Merge branch 'master' into zj-create-mattermost-team

89 files changed, 1580 insertions, 475 deletions

diff --git a/lib/api/api.rb b/lib/api/api.rb
index 1803387bb8c..b27ac3f1d15 100644
--- a/lib/api/api.rb
+++ b/lib/api/api.rb
@@ -5,11 +5,15 @@ module API
     version %w(v3 v4), using: :path
 
     version 'v3', using: :path do
+      mount ::API::V3::AwardEmoji
       mount ::API::V3::Boards
       mount ::API::V3::Branches
+      mount ::API::V3::BroadcastMessages
       mount ::API::V3::Commits
       mount ::API::V3::DeployKeys
+      mount ::API::V3::Environments
       mount ::API::V3::Files
+      mount ::API::V3::Groups
       mount ::API::V3::Issues
       mount ::API::V3::Labels
       mount ::API::V3::Members
@@ -20,12 +24,16 @@ module API
       mount ::API::V3::Projects
       mount ::API::V3::ProjectSnippets
       mount ::API::V3::Repositories
+      mount ::API::V3::Runners
+      mount ::API::V3::Services
       mount ::API::V3::Subscriptions
       mount ::API::V3::SystemHooks
       mount ::API::V3::Tags
-      mount ::API::V3::Todos
       mount ::API::V3::Templates
+      mount ::API::V3::Todos
+      mount ::API::V3::Triggers
       mount ::API::V3::Users
+      mount ::API::V3::Variables
     end
 
     before { allow_access_with_scope :api }
@@ -90,6 +98,7 @@ module API
     mount ::API::Projects
     mount ::API::ProjectSnippets
     mount ::API::Repositories
+    mount ::API::Runner
     mount ::API::Runners
     mount ::API::Services
     mount ::API::Session
diff --git a/lib/api/api_guard.rb b/lib/api/api_guard.rb
index c11f8529183..409cb5b924f 100644
--- a/lib/api/api_guard.rb
+++ b/lib/api/api_guard.rb
@@ -160,13 +160,10 @@ module API
     # Exceptions
     #
 
-    class MissingTokenError < StandardError; end
-
-    class TokenNotFoundError < StandardError; end
-
-    class ExpiredError < StandardError; end
-
-    class RevokedError < StandardError; end
+    MissingTokenError = Class.new(StandardError)
+    TokenNotFoundError = Class.new(StandardError)
+    ExpiredError = Class.new(StandardError)
+    RevokedError = Class.new(StandardError)
 
     class InsufficientScopeError < StandardError
       attr_reader :scopes
diff --git a/lib/api/award_emoji.rb b/lib/api/award_emoji.rb
index 301271118d4..07a1bcdbe18 100644
--- a/lib/api/award_emoji.rb
+++ b/lib/api/award_emoji.rb
@@ -83,7 +83,6 @@ module API
             unauthorized! unless award.user == current_user || current_user.admin?
 
             award.destroy
-            present award, with: Entities::AwardEmoji
           end
         end
       end
diff --git a/lib/api/boards.rb b/lib/api/boards.rb
index f4226e5a89d..b6843c1b6af 100644
--- a/lib/api/boards.rb
+++ b/lib/api/boards.rb
@@ -127,9 +127,7 @@ module API
 
           service = ::Boards::Lists::DestroyService.new(user_project, current_user)
 
-          if service.execute(list)
-            present list, with: Entities::List
-          else
+          unless service.execute(list)
             render_api_error!({ error: 'List could not be deleted!' }, 400)
           end
         end
diff --git a/lib/api/branches.rb b/lib/api/branches.rb
index c65de90cca2..73a7e939627 100644
--- a/lib/api/branches.rb
+++ b/lib/api/branches.rb
@@ -124,11 +124,7 @@ module API
         result = DeleteBranchService.new(user_project, current_user).
                  execute(params[:branch])
 
-        if result[:status] == :success
-          {
-            branch: params[:branch]
-          }
-        else
+        if result[:status] != :success
           render_api_error!(result[:message], result[:return_code])
         end
       end
@@ -137,7 +133,7 @@ module API
       delete ":id/repository/merged_branches" do
         DeleteMergedBranchesService.new(user_project, current_user).async_execute
 
-        status(200)
+        accepted!
       end
     end
   end
diff --git a/lib/api/broadcast_messages.rb b/lib/api/broadcast_messages.rb
index 1217002bf8e..395c401203c 100644
--- a/lib/api/broadcast_messages.rb
+++ b/lib/api/broadcast_messages.rb
@@ -91,7 +91,7 @@ module API
       delete ':id' do
         message = find_message
 
-        present message.destroy, with: Entities::BroadcastMessage
+        message.destroy
       end
     end
   end
diff --git a/lib/api/commits.rb b/lib/api/commits.rb
index 9ce396d4660..fd03e92264d 100644
--- a/lib/api/commits.rb
+++ b/lib/api/commits.rb
@@ -52,13 +52,6 @@ module API
 
         attrs = declared_params.merge(start_branch: declared_params[:branch], target_branch: declared_params[:branch])
 
-        attrs[:actions].map! do |action|
-          action[:action] = action[:action].to_sym
-          action[:file_path].slice!(0) if action[:file_path] && action[:file_path].start_with?('/')
-          action[:previous_path].slice!(0) if action[:previous_path] && action[:previous_path].start_with?('/')
-          action
-        end
-
         result = ::Files::MultiService.new(user_project, current_user, attrs).execute
 
         if result[:status] == :success
diff --git a/lib/api/entities.rb b/lib/api/entities.rb
index 85aa6932f81..9dccaff369e 100644
--- a/lib/api/entities.rb
+++ b/lib/api/entities.rb
@@ -98,7 +98,7 @@ module API
       expose :shared_with_groups do |project, options|
         SharedGroup.represent(project.project_group_links.all, options)
       end
-      expose :only_allow_merge_if_build_succeeds
+      expose :only_allow_merge_if_pipeline_succeeds
       expose :request_access_enabled
       expose :only_allow_merge_if_all_discussions_are_resolved
 
@@ -288,7 +288,7 @@ module API
       expose :label_names, as: :labels
       expose :work_in_progress?, as: :work_in_progress
       expose :milestone, using: Entities::Milestone
-      expose :merge_when_build_succeeds
+      expose :merge_when_pipeline_succeeds
       expose :merge_status
       expose :diff_head_sha, as: :sha
       expose :merge_commit_sha
@@ -394,7 +394,8 @@ module API
       expose :target_type
 
       expose :target do |todo, options|
-        Entities.const_get(todo.target_type).represent(todo.target, options)
+        target = todo.target_type == 'Commit' ? 'RepoCommit' : todo.target_type
+        Entities.const_get(target).represent(todo.target, options)
       end
 
       expose :target_url do |todo, options|
@@ -557,6 +558,7 @@ module API
       expose :default_project_visibility
       expose :default_snippet_visibility
       expose :default_group_visibility
+      expose :default_artifacts_expire_in
       expose :domain_whitelist
       expose :domain_blacklist_enabled
       expose :domain_blacklist
@@ -617,6 +619,10 @@ module API
       end
     end
 
