails.cache.read("gitlab:#{provider}:#{ticket}").present?
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/o_auth/user.rb b/lib/gitlab/o_auth/user.rb
index 17ce4d4b174..f1a362f5303 100644
--- a/lib/gitlab/o_auth/user.rb
+++ b/lib/gitlab/o_auth/user.rb
@@ -64,7 +64,7 @@ module Gitlab
 
         # If a corresponding person exists with same uid in a LDAP server,
         # set up a Gitlab user with dual LDAP and Omniauth identities.
-        if user = Gitlab::LDAP::User.find_by_uid_and_provider(ldap_person.dn.downcase, ldap_person.provider)
+        if user = Gitlab::LDAP::User.find_by_uid_and_provider(ldap_person.dn, ldap_person.provider)
           # Case when a LDAP user already exists in Gitlab. Add the Omniauth identity to existing account.
           user.identities.build(extern_uid: auth_hash.uid, provider: auth_hash.provider)
         else
diff --git a/lib/gitlab/project_search_results.rb b/lib/gitlab/project_search_results.rb
index 0dab7bcfa4d..70de6a74e76 100644
--- a/lib/gitlab/project_search_results.rb
+++ b/lib/gitlab/project_search_results.rb
@@ -9,7 +9,7 @@ module Gitlab
                         else
                           nil
                         end
-      @query = Shellwords.shellescape(query) if query.present?
+      @query = query
     end
 
     def objects(scope, page = nil)
@@ -20,6 +20,8 @@ module Gitlab
         Kaminari.paginate_array(blobs).page(page).per(per_page)
       when 'wiki_blobs'
         Kaminari.paginate_array(wiki_blobs).page(page).per(per_page)
+      when 'commits'
+        Kaminari.paginate_array(commits).page(page).per(per_page)
       else
         super
       end
@@ -27,7 +29,7 @@ module Gitlab
 
     def total_count
       @total_count ||= issues_count + merge_requests_count + blobs_count +
-                       notes_count + wiki_blobs_count
+                       notes_count + wiki_blobs_count + commits_count
     end
 
     def blobs_count
@@ -42,6 +44,10 @@ module Gitlab
       @wiki_blobs_count ||= wiki_blobs.count
     end
 
+    def commits_count
+      @commits_count ||= commits.count
+    end
+
     private
 
     def blobs
@@ -70,6 +76,14 @@ module Gitlab
       Note.where(project_id: limit_project_ids).user.search(query).order('updated_at DESC')
     end
 
+    def commits
+      if project.empty_repo? || query.blank?
+        []
+      else
+        project.repository.find_commits_by_message(query).compact
+      end
+    end
+
     def limit_project_ids
       [project.id]
     end
diff --git a/lib/gitlab/push_data_builder.rb b/lib/gitlab/push_data_builder.rb
index d010ade704e..4f9cdef3869 100644
--- a/lib/gitlab/push_data_builder.rb
+++ b/lib/gitlab/push_data_builder.rb
@@ -30,9 +30,12 @@ module Gitlab
 
         # For performance purposes maximum 20 latest commits
         # will be passed as post receive hook data.
-        commit_attrs = commits_limited.map(&:hook_attrs)
+        commit_attrs = commits_limited.map do |commit|
+          commit.hook_attrs(with_changed_files: true)
+        end
 
         type = Gitlab::Git.tag_ref?(ref) ? "tag_push" : "push"
+
         # Hash to be passed as post_receive_data
         data = {
           object_kind: type,
diff --git a/lib/gitlab/recaptcha.rb b/lib/gitlab/recaptcha.rb
new file mode 100644
index 00000000000..70e7f25d518
--- /dev/null
+++ b/lib/gitlab/recaptcha.rb
@@ -0,0 +1,14 @@
+module Gitlab
+  module Recaptcha
+    def self.load_configurations!
+      if current_application_settings.recaptcha_enabled
+        ::Recaptcha.configure do |config|
+          config.public_key  = current_application_settings.recaptcha_site_key
+          config.private_key = current_application_settings.recaptcha_private_key
+        end
+
+        true
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/reference_extractor.rb b/lib/gitlab/reference_extractor.rb
index da8df8a3025..be795649e59 100644
--- a/lib/gitlab/reference_extractor.rb
+++ b/lib/gitlab/reference_extractor.rb
@@ -1,73 +1,42 @@
-require 'gitlab/markdown'
+require 'banzai'
 
 module Gitlab
   # Extract possible GFM references from an arbitrary String for further processing.
-  class ReferenceExtractor
-    attr_accessor :project, :current_user, :load_lazy_references
+  class ReferenceExtractor < Banzai::ReferenceExtractor
+    attr_accessor :project, :current_user, :author
 
-    def initialize(project, current_user = nil, load_lazy_references: true)
+    def initialize(project, current_user = nil, author = nil)
       @project = project
       @current_user = current_user
-      @load_lazy_references = load_lazy_references
+      @author = author
+
+      @references = {}
+
+      super()
     end
 
-    def analyze(text)
-      references.clear
-      @text = Gitlab::Markdown.render_without_gfm(text)
+    def analyze(text, context = {})
+      super(text, context.merge(project: project))
     end
 
-    %i(user label issue merge_request snippet commit commit_range).each do |type|
+    %i(user label merge_request snippet commit commit_range).each do |type|
       define_method("#{type}s") do
-        references[type]
+        @references[type] ||= references(type, reference_context)
       end
     end
 
-    private
-
-    def references
-      @references ||= Hash.new do |references, type|
-        type = type.to_sym
-        next references[type] if references.has_key?(type)
-
-        references[type] = pipeline_result(type)
+    def issues
+      if project && project.jira_tracker?
+        @references[:external_issue] ||= references(:external_issue, reference_context)
+      else
+        @references[:issue] ||= references(:issue, reference_context)
       end
     end
 
-    # Instantiate and call HTML::Pipeline with a single reference filter type,
-    # returning the result
-    #
-    # filter_type - Symbol reference type (e.g., :commit, :issue, etc.)
-    #
-    # Returns the results Array for the requested filter type
-    def pipeline_result(filter_type)
-      return [] if @text.blank?
-      
-      klass  = "#{filter_type.to_s.camelize}ReferenceFilter"
-      filter = Gitlab::Markdown.const_get(klass)
-
-      context = {
-        project: project,
-        current_user: current_user,
-        
-        # We don't actually care about the links generated
-        only_path: true,
-        ignore_blockquotes: true,
-
-        # ReferenceGathererFilter
-        load_lazy_references: false,
-        reference_filter:     filter
-      }
-
-      pipeline = HTML::Pipeline.new([filter, Gitlab::Markdown::ReferenceGathererFilter], context)
-      result = pipeline.call(@text)
-
-      values = result[:references][filter_type].uniq
-
-      if @load_lazy_references
-        values = Gitlab::Markdown::ReferenceFilter::LazyReference.load(values).uniq
-      end
+    private
 
-      values
+    def reference_context
+      { project: project, current_user: current_user, author: author }
     end
   end
 end
diff --git a/lib/gitlab/regex.rb b/lib/gitlab/regex.rb
index 9f1adc860d1..53ab2686b43 100644
--- a/lib/gitlab/regex.rb
+++ b/lib/gitlab/regex.rb
@@ -51,6 +51,23 @@ module Gitlab
       "can contain only letters, digits, '_', '-' and '.'. "
     end
 
+    def file_path_regex
+      @file_path_regex ||= /\A[a-zA-Z0-9_\-\.\/]*\z/.freeze
+    end
+
+    def file_path_regex_message
+      "can contain only letters, digits, '_', '-' and '.'. Separate directories with a '/'. "
+    end
+
+
+    def directory_traversal_regex
+      @directory_traversal_regex ||= /\.{2}/.freeze
+    end
+
+    def directory_traversal_regex_message
+      "cannot include directory traversal. "
+    end
+
 
     def archive_formats_regex
       #                           |zip|tar|    tar.gz    |         tar.bz2         |
diff --git a/lib/gitlab/seeder.rb b/lib/gitlab/seeder.rb
index 31aa3528c4c..2ef0e982256 100644
--- a/lib/gitlab/seeder.rb
+++ b/lib/gitlab/seeder.rb
@@ -14,7 +14,7 @@ module Gitlab
 