+    class RunnerRegistrationDetails < Grape::Entity
+      expose :id, :token
+    end
+
     class BuildArtifactFile < Grape::Entity
       expose :filename, :size
     end
diff --git a/lib/api/environments.rb b/lib/api/environments.rb
index 1a7e68f0528..ebe8c3a5b2c 100644
--- a/lib/api/environments.rb
+++ b/lib/api/environments.rb
@@ -79,7 +79,24 @@ module API
 
         environment = user_project.environments.find(params[:environment_id])
 
-        present environment.destroy, with: Entities::Environment
+        environment.destroy
+      end
+
+      desc 'Stops an existing environment' do
+        success Entities::Environment
+      end
+      params do
+        requires :environment_id, type: Integer,  desc: 'The environment ID'
+      end
+      post ':id/environments/:environment_id/stop' do
+        authorize! :create_deployment, user_project
+
+        environment = user_project.environments.find(params[:environment_id])
+
+        environment.stop_with_action!(current_user)
+
+        status 200
+        present environment, with: Entities::Environment
       end
     end
   end
diff --git a/lib/api/files.rb b/lib/api/files.rb
index 500f9d3c787..9c4e43d77cc 100644
--- a/lib/api/files.rb
+++ b/lib/api/files.rb
@@ -118,10 +118,7 @@ module API
         file_params = declared_params(include_missing: false)
         result = ::Files::DestroyService.new(user_project, current_user, commit_params(file_params)).execute
 
-        if result[:status] == :success
-          status(200)
-          commit_response(file_params)
-        else
+        if result[:status] != :success
           render_api_error!(result[:message], 400)
         end
       end
diff --git a/lib/api/groups.rb b/lib/api/groups.rb
index 9f29c4466ab..9cffd6180ae 100644
--- a/lib/api/groups.rb
+++ b/lib/api/groups.rb
@@ -36,12 +36,15 @@ module API
         optional :skip_groups, type: Array[Integer], desc: 'Array of group ids to exclude from list'
         optional :all_available, type: Boolean, desc: 'Show all group that you have access to'
         optional :search, type: String, desc: 'Search for a specific group'
+        optional :owned, type: Boolean, default: false, desc: 'Limit by owned by authenticated user'
         optional :order_by, type: String, values: %w[name path], default: 'name', desc: 'Order by name or path'
         optional :sort, type: String, values: %w[asc desc], default: 'asc', desc: 'Sort by asc (ascending) or desc (descending)'
         use :pagination
       end
       get do
-        groups = if current_user.admin
+        groups = if params[:owned]
+                   current_user.owned_groups
+                 elsif current_user.admin
                    Group.all
                  elsif params[:all_available]
                    GroupsFinder.new.execute(current_user)
@@ -56,17 +59,6 @@ module API
         present_groups groups, statistics: params[:statistics] && current_user.is_admin?
       end
 
-      desc 'Get list of owned groups for authenticated user' do
-        success Entities::Group
-      end
-      params do
-        use :pagination
-        use :statistics_params
-      end
-      get '/owned' do
-        present_groups current_user.owned_groups, statistics: params[:statistics]
-      end
-
       desc 'Create a group. Available only for users who can create groups.' do
         success Entities::Group
       end
diff --git a/lib/api/helpers.rb b/lib/api/helpers.rb
index d0efa7b993b..72d2b320077 100644
--- a/lib/api/helpers.rb
+++ b/lib/api/helpers.rb
@@ -209,6 +209,10 @@ module API
       render_api_error!('204 No Content', 204)
     end
 
+    def accepted!
+      render_api_error!('202 Accepted', 202)
+    end
+
     def render_validation_error!(model)
       if model.errors.any?
         render_api_error!(model.errors.messages || '400 Bad Request', 400)
diff --git a/lib/api/helpers/runner.rb b/lib/api/helpers/runner.rb
new file mode 100644
index 00000000000..119ca81b883
--- /dev/null
+++ b/lib/api/helpers/runner.rb
@@ -0,0 +1,23 @@
+module API
+  module Helpers
+    module Runner
+      def runner_registration_token_valid?
+        ActiveSupport::SecurityUtils.variable_size_secure_compare(params[:token],
+                                                                  current_application_settings.runners_registration_token)
+      end
+
+      def get_runner_version_from_params
+        return unless params['info'].present?
+        attributes_for_keys(%w(name version revision platform architecture), params['info'])
+      end
+
+      def authenticate_runner!
+        forbidden! unless current_runner
+      end
+
+      def current_runner
+        @runner ||= ::Ci::Runner.find_by_token(params[:token].to_s)
+      end
+    end
+  end
+end
diff --git a/lib/api/internal.rb b/lib/api/internal.rb
index d235977fbd8..7eed93aba00 100644
--- a/lib/api/internal.rb
+++ b/lib/api/internal.rb
@@ -132,6 +132,18 @@ module API
 
         { success: true, recovery_codes: codes }
       end
+
+      post "/notify_post_receive" do
+        status 200
+
+        return unless Gitlab::GitalyClient.enabled?
+
+        begin
+          Gitlab::GitalyClient::Notifications.new.post_receive(params[:repo_path])
+        rescue GRPC::Unavailable => e
+          render_api_error(e, 500)
+        end
+      end
     end
   end
 end
diff --git a/lib/api/labels.rb b/lib/api/labels.rb
index d2955af3f95..59f0e7cb647 100644
--- a/lib/api/labels.rb
+++ b/lib/api/labels.rb
@@ -1,7 +1,7 @@
 module API
   class Labels < Grape::API
     include PaginationParams
-    
+
     before { authenticate! }
 
     params do
@@ -56,7 +56,7 @@ module API
         label = user_project.labels.find_by(title: params[:name])
         not_found!('Label') unless label
 