     def self.mute_mailer
       code = <<-eos
-def Notify.delay
+def Notify.deliver_later
   self
 end
       eos
diff --git a/lib/gitlab/sherlock.rb b/lib/gitlab/sherlock.rb
new file mode 100644
index 00000000000..6360527a7aa
--- /dev/null
+++ b/lib/gitlab/sherlock.rb
@@ -0,0 +1,19 @@
+require 'securerandom'
+
+module Gitlab
+  module Sherlock
+    @collection = Collection.new
+
+    class << self
+      attr_reader :collection
+    end
+
+    def self.enabled?
+      Rails.env.development? && !!ENV['ENABLE_SHERLOCK']
+    end
+
+    def self.enable_line_profiler?
+      RUBY_ENGINE == 'ruby'
+    end
+  end
+end
diff --git a/lib/gitlab/sherlock/collection.rb b/lib/gitlab/sherlock/collection.rb
new file mode 100644
index 00000000000..66bd6258521
--- /dev/null
+++ b/lib/gitlab/sherlock/collection.rb
@@ -0,0 +1,49 @@
+module Gitlab
+  module Sherlock
+    # A collection of transactions recorded by Sherlock.
+    #
+    # Method calls for this class are synchronized using a mutex to allow
+    # sharing of a single Collection instance between threads (e.g. when using
+    # Puma as a webserver).
+    class Collection
+      include Enumerable
+
+      def initialize
+        @transactions = []
+        @mutex = Mutex.new
+      end
+
+      def add(transaction)
+        synchronize { @transactions << transaction }
+      end
+
+      alias_method :<<, :add
+
+      def each(&block)
+        synchronize { @transactions.each(&block) }
+      end
+
+      def clear
+        synchronize { @transactions.clear }
+      end
+
+      def empty?
+        synchronize { @transactions.empty? }
+      end
+
+      def find_transaction(id)
+        find { |trans| trans.id == id }
+      end
+
+      def newest_first
+        sort { |a, b| b.finished_at <=> a.finished_at }
+      end
+
+      private
+
+      def synchronize(&block)
+        @mutex.synchronize(&block)
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/sherlock/file_sample.rb b/lib/gitlab/sherlock/file_sample.rb
new file mode 100644
index 00000000000..8a3e1a5e5bf
--- /dev/null
+++ b/lib/gitlab/sherlock/file_sample.rb
@@ -0,0 +1,31 @@
+module Gitlab
+  module Sherlock
+    class FileSample
+      attr_reader :id, :file, :line_samples, :events, :duration
+
+      # file - The full path to the file this sample belongs to.
+      # line_samples - An array of LineSample objects.
+      # duration - The total execution time in milliseconds.
+      # events - The total amount of events.
+      def initialize(file, line_samples, duration, events)
+        @id = SecureRandom.uuid
+        @file = file
+        @line_samples = line_samples
+        @duration = duration
+        @events = events
+      end
+
+      def relative_path
+        @relative_path ||= @file.gsub(/^#{Rails.root.to_s}\/?/, '')
+      end
+
+      def to_param
+        @id
+      end
+
+      def source
+        @source ||= File.read(@file)
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/sherlock/line_profiler.rb b/lib/gitlab/sherlock/line_profiler.rb
new file mode 100644
index 00000000000..aa1468bff6b
--- /dev/null
+++ b/lib/gitlab/sherlock/line_profiler.rb
@@ -0,0 +1,98 @@
+module Gitlab
+  module Sherlock
+    # Class for profiling code on a per line basis.
+    #
+    # The LineProfiler class can be used to profile code on per line basis
+    # without littering your code with Ruby implementation specific profiling
+    # methods.
+    #
+    # This profiler only includes samples taking longer than a given threshold
+    # and those that occur in the actual application (e.g. files from Gems are
+    # ignored).
+    class LineProfiler
+      # The minimum amount of time that has to be spent in a file for it to be
+      # included in a list of samples.
+      MINIMUM_DURATION = 10.0
+
+      # Profiles the given block.
+      #
+      # Example:
+      #
+      #     profiler = LineProfiler.new
+      #
+      #     retval, samples = profiler.profile do
+      #       "cats are amazing"
+      #     end
+      #
+      #     retval  # => "cats are amazing"
+      #     samples # => [#<Gitlab::Sherlock::FileSample ...>, ...]
+      #
+      # Returns an Array containing the block's return value and an Array of
+      # FileSample objects.
+      def profile(&block)
+        if mri?
+          profile_mri(&block)
+        else
+          raise NotImplementedError,
+            'Line profiling is not supported on this platform'
+        end
+      end
+
+      # Profiles the given block using rblineprof (MRI only).
+      def profile_mri
+        require 'rblineprof'
+
+        retval  = nil
+        samples = lineprof(/^#{Rails.root.to_s}/) { retval = yield }
+
+        file_samples = aggregate_rblineprof(samples)
+
+        [retval, file_samples]
+      end
+
+      # Returns an Array of file samples based on the output of rblineprof.
+      #
+      # lineprof_stats - A Hash containing rblineprof statistics on a per file
+      #                  basis.
+      #
+      # Returns an Array of FileSample objects.
+      def aggregate_rblineprof(lineprof_stats)
+        samples = []
+
+        lineprof_stats.each do |(file, stats)|
+          source_lines = File.read(file).each_line.to_a
+          line_samples = []
+
+          total_duration = microsec_to_millisec(stats[0][0])
+          total_events   = stats[0][2]
+
+          next if total_duration <= MINIMUM_DURATION
+
+          stats[1..-1].each_with_index do |data, index|
+            next unless source_lines[index]
+
+            duration = microsec_to_millisec(data[0])
+            events   = data[2]
+
+            line_samples << LineSample.new(duration, events)
+          end
+
+          samples << FileSample.
+            new(file, line_samples, total_duration, total_events)
+        end
+
+        samples
+      end
+
+      private
+
+      def microsec_to_millisec(microsec)
+        microsec / 1000.0
+      end
+
+      def mri?
+        RUBY_ENGINE == 'ruby'
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/sherlock/line_sample.rb b/lib/gitlab/sherlock/line_sample.rb
new file mode 100644
index 00000000000..eb1948eb6d6
--- /dev/null
+++ b/lib/gitlab/sherlock/line_sample.rb
@@ -0,0 +1,36 @@
+module Gitlab
+  module Sherlock
+    class LineSample
+      attr_reader :duration, :events
+
+      # duration - The execution time in milliseconds.
+      # events - The amount of events.
+      def initialize(duration, events)
+        @duration = duration
+        @events = events
+      end
+
+      # Returns the sample duration percentage relative to the given duration.
+      #
+      # Example:
+      #
+      #     sample.duration            # => 150
+      #     sample.percentage_of(1500) # => 10.0
+      #
+      # total_duration - The total duration to compare with.
+      #
+      # Returns a float
+      def percentage_of(total_duration)
+        (duration.to_f / total_duration) * 100.0
+      end
+
+      # Returns true if the current sample takes up the majority of the given
+      # duration.
+      #
+      # total_duration - The total duration to compare with.
+      def majority_of?(total_duration)
+        percentage_of(total_duration) >= 30
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/sherlock/location.rb b/lib/gitlab/sherlock/location.rb
new file mode 100644
index 00000000000..5ac265618ad
--- /dev/null
+++ b/lib/gitlab/sherlock/location.rb
@@ -0,0 +1,26 @@
+module Gitlab
+  module Sherlock
+    class Location
+      attr_reader :path, :line
+
+      SHERLOCK_DIR = File.dirname(__FILE__)
+
+      # Creates a new Location from a `Thread::Backtrace::Location`.
+      def self.from_ruby_location(location)
+        new(location.path, location.lineno)
+      end
+
+      # path - The full path of the frame as a String.
+      # line - The line number of the frame as a Fixnum.
+      def initialize(path, line)
+        @path = path
+        @line = line
+      end
+
+      # Returns true if the current frame originated from the application.
+      def application?
+        @path.start_with?(Rails.root.to_s) && !path.start_with?(SHERLOCK_DIR)
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/sherlock/middleware.rb b/lib/gitlab/sherlock/middleware.rb
new file mode 100644
index 00000000000..687332fc5fc
--- /dev/null
+++ b/lib/gitlab/sherlock/middleware.rb
@@ -0,0 +1,41 @@
+module Gitlab
+  module Sherlock
+    # Rack middleware used for tracking request metrics.
+    class Middleware
+      CONTENT_TYPES = /text\/html|application\/json/i
+
+      IGNORE_PATHS = %r{^/sherlock}
+
+      def initialize(app)
+        @app = app
+      end
+
+      # env - A Hash containing Rack environment details.
+      def call(env)
+        if instrument?(env)
+          call_with_instrumentation(env)
+        else
+          @app.call(env)
+        end
+      end
+
+      def call_with_instrumentation(env)
+        trans = transaction_from_env(env)
+        retval = trans.run { @app.call(env) }
+
+        Sherlock.collection.add(trans)
+
+        retval
+      end
+
+      def instrument?(env)
+        !!(env['HTTP_ACCEPT'] =~ CONTENT_TYPES &&
+           env['REQUEST_URI'] !~ IGNORE_PATHS)
+      end
+
+      def transaction_from_env(env)
+        Transaction.new(env['REQUEST_METHOD'], env['REQUEST_URI'])