-        present label.destroy, with: Entities::Label, current_user: current_user, project: user_project
+        label.destroy
       end
 
       desc 'Update an existing label. At least one optional parameter is required.' do
diff --git a/lib/api/members.rb b/lib/api/members.rb
index 8360c007005..baf85e6075a 100644
--- a/lib/api/members.rb
+++ b/lib/api/members.rb
@@ -55,7 +55,6 @@ module API
           authorize_admin_source!(source_type, source)
 
           member = source.members.find_by(user_id: params[:user_id])
-
           conflict!('Member already exists') if member
 
           member = source.add_user(params[:user_id], params[:access_level], current_user: current_user, expires_at: params[:expires_at])
@@ -63,9 +62,6 @@ module API
           if member.persisted? && member.valid?
             present member.user, with: Entities::Member, member: member
           else
-            # This is to ensure back-compatibility but 400 behavior should be used
-            # for all validation errors in 9.0!
-            render_api_error!('Access level is not known', 422) if member.errors.key?(:access_level)
             render_validation_error!(member)
           end
         end
@@ -87,9 +83,6 @@ module API
           if member.update_attributes(declared_params(include_missing: false))
             present member.user, with: Entities::Member, member: member
           else
-            # This is to ensure back-compatibility but 400 behavior should be used
-            # for all validation errors in 9.0!
-            render_api_error!('Access level is not known', 422) if member.errors.key?(:access_level)
             render_validation_error!(member)
           end
         end
@@ -100,24 +93,10 @@ module API
         end
         delete ":id/members/:user_id" do
           source = find_source(source_type, params[:id])
+          # Ensure that memeber exists
+          source.members.find_by!(user_id: params[:user_id])
 
-          # This is to ensure back-compatibility but find_by! should be used
-          # in that casse in 9.0!
-          member = source.members.find_by(user_id: params[:user_id])
-
-          # This is to ensure back-compatibility but this should be removed in
-          # favor of find_by! in 9.0!
-          not_found!("Member: user_id:#{params[:user_id]}") if source_type == 'group' && member.nil?
-
-          # This is to ensure back-compatibility but 204 behavior should be used
-          # for all DELETE endpoints in 9.0!
-          if member.nil?
-            { message: "Access revoked", id: params[:user_id].to_i }
-          else
-            ::Members::DestroyService.new(source, current_user, declared_params).execute
-
-            present member.user, with: Entities::Member, member: member
-          end
+          ::Members::DestroyService.new(source, current_user, declared_params).execute
         end
       end
     end
diff --git a/lib/api/merge_requests.rb b/lib/api/merge_requests.rb
index bdd764abfeb..4638a66811d 100644
--- a/lib/api/merge_requests.rb
+++ b/lib/api/merge_requests.rb
@@ -168,8 +168,8 @@ module API
         optional :merge_commit_message, type: String, desc: 'Custom merge commit message'
         optional :should_remove_source_branch, type: Boolean,
                                                desc: 'When true, the source branch will be deleted if possible'
-        optional :merge_when_build_succeeds, type: Boolean,
-                                             desc: 'When true, this merge request will be merged when the pipeline succeeds'
+        optional :merge_when_pipeline_succeeds, type: Boolean,
+                                                desc: 'When true, this merge request will be merged when the pipeline succeeds'
         optional :sha, type: String, desc: 'When present, must have the HEAD SHA of the source branch'
       end
       put ':id/merge_requests/:merge_request_id/merge' do
@@ -192,7 +192,7 @@ module API
           should_remove_source_branch: params[:should_remove_source_branch]
         }
 
-        if params[:merge_when_build_succeeds] && merge_request.head_pipeline && merge_request.head_pipeline.active?
+        if params[:merge_when_pipeline_succeeds] && merge_request.head_pipeline && merge_request.head_pipeline.active?
           ::MergeRequests::MergeWhenPipelineSucceedsService
             .new(merge_request.target_project, current_user, merge_params)
             .execute(merge_request)
@@ -208,10 +208,10 @@ module API
       desc 'Cancel merge if "Merge When Pipeline Succeeds" is enabled' do
         success Entities::MergeRequest
       end
-      post ':id/merge_requests/:merge_request_id/cancel_merge_when_build_succeeds' do
+      post ':id/merge_requests/:merge_request_id/cancel_merge_when_pipeline_succeeds' do
         merge_request = find_project_merge_request(params[:merge_request_id])
 
-        unauthorized! unless merge_request.can_cancel_merge_when_build_succeeds?(current_user)
+        unauthorized! unless merge_request.can_cancel_merge_when_pipeline_succeeds?(current_user)
 
         ::MergeRequest::MergeWhenPipelineSucceedsService
           .new(merge_request.target_project, current_user)
diff --git a/lib/api/notes.rb b/lib/api/notes.rb
index f559a7f74a0..3b3e45cbd06 100644
--- a/lib/api/notes.rb
+++ b/lib/api/notes.rb
@@ -132,8 +132,6 @@ module API
           authorize! :admin_note, note
 
           ::Notes::DestroyService.new(user_project, current_user).execute(note)
-
-          present note, with: Entities::Note
         end
       end
     end
diff --git a/lib/api/project_hooks.rb b/lib/api/project_hooks.rb
index f7a28d7ad10..57a5f97dc7f 100644
--- a/lib/api/project_hooks.rb
+++ b/lib/api/project_hooks.rb
@@ -90,12 +90,9 @@ module API
         requires :hook_id, type: Integer, desc: 'The ID of the hook to delete'
       end
       delete ":id/hooks/:hook_id" do
-        begin
-          present user_project.hooks.destroy(params[:hook_id]), with: Entities::ProjectHook
-        rescue
-          # ProjectHook can raise Error if hook_id not found
-          not_found!("Error deleting hook #{params[:hook_id]}")
-        end
+        hook = user_project.hooks.find(params.delete(:hook_id))
+
+        hook.destroy
       end
     end
   end
diff --git a/lib/api/projects.rb b/lib/api/projects.rb
index e7b891bd92e..996404e0e49 100644
--- a/lib/api/projects.rb
+++ b/lib/api/projects.rb
@@ -23,7 +23,7 @@ module API
         ], desc: 'Create a public project. The same as visibility_level = 20.'
         optional :public_builds, type: Boolean, desc: 'Perform public builds'
         optional :request_access_enabled, type: Boolean, desc: 'Allow users to request member access'
-        optional :only_allow_merge_if_build_succeeds, type: Boolean, desc: 'Only allow to merge if builds succeed'
+        optional :only_allow_merge_if_pipeline_succeeds, type: Boolean, desc: 'Only allow to merge if builds succeed'
         optional :only_allow_merge_if_all_discussions_are_resolved, type: Boolean, desc: 'Only allow to merge if all discussions are resolved'
       end
     end
@@ -94,8 +94,9 @@ module API
         success Entities::Project
       end
       params do
-        requires :name, type: String, desc: 'The name of the project'
+        optional :name, type: String, desc: 'The name of the project'
         optional :path, type: String, desc: 'The path of the repository'
+        at_least_one_of :name, :path
         use :optional_params
         use :create_params
       end
@@ -208,7 +209,7 @@ module API
                         :wiki_enabled, :builds_enabled, :snippets_enabled,
                         :shared_runners_enabled, :container_registry_enabled,
                         :lfs_enabled, :visibility_level, :public_builds,
-                        :request_access_enabled, :only_allow_merge_if_build_succeeds,
+                        :request_access_enabled, :only_allow_merge_if_pipeline_succeeds,
                         :only_allow_merge_if_all_discussions_are_resolved, :path,
                         :default_branch
       end
@@ -282,6 +283,8 @@ module API
       delete ":id" do
         authorize! :remove_project, user_project
         ::Projects::DestroyService.new(user_project, current_user, {}).async_execute
+
+        accepted!
       end
 
       desc 'Mark this project as forked from another'
@@ -351,7 +354,6 @@ module API
         not_found!('Group Link') unless link
 
         link.destroy
-        no_content!
       end
 
       desc 'Upload a file'
diff --git a/lib/api/runner.rb b/lib/api/runner.rb
new file mode 100644
index 00000000000..47858f1866b
--- /dev/null
+++ b/lib/api/runner.rb
@@ -0,0 +1,52 @@
+module API
+  class Runner < Grape::API
+    helpers ::API::Helpers::Runner
+
+    resource :runners do
+      desc 'Registers a new Runner' do
+        success Entities::RunnerRegistrationDetails
+        http_codes [[201, 'Runner was created'], [403, 'Forbidden']]
+      end
+      params do
+        requires :token, type: String, desc: 'Registration token'
+        optional :description, type: String, desc: %q(Runner's description)
+        optional :info, type: Hash, desc: %q(Runner's metadata)
+        optional :locked, type: Boolean, desc: 'Should Runner be locked for current project'
+        optional :run_untagged, type: Boolean, desc: 'Should Runner handle untagged jobs'
+        optional :tag_list, type: Array[String], desc: %q(List of Runner's tags)
+      end
+      post '/' do
+        attributes = attributes_for_keys [:description, :locked, :run_untagged, :tag_list]
+
+        runner =
+          if runner_registration_token_valid?
+            # Create shared runner. Requires admin access
+            Ci::Runner.create(attributes.merge(is_shared: true))
+          elsif project = Project.find_by(runners_token: params[:token])
+            # Create a specific runner for project.
+            project.runners.create(attributes)
+          end
+
+        return forbidden! unless runner
+
+        if runner.id
+          runner.update(get_runner_version_from_params)
+          present runner, with: Entities::RunnerRegistrationDetails
+        else
+          not_found!
+        end
+      end
+
+      desc 'Deletes a registered Runner' do
+        http_codes [[204, 'Runner was deleted'], [403, 'Forbidden']]
+      end
+      params do
+        requires :token, type: String, desc: %q(Runner's authentication token)
+      end
+      delete '/' do
+        authenticate_runner!
+        Ci::Runner.find_by_token(params[:token]).destroy
+      end
+    end
+  end
+end
diff --git a/lib/api/runners.rb b/lib/api/runners.rb
index 252e59bfa58..2e41f16f8c6 100644
--- a/lib/api/runners.rb
+++ b/lib/api/runners.rb
@@ -78,9 +78,8 @@ module API
       delete ':id' do
         runner = get_runner(params[:id])
         authenticate_delete_runner!(runner)
-        runner.destroy!
 
-        present runner, with: Entities::Runner
+        runner.destroy!
       end
     end
 
@@ -136,8 +135,6 @@ module API
         forbidden!("Only one project associated with the runner. Please remove the runner instead") if runner.projects.count == 1
 
         runner_project.destroy
-
-        present runner, with: Entities::Runner
       end
     end
 
diff --git a/lib/api/services.rb b/lib/api/services.rb
index 1456fe4688b..79a5f27dc4d 100644
--- a/lib/api/services.rb
+++ b/lib/api/services.rb
@@ -563,7 +563,20 @@ module API
       SlackService,
       MattermostService,
       TeamcityService,
-    ].freeze
+    ]
+
+    if Rails.env.development?
+      services['mock-ci'] = [
+        {
+          required: true,
+          name: :mock_service_url,
+          type: String,
+          desc: 'URL to the mock service'
+        }
+      ]
+
+      service_classes << MockCiService
+    end
 
     trigger_services = {
       'mattermost-slash-commands' => [
@@ -641,9 +654,7 @@ module API
           hash.merge!(key => nil)
         end
 
-        if service.update_attributes(attrs.merge(active: false))
-          true
-        else
+        unless service.update_attributes(attrs.merge(active: false))
           render_api_error!('400 Bad Request', 400)
         end
       end
diff --git a/lib/api/settings.rb b/lib/api/settings.rb
index 747ceb4e3e0..936c7e0930b 100644
--- a/lib/api/settings.rb
+++ b/lib/api/settings.rb
@@ -56,7 +56,8 @@ module API
       given shared_runners_enabled: ->(val) { val } do
         requires :shared_runners_text, type: String, desc: 'Shared runners text '
       end
-      optional :max_artifacts_size, type: Integer, desc: "Set the maximum file size each build's artifacts can have"
+      optional :max_artifacts_size, type: Integer, desc: "Set the maximum file size for each job's artifacts"
+      optional :default_artifacts_expire_in, type: String, desc: "Set the default expiration time for each job's artifacts"
       optional :max_pages_size, type: Integer, desc: 'Maximum size of pages in MB'
       optional :container_registry_token_expire_delay, type: Integer, desc: 'Authorization token duration (minutes)'
       optional :metrics_enabled, type: Boolean, desc: 'Enable the InfluxDB metrics'
@@ -117,7 +118,9 @@ module API
                       :send_user_confirmation_email, :domain_whitelist, :domain_blacklist_enabled,
                       :after_sign_up_text, :signin_enabled, :require_two_factor_authentication,
                       :home_page_url, :after_sign_out_path, :sign_in_text, :help_page_text,
-                      :shared_runners_enabled, :max_artifacts_size, :max_pages_size, :container_registry_token_expire_delay,
+                      :shared_runners_enabled, :max_artifacts_size,
+                      :default_artifacts_expire_in, :max_pages_size,
+                      :container_registry_token_expire_delay,
                       :metrics_enabled, :sidekiq_throttling_enabled, :recaptcha_enabled,
                       :akismet_enabled, :admin_notification_email, :sentry_enabled,
                       :repository_storage, :repository_checks_enabled, :koding_enabled, :plantuml_enabled,
diff --git a/lib/api/snippets.rb b/lib/api/snippets.rb
index ac03fbd2a3d..0f86fdb3075 100644
--- a/lib/api/snippets.rb
+++ b/lib/api/snippets.rb
@@ -118,9 +118,10 @@ module API
       delete ':id' do
         snippet = snippets_for_current_user.find_by(id: params.delete(:id))
         return not_found!('Snippet') unless snippet
+
         authorize! :destroy_personal_snippet, snippet
+
         snippet.destroy
-        no_content!
       end
 
       desc 'Get a raw snippet' do
diff --git a/lib/api/system_hooks.rb b/lib/api/system_hooks.rb
index d038a3fa828..ed7b23b474a 100644
--- a/lib/api/system_hooks.rb
+++ b/lib/api/system_hooks.rb
@@ -66,7 +66,7 @@ module API
         hook = SystemHook.find_by(id: params[:id])
         not_found!('System hook') unless hook
 