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/sherlock/query.rb b/lib/gitlab/sherlock/query.rb
new file mode 100644
index 00000000000..4917c4ae2ac
--- /dev/null
+++ b/lib/gitlab/sherlock/query.rb
@@ -0,0 +1,114 @@
+module Gitlab
+  module Sherlock
+    class Query
+      attr_reader :id, :query, :started_at, :finished_at, :backtrace
+
+      # SQL identifiers that should be prefixed with newlines.
+      PREFIX_NEWLINE = /
+        \s+(FROM
+          |(LEFT|RIGHT)?INNER\s+JOIN
+          |(LEFT|RIGHT)?OUTER\s+JOIN
+          |WHERE
+          |AND
+          |GROUP\s+BY
+          |ORDER\s+BY
+          |LIMIT
+          |OFFSET)\s+/ix # Vim indent breaks when this is on a newline :<
+
+      # Creates a new Query using a String and a separate Array of bindings.
+      #
+      # query - A String containing a SQL query, optionally with numeric
+      #         placeholders (`$1`, `$2`, etc).
+      #
+      # bindings - An Array of ActiveRecord columns and their values.
+      # started_at - The start time of the query as a Time-like object.
+      # finished_at - The completion time of the query as a Time-like object.
+      #
+      # Returns a new Query object.
+      def self.new_with_bindings(query, bindings, started_at, finished_at)
+        bindings.each_with_index do |(_, value), index|
+          quoted_value = ActiveRecord::Base.connection.quote(value)
+
+          query = query.gsub("$#{index + 1}", quoted_value)
+        end
+
+        new(query, started_at, finished_at)
+      end
+
+      # query - The SQL query as a String (without placeholders).
+      # started_at - The start time of the query as a Time-like object.
+      # finished_at - The completion time of the query as a Time-like object.
+      def initialize(query, started_at, finished_at)
+        @id = SecureRandom.uuid
+        @query = query
+        @started_at = started_at
+        @finished_at = finished_at
+        @backtrace = caller_locations.map do |loc|
+          Location.from_ruby_location(loc)
+        end
+
+        unless @query.end_with?(';')
+          @query += ';'
+        end
+      end
+
+      # Returns the query duration in milliseconds.
+      def duration
+        @duration ||= (@finished_at - @started_at) * 1000.0
+      end
+
+      def to_param
+        @id
+      end
+
+      # Returns a human readable version of the query.
+      def formatted_query
+        @formatted_query ||= format_sql(@query)
+      end
+
+      # Returns the last application frame of the backtrace.
+      def last_application_frame
+        @last_application_frame ||= @backtrace.find(&:application?)
+      end
+
+      # Returns an Array of application frames (excluding Gems and the likes).
+      def application_backtrace
+        @application_backtrace ||= @backtrace.select(&:application?)
+      end
+
+      # Returns the query plan as a String.
+      def explain
+        unless @explain
+          ActiveRecord::Base.connection.transaction do
+            @explain = raw_explain(@query).values.flatten.join("\n")
+
+            # Roll back any queries that mutate data so we don't mess up
+            # anything when running explain on an INSERT, UPDATE, DELETE, etc.
+            raise ActiveRecord::Rollback
+          end
+        end
+
+        @explain
+      end
+
+      private
+
+      def raw_explain(query)
+        if Gitlab::Database.postgresql?
+          explain = "EXPLAIN ANALYZE #{query};"
+        else
+          explain = "EXPLAIN #{query};"
+        end
+
+        ActiveRecord::Base.connection.execute(explain)
+      end
+
+      def format_sql(query)
+        query.each_line.
+          map { |line| line.strip }.
+          join("\n").
+          gsub(PREFIX_NEWLINE) { "\n#{$1} " }
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/sherlock/transaction.rb b/lib/gitlab/sherlock/transaction.rb
new file mode 100644
index 00000000000..3489fb251b6
--- /dev/null
+++ b/lib/gitlab/sherlock/transaction.rb
@@ -0,0 +1,136 @@
+module Gitlab
+  module Sherlock
+    class Transaction
+      attr_reader :id, :type, :path, :queries, :file_samples, :started_at,
+        :finished_at, :view_counts
+
+      # type - The type of transaction (e.g. "GET", "POST", etc)
+      # path - The path of the transaction (e.g. the HTTP request path)
+      def initialize(type, path)
+        @id = SecureRandom.uuid
+        @type = type
+        @path = path
+        @queries = []
+        @file_samples = []
+        @started_at = nil
+        @finished_at = nil
+        @thread = Thread.current
+        @view_counts = Hash.new(0)