-        present hook.destroy, with: Entities::Hook
+        hook.destroy
       end
     end
   end
diff --git a/lib/api/tags.rb b/lib/api/tags.rb
index 86759ab882f..d31ef9de26b 100644
--- a/lib/api/tags.rb
+++ b/lib/api/tags.rb
@@ -66,11 +66,7 @@ module API
         result = ::Tags::DestroyService.new(user_project, current_user).
           execute(params[:tag_name])
 
-        if result[:status] == :success
-          {
-            tag_name: params[:tag_name]
-          }
-        else
+        if result[:status] != :success
           render_api_error!(result[:message], result[:return_code])
         end
       end
diff --git a/lib/api/triggers.rb b/lib/api/triggers.rb
index 87a717ba751..b7c9c5f2b7f 100644
--- a/lib/api/triggers.rb
+++ b/lib/api/triggers.rb
@@ -21,14 +21,9 @@ module API
         unauthorized! unless trigger.project == project
 
         # validate variables
-        variables = params[:variables]
-        if variables
-          unless variables.all? { |key, value| key.is_a?(String) && value.is_a?(String) }
-            render_api_error!('variables needs to be a map of key-valued strings', 400)
-          end
-
-          # convert variables from Mash to Hash
-          variables = variables.to_h
+        variables = params[:variables].to_h
+        unless variables.all? { |key, value| key.is_a?(String) && value.is_a?(String) }
+          render_api_error!('variables needs to be a map of key-valued strings', 400)
         end
 
         # create request and trigger builds
@@ -98,8 +93,6 @@ module API
         return not_found!('Trigger') unless trigger
 
         trigger.destroy
-
-        present trigger, with: Entities::Trigger
       end
     end
   end
diff --git a/lib/api/users.rb b/lib/api/users.rb
index 94b2b6653d2..7bb4b76f830 100644
--- a/lib/api/users.rb
+++ b/lib/api/users.rb
@@ -236,7 +236,7 @@ module API
         key = user.keys.find_by(id: params[:key_id])
         not_found!('Key') unless key
 
-        present key.destroy, with: Entities::SSHKey
+        key.destroy
       end
 
       desc 'Add an email address to a specified user. Available only for admins.' do
@@ -422,7 +422,7 @@ module API
         key = current_user.keys.find_by(id: params[:key_id])
         not_found!('Key') unless key
 
-        present key.destroy, with: Entities::SSHKey
+        key.destroy
       end
 
       desc "Get the currently authenticated user's email addresses" do
diff --git a/lib/api/v3/award_emoji.rb b/lib/api/v3/award_emoji.rb
new file mode 100644
index 00000000000..1e35283631f
--- /dev/null
+++ b/lib/api/v3/award_emoji.rb
@@ -0,0 +1,59 @@
+module API
+  module V3
+    class AwardEmoji < Grape::API
+      include PaginationParams
+
+      before { authenticate! }
+      AWARDABLES = %w[issue merge_request snippet].freeze
+
+      resource :projects do
+        AWARDABLES.each do |awardable_type|
+          awardable_string = awardable_type.pluralize
+          awardable_id_string = "#{awardable_type}_id"
+
+          params do
+            requires :id, type: String, desc: 'The ID of a project'
+            requires :"#{awardable_id_string}", type: Integer, desc: "The ID of an Issue, Merge Request or Snippet"
+          end
+
+          [":id/#{awardable_string}/:#{awardable_id_string}/award_emoji",
+           ":id/#{awardable_string}/:#{awardable_id_string}/notes/:note_id/award_emoji"].each do |endpoint|
+            desc 'Delete a +awardables+ award emoji' do
+              detail 'This feature was introduced in 8.9'
+              success ::API::Entities::AwardEmoji
+            end
+            params do
+              requires :award_id, type: Integer, desc: 'The ID of an award emoji'
+            end
+            delete "#{endpoint}/:award_id" do
+              award = awardable.award_emoji.find(params[:award_id])
+
+              unauthorized! unless award.user == current_user || current_user.admin?
+
+              present award.destroy, with: ::API::Entities::AwardEmoji
+            end
+          end
+        end
+      end
+
+      helpers do
+        def awardable
+          @awardable ||=
+            begin
+              if params.include?(:note_id)
+                note_id = params.delete(:note_id)
+
+                awardable.notes.find(note_id)
+              elsif params.include?(:issue_id)
+                user_project.issues.find(params[:issue_id])
+              elsif params.include?(:merge_request_id)
+                user_project.merge_requests.find(params[:merge_request_id])
+              else
+                user_project.snippets.find(params[:snippet_id])
+              end
+            end
+        end
+      end
+    end
+  end
+end
diff --git a/lib/api/v3/boards.rb b/lib/api/v3/boards.rb
index 31d708bc2c8..b1c2a3c59f2 100644
--- a/lib/api/v3/boards.rb
+++ b/lib/api/v3/boards.rb
@@ -44,6 +44,27 @@ module API
             authorize!(:read_board, user_project)
             present board_lists, with: ::API::Entities::List
           end
+
+          desc 'Delete a board list' do
+            detail 'This feature was introduced in 8.13'
+            success ::API::Entities::List
+          end
+          params do
+            requires :list_id, type: Integer, desc: 'The ID of a board list'
+          end
+          delete "/lists/:list_id" do
+            authorize!(:admin_list, user_project)
+
+            list = board_lists.find(params[:list_id])
+
+            service = ::Boards::Lists::DestroyService.new(user_project, current_user)
+
+            if service.execute(list)
+              present list, with: ::API::Entities::List
+            else
+              render_api_error!({ error: 'List could not be deleted!' }, 400)
+            end
+          end
         end
       end
     end
diff --git a/lib/api/v3/branches.rb b/lib/api/v3/branches.rb
index 733c6b21be5..699e41b5537 100644
--- a/lib/api/v3/branches.rb
+++ b/lib/api/v3/branches.rb
@@ -18,6 +18,33 @@ module API
 
           present branches, with: ::API::Entities::RepoBranch, project: user_project
         end
+
+        desc 'Delete a branch'
+        params do
+          requires :branch, type: String, desc: 'The name of the branch'
+        end
+        delete ":id/repository/branches/:branch", requirements: { branch: /.+/ } do
+          authorize_push_project
+
+          result = DeleteBranchService.new(user_project, current_user).
+                   execute(params[:branch])
+
+          if result[:status] == :success
+            status(200)
+            {
+              branch_name: params[:branch]
+            }
+          else
+            render_api_error!(result[:message], result[:return_code])
+          end
+        end
+
+        desc 'Delete all merged branches'
+        delete ":id/repository/merged_branches" do
+          DeleteMergedBranchesService.new(user_project, current_user).async_execute
+
+          status(200)
+        end
       end
     end
   end
diff --git a/lib/api/v3/broadcast_messages.rb b/lib/api/v3/broadcast_messages.rb
new file mode 100644
index 00000000000..417e4ad0b26
--- /dev/null
+++ b/lib/api/v3/broadcast_messages.rb
@@ -0,0 +1,31 @@
+module API
+  module V3
+    class BroadcastMessages < Grape::API
+      include PaginationParams
+
+      before { authenticate! }
+      before { authenticated_as_admin! }
+
+      resource :broadcast_messages do
+        helpers do
+          def find_message
+            BroadcastMessage.find(params[:id])
+          end
+        end
+
+        desc 'Delete a broadcast message' do
+          detail 'This feature was introduced in GitLab 8.12.'
+          success ::API::Entities::BroadcastMessage
+        end
+        params do
+          requires :id, type: Integer, desc: 'Broadcast message ID'
+        end
+        delete ':id' do
+          message = find_message
+
+          present message.destroy, with: ::API::Entities::BroadcastMessage
+        end
+      end
+    end
+  end
+end
diff --git a/lib/api/v3/commits.rb b/lib/api/v3/commits.rb
index 126cc95fc3d..506204b3517 100644
--- a/lib/api/v3/commits.rb
+++ b/lib/api/v3/commits.rb
@@ -55,13 +55,6 @@ module API
           branch = attrs.delete(:branch_name)
           attrs.merge!(branch: branch, start_branch: branch, target_branch: branch)
 
-          attrs[:actions].map! do |action|
-            action[:action] = action[:action].to_sym
-            action[:file_path].slice!(0) if action[:file_path] && action[:file_path].start_with?('/')
-            action[:previous_path].slice!(0) if action[:previous_path] && action[:previous_path].start_with?('/')
-            action
-          end
-
           result = ::Files::MultiService.new(user_project, current_user, attrs).execute
 
           if result[:status] == :success
diff --git a/lib/api/v3/entities.rb b/lib/api/v3/entities.rb
index 11d0e6dbf71..2a3dcb7f288 100644
--- a/lib/api/v3/entities.rb
+++ b/lib/api/v3/entities.rb
@@ -45,6 +45,86 @@ module API
         expose :created_at, :updated_at
         expose :awardable_id, :awardable_type
       end
+
+      class Project < Grape::Entity
+        expose :id, :description, :default_branch, :tag_list
+        expose :public?, as: :public
+        expose :archived?, as: :archived
+        expose :visibility_level, :ssh_url_to_repo, :http_url_to_repo, :web_url
+        expose :owner, using: ::API::Entities::UserBasic, unless: ->(project, options) { project.group }
+        expose :name, :name_with_namespace
+        expose :path, :path_with_namespace
+        expose :container_registry_enabled
+
+        # Expose old field names with the new permissions methods to keep API compatible
+        expose(:issues_enabled) { |project, options| project.feature_available?(:issues, options[:current_user]) }
+        expose(:merge_requests_enabled) { |project, options| project.feature_available?(:merge_requests, options[:current_user]) }
+        expose(:wiki_enabled) { |project, options| project.feature_available?(:wiki, options[:current_user]) }
+        expose(:builds_enabled) { |project, options| project.feature_available?(:builds, options[:current_user]) }
+        expose(:snippets_enabled) { |project, options| project.feature_available?(:snippets, options[:current_user]) }
+
+        expose :created_at, :last_activity_at
+        expose :shared_runners_enabled
+        expose :lfs_enabled?, as: :lfs_enabled
+        expose :creator_id
+        expose :namespace, using: 'API::Entities::Namespace'
+        expose :forked_from_project, using: ::API::Entities::BasicProjectDetails, if: lambda{ |project, options| project.forked? }
+        expose :avatar_url
+        expose :star_count, :forks_count
+        expose :open_issues_count, if: lambda { |project, options| project.feature_available?(:issues, options[:current_user]) && project.default_issues_tracker? }
+        expose :runners_token, if: lambda { |_project, options| options[:user_can_admin_project] }
+        expose :public_builds
+        expose :shared_with_groups do |project, options|
+          ::API::Entities::SharedGroup.represent(project.project_group_links.all, options)
+        end
+        expose :only_allow_merge_if_pipeline_succeeds, as: :only_allow_merge_if_build_succeeds
+        expose :request_access_enabled
+        expose :only_allow_merge_if_all_discussions_are_resolved
+
+        expose :statistics, using: 'API::Entities::ProjectStatistics', if: :statistics
+      end
+
+      class ProjectWithAccess < Project
+        expose :permissions do
+          expose :project_access, using: ::API::Entities::ProjectAccess do |project, options|
+            project.project_members.find_by(user_id: options[:current_user].id)
+          end
+
+          expose :group_access, using: ::API::Entities::GroupAccess do |project, options|
+            if project.group
+              project.group.group_members.find_by(user_id: options[:current_user].id)
+            end
+          end
+        end
+      end
+
+      class MergeRequest < Grape::Entity
+        expose :id, :iid
+        expose(:project_id) { |entity| entity.project.id }
+        expose :title, :description
+        expose :state, :created_at, :updated_at
+        expose :target_branch, :source_branch
+        expose :upvotes, :downvotes
+        expose :author, :assignee, using: ::API::Entities::UserBasic
+        expose :source_project_id, :target_project_id
+        expose :label_names, as: :labels
+        expose :work_in_progress?, as: :work_in_progress
+        expose :milestone, using: ::API::Entities::Milestone
+        expose :merge_when_pipeline_succeeds, as: :merge_when_build_succeeds
+        expose :merge_status
+        expose :diff_head_sha, as: :sha
+        expose :merge_commit_sha
+        expose :subscribed do |merge_request, options|
+          merge_request.subscribed?(options[:current_user], options[:project])
+        end
+        expose :user_notes_count
+        expose :should_remove_source_branch?, as: :should_remove_source_branch
+        expose :force_remove_source_branch?, as: :force_remove_source_branch
+
+        expose :web_url do |merge_request, options|
+          Gitlab::UrlBuilder.build(merge_request)
+        end
+      end
     end
   end
 end
diff --git a/lib/api/v3/environments.rb b/lib/api/v3/environments.rb
new file mode 100644
index 00000000000..3effccfa708
--- /dev/null
+++ b/lib/api/v3/environments.rb
@@ -0,0 +1,29 @@
+module API
+  module V3
+    class Environments < Grape::API
+      include PaginationParams
+
+      before { authenticate! }
+
+      params do
+        requires :id, type: String, desc: 'The project ID'
+      end
+      resource :projects do
+        desc 'Deletes an existing environment' do
+          detail 'This feature was introduced in GitLab 8.11.'
+          success ::API::Entities::Environment
+        end
+        params do
+          requires :environment_id, type: Integer,  desc: 'The environment ID'
+        end
+        delete ':id/environments/:environment_id' do
+          authorize! :update_environment, user_project
+
+          environment = user_project.environments.find(params[:environment_id])
+
+          present environment.destroy, with: ::API::Entities::Environment
+        end
+      end
+    end
+  end
+end
diff --git a/lib/api/v3/groups.rb b/lib/api/v3/groups.rb
new file mode 100644
index 00000000000..c826bc4fe0b
--- /dev/null
+++ b/lib/api/v3/groups.rb
@@ -0,0 +1,38 @@
+module API
+  module V3
+    class Groups < Grape::API
+      include PaginationParams
+
+      before { authenticate! }
+
+      helpers do
+        params :statistics_params do
+          optional :statistics, type: Boolean, default: false, desc: 'Include project statistics'
+        end
+
+        def present_groups(groups, options = {})
+          options = options.reverse_merge(
+            with: ::API::Entities::Group,
+            current_user: current_user,
+          )
+
+          groups = groups.with_statistics if options[:statistics]
+          present paginate(groups), options
+        end
+      end
+
+      resource :groups do
+        desc 'Get list of owned groups for authenticated user' do
+          success ::API::Entities::Group
+        end
+        params do
+          use :pagination
+          use :statistics_params
+        end
+        get '/owned' do
+          present_groups current_user.owned_groups, statistics: params[:statistics]
+        end
+      end
+    end
+  end
+end
diff --git a/lib/api/v3/issues.rb b/lib/api/v3/issues.rb
index d0af09f0e1e..5d7dfabfcd6 100644
--- a/lib/api/v3/issues.rb
+++ b/lib/api/v3/issues.rb
@@ -226,6 +226,8 @@ module API
           not_found!('Issue') unless issue
 