+      end
+
+      # Runs the transaction and returns the block's return value.
+      def run
+        @started_at = Time.now
+
+        retval = with_subscriptions do
+          profile_lines { yield }
+        end
+
+        @finished_at = Time.now
+
+        retval
+      end
+
+      # Returns the duration in seconds.
+      def duration
+        @duration ||= started_at && finished_at ? finished_at - started_at : 0
+      end
+
+      # Returns the total query duration in seconds.
+      def query_duration
+        @query_duration ||= @queries.map { |q| q.duration }.inject(:+) / 1000.0
+      end
+
+      def to_param
+        @id
+      end
+
+      # Returns the queries sorted in descending order by their durations.
+      def sorted_queries
+        @queries.sort { |a, b| b.duration <=> a.duration }
+      end
+
+      # Returns the file samples sorted in descending order by their durations.
+      def sorted_file_samples
+        @file_samples.sort { |a, b| b.duration <=> a.duration }
+      end
+
+      # Finds a query by the given ID.
+      #
+      # id - The query ID as a String.
+      #
+      # Returns a Query object if one could be found, nil otherwise.
+      def find_query(id)
+        @queries.find { |query| query.id == id }
+      end
+
+      # Finds a file sample by the given ID.
+      #
+      # id - The query ID as a String.
+      #
+      # Returns a FileSample object if one could be found, nil otherwise.
+      def find_file_sample(id)
+        @file_samples.find { |sample| sample.id == id }
+      end
+
+      def profile_lines
+        retval = nil
+
+        if Sherlock.enable_line_profiler?
+          retval, @file_samples = LineProfiler.new.profile { yield }
+        else
+          retval = yield
+        end
+
+        retval
+      end
+
+      def subscribe_to_active_record
+        ActiveSupport::Notifications.subscribe('sql.active_record') do |_, start, finish, _, data|
+          next unless same_thread?
+
+          track_query(data[:sql].strip, data[:binds], start, finish)
+        end
+      end
+
+      def subscribe_to_action_view
+        regex = /render_(template|partial)\.action_view/
+
+        ActiveSupport::Notifications.subscribe(regex) do |_, start, finish, _, data|
+          next unless same_thread?
+
+          track_view(data[:identifier])
+        end
+      end
+
+      private
+
+      def track_query(query, bindings, start, finish)
+        @queries << Query.new_with_bindings(query, bindings, start, finish)
+      end
+
+      def track_view(path)
+        @view_counts[path] += 1
+      end
+
+      def with_subscriptions
+        ar_subscriber = subscribe_to_active_record
+        av_subscriber = subscribe_to_action_view
+
+        retval = yield
+
+        ActiveSupport::Notifications.unsubscribe(ar_subscriber)
+        ActiveSupport::Notifications.unsubscribe(av_subscriber)
+
+        retval
+      end
+
+      # In case somebody uses a multi-threaded server locally (e.g. Puma) we
+      # _only_ want to track notifications that originate from the transaction
+      # thread.
+      def same_thread?
+        Thread.current == @thread
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/sql/union.rb b/lib/gitlab/sql/union.rb
new file mode 100644
index 00000000000..1cd89b3a9c4
--- /dev/null
+++ b/lib/gitlab/sql/union.rb
@@ -0,0 +1,34 @@
+module Gitlab
+  module SQL
+    # Class for building SQL UNION statements.
+    #
+    # ORDER BYs are dropped from the relations as the final sort order is not
+    # guaranteed any way.
+    #
+    # Example usage:
+    #
+    #     union = Gitlab::SQL::Union.new(user.personal_projects, user.projects)
+    #     sql   = union.to_sql
+    #
+    #     Project.where("id IN (#{sql})")
+    class Union
+      def initialize(relations)
+        @relations = relations
+      end
+
+      def to_sql
+        # Some relations may include placeholders for prepared statements, these
+        # aren't incremented properly when joining relations together this way.
+        # By using "unprepared_statements" we remove the usage of placeholders
+        # (thus fixing this problem), at a slight performance cost.
+        fragments = ActiveRecord::Base.connection.unprepared_statement do
+          @relations.map do |rel|
+            rel.reorder(nil).to_sql
+          end
+        end
+
+        fragments.join("\nUNION\n")
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/upgrader.rb b/lib/gitlab/upgrader.rb
index cf040971c6e..f3567f3ef85 100644
--- a/lib/gitlab/upgrader.rb
+++ b/lib/gitlab/upgrader.rb
@@ -50,15 +50,15 @@ module Gitlab
     end
 