           authorize!(:destroy_issue, issue)
+
+          status(200)
           issue.destroy
         end
       end
diff --git a/lib/api/v3/labels.rb b/lib/api/v3/labels.rb
index 5c3261311bf..41f45d244e3 100644
--- a/lib/api/v3/labels.rb
+++ b/lib/api/v3/labels.rb
@@ -13,6 +13,21 @@ module API
         get ':id/labels' do
           present available_labels, with: ::API::Entities::Label, current_user: current_user, project: user_project
         end
+
+        desc 'Delete an existing label' do
+          success ::API::Entities::Label
+        end
+        params do
+          requires :name, type: String, desc: 'The name of the label to be deleted'
+        end
+        delete ':id/labels' do
+          authorize! :admin_label, user_project
+
+          label = user_project.labels.find_by(title: params[:name])
+          not_found!('Label') unless label
+
+          present label.destroy, with: ::API::Entities::Label, current_user: current_user, project: user_project
+        end
       end
     end
   end
diff --git a/lib/api/v3/members.rb b/lib/api/v3/members.rb
index 19f276d5484..3d4972afd9d 100644
--- a/lib/api/v3/members.rb
+++ b/lib/api/v3/members.rb
@@ -119,6 +119,7 @@ module API
             # This is to ensure back-compatibility but 204 behavior should be used
             # for all DELETE endpoints in 9.0!
             if member.nil?
+              status(200  )
               { message: "Access revoked", id: params[:user_id].to_i }
             else
               ::Members::DestroyService.new(source, current_user, declared_params).execute
diff --git a/lib/api/v3/merge_requests.rb b/lib/api/v3/merge_requests.rb
index 129f9d850e9..654e818e1b5 100644
--- a/lib/api/v3/merge_requests.rb
+++ b/lib/api/v3/merge_requests.rb
@@ -39,7 +39,7 @@ module API
 
         desc 'List merge requests' do
           detail 'iid filter is deprecated have been removed on V4'
-          success ::API::Entities::MergeRequest
+          success ::API::V3::Entities::MergeRequest
         end
         params do
           optional :state, type: String, values: %w[opened closed merged all], default: 'all',
@@ -66,11 +66,11 @@ module API
             end
 
           merge_requests = merge_requests.reorder(params[:order_by] => params[:sort])
-          present paginate(merge_requests), with: ::API::Entities::MergeRequest, current_user: current_user, project: user_project
+          present paginate(merge_requests), with: ::API::V3::Entities::MergeRequest, current_user: current_user, project: user_project
         end
 
         desc 'Create a merge request' do
-          success ::API::Entities::MergeRequest
+          success ::API::V3::Entities::MergeRequest
         end
         params do
           requires :title, type: String, desc: 'The title of the merge request'
@@ -89,7 +89,7 @@ module API
           merge_request = ::MergeRequests::CreateService.new(user_project, current_user, mr_params).execute
 
           if merge_request.valid?
-            present merge_request, with: ::API::Entities::MergeRequest, current_user: current_user, project: user_project
+            present merge_request, with: ::API::V3::Entities::MergeRequest, current_user: current_user, project: user_project
           else
             handle_merge_request_errors! merge_request.errors
           end
@@ -103,6 +103,8 @@ module API
           merge_request = find_project_merge_request(params[:merge_request_id])
 
           authorize!(:destroy_merge_request, merge_request)
+
+          status(200)
           merge_request.destroy
         end
 
@@ -114,12 +116,12 @@ module API
             if status == :deprecated
               detail DEPRECATION_MESSAGE
             end
-            success ::API::Entities::MergeRequest
+            success ::API::V3::Entities::MergeRequest
           end
           get path do
             merge_request = find_merge_request_with_access(params[:merge_request_id])
 
-            present merge_request, with: ::API::Entities::MergeRequest, current_user: current_user, project: user_project
+            present merge_request, with: ::API::V3::Entities::MergeRequest, current_user: current_user, project: user_project
           end
 
           desc 'Get the commits of a merge request' do
@@ -141,7 +143,7 @@ module API
           end
 
           desc 'Update a merge request' do
-            success ::API::Entities::MergeRequest
+            success ::API::V3::Entities::MergeRequest
           end
           params do
             optional :title, type: String, allow_blank: false, desc: 'The title of the merge request'
@@ -162,21 +164,21 @@ module API
             merge_request = ::MergeRequests::UpdateService.new(user_project, current_user, mr_params).execute(merge_request)
 
             if merge_request.valid?
-              present merge_request, with: ::API::Entities::MergeRequest, current_user: current_user, project: user_project
+              present merge_request, with: ::API::V3::Entities::MergeRequest, current_user: current_user, project: user_project
             else
               handle_merge_request_errors! merge_request.errors
             end
           end
 
           desc 'Merge a merge request' do
-            success ::API::Entities::MergeRequest
+            success ::API::V3::Entities::MergeRequest
           end
           params do
             optional :merge_commit_message, type: String, desc: 'Custom merge commit message'
             optional :should_remove_source_branch, type: Boolean,
                                                    desc: 'When true, the source branch will be deleted if possible'
             optional :merge_when_build_succeeds, type: Boolean,
-                                                 desc: 'When true, this merge request will be merged when the pipeline succeeds'
+                                                 desc: 'When true, this merge request will be merged when the build succeeds'
             optional :sha, type: String, desc: 'When present, must have the HEAD SHA of the source branch'
           end
           put "#{path}/merge" do
@@ -209,16 +211,16 @@ module API
                 .execute(merge_request)
             end
 
-            present merge_request, with: ::API::Entities::MergeRequest, current_user: current_user, project: user_project
+            present merge_request, with: ::API::V3::Entities::MergeRequest, current_user: current_user, project: user_project
           end
 
-          desc 'Cancel merge if "Merge When Pipeline Succeeds" is enabled' do
-            success ::API::Entities::MergeRequest
+          desc 'Cancel merge if "Merge When Build succeeds" is enabled' do
+            success ::API::V3::Entities::MergeRequest
           end
           post "#{path}/cancel_merge_when_build_succeeds" do
             merge_request = find_project_merge_request(params[:merge_request_id])
 
-            unauthorized! unless merge_request.can_cancel_merge_when_build_succeeds?(current_user)
+            unauthorized! unless merge_request.can_cancel_merge_when_pipeline_succeeds?(current_user)
 
             ::MergeRequest::MergeWhenPipelineSucceedsService
               .new(merge_request.target_project, current_user)
diff --git a/lib/api/v3/project_snippets.rb b/lib/api/v3/project_snippets.rb
index e03e941d30b..809ca4f37ba 100644
--- a/lib/api/v3/project_snippets.rb
+++ b/lib/api/v3/project_snippets.rb
@@ -121,6 +121,8 @@ module API
 
           authorize! :admin_project_snippet, snippet
           snippet.destroy
+
+          status(200)
         end
 
         desc 'Get a raw project snippet'
diff --git a/lib/api/v3/projects.rb b/lib/api/v3/projects.rb
index c3821555452..47bfc12035a 100644
--- a/lib/api/v3/projects.rb
+++ b/lib/api/v3/projects.rb
@@ -5,6 +5,10 @@ module API
 
       before { authenticate_non_get! }
 
+      after_validation do
+        set_only_allow_merge_if_pipeline_succeeds!
+      end
+
       helpers do
         params :optional_params do
           optional :description, type: String, desc: 'The description of the project'
@@ -25,6 +29,7 @@ module API
           optional :public_builds, type: Boolean, desc: 'Perform public builds'
           optional :request_access_enabled, type: Boolean, desc: 'Allow users to request member access'
           optional :only_allow_merge_if_build_succeeds, type: Boolean, desc: 'Only allow to merge if builds succeed'
+          optional :only_allow_merge_if_pipeline_succeeds, type: Boolean, desc: 'Only allow to merge if builds succeed'
           optional :only_allow_merge_if_all_discussions_are_resolved, type: Boolean, desc: 'Only allow to merge if all discussions are resolved'
         end
 
@@ -37,6 +42,12 @@ module API
           end
           attrs
         end
+
+        def set_only_allow_merge_if_pipeline_succeeds!
+          if params.has_key?(:only_allow_merge_if_build_succeeds)
+            params[:only_allow_merge_if_pipeline_succeeds] = params.delete(:only_allow_merge_if_build_succeeds)
+          end
+        end
       end
 
       resource :projects do
@@ -75,7 +86,7 @@ module API
 
           def present_projects(projects, options = {})
             options = options.reverse_merge(
-              with: ::API::Entities::Project,
+              with: ::API::V3::Entities::Project,
               current_user: current_user,
               simple: params[:simple],
             )
@@ -95,7 +106,7 @@ module API
           use :collection_params
         end
         get '/visible' do
-          entity = current_user ? ::API::Entities::ProjectWithAccess : ::API::Entities::BasicProjectDetails
+          entity = current_user ? ::API::V3::Entities::ProjectWithAccess : ::API::Entities::BasicProjectDetails
           present_projects ProjectsFinder.new.execute(current_user), with: entity
         end
 
@@ -109,7 +120,7 @@ module API
           authenticate!
 
           present_projects current_user.authorized_projects,
-            with: ::API::Entities::ProjectWithAccess
+            with: ::API::V3::Entities::ProjectWithAccess
         end
 
         desc 'Get an owned projects list for authenticated user' do
@@ -123,7 +134,7 @@ module API
           authenticate!
 
           present_projects current_user.owned_projects,
-            with: ::API::Entities::ProjectWithAccess,
+            with: ::API::V3::Entities::ProjectWithAccess,
             statistics: params[:statistics]
         end
 
@@ -149,11 +160,11 @@ module API
         get '/all' do
           authenticated_as_admin!
 
-          present_projects Project.all, with: ::API::Entities::ProjectWithAccess, statistics: params[:statistics]
+          present_projects Project.all, with: ::API::V3::Entities::ProjectWithAccess, statistics: params[:statistics]
         end
 
         desc 'Search for projects the current user has access to' do
-          success ::API::Entities::Project
+          success ::API::V3::Entities::Project
         end
         params do
           requires :query, type: String, desc: 'The project name to be searched'
@@ -165,15 +176,16 @@ module API
           projects = search_service.objects('projects', params[:page])
           projects = projects.reorder(params[:order_by] => params[:sort])
 
-          present paginate(projects), with: ::API::Entities::Project
+          present paginate