     def fetch_git_tags
-      remote_tags, _ = Gitlab::Popen.popen(%W(git ls-remote --tags https://gitlab.com/gitlab-org/gitlab-ce.git))
+      remote_tags, _ = Gitlab::Popen.popen(%W(#{Gitlab.config.git.bin_path} ls-remote --tags https://gitlab.com/gitlab-org/gitlab-ce.git))
       remote_tags.split("\n").grep(/tags\/v#{current_version.major}/)
     end
 
     def update_commands
       {
-        "Stash changed files" => %W(git stash),
-        "Get latest code" => %W(git fetch),
-        "Switch to new version" => %W(git checkout v#{latest_version}),
+        "Stash changed files" => %W(#{Gitlab.config.git.bin_path} stash),
+        "Get latest code" => %W(#{Gitlab.config.git.bin_path} fetch),
+        "Switch to new version" => %W(#{Gitlab.config.git.bin_path} checkout v#{latest_version}),
         "Install gems" => %W(bundle),
         "Migrate DB" => %W(bundle exec rake db:migrate),
         "Recompile assets" => %W(bundle exec rake assets:clean assets:precompile),
diff --git a/lib/gitlab/visibility_level.rb b/lib/gitlab/visibility_level.rb
index 335dc44be19..3160a3c7582 100644
--- a/lib/gitlab/visibility_level.rb
+++ b/lib/gitlab/visibility_level.rb
@@ -51,6 +51,15 @@ module Gitlab
       def allowed_fork_levels(origin_level)
         [PRIVATE, INTERNAL, PUBLIC].select{ |level| level <= origin_level }
       end
+
+      def level_name(level)
+        level_name = 'Unknown'
+        options.each do |name, lvl|
+          level_name = name if lvl == level.to_i
+        end
+
+        level_name
+      end
     end
 
     def private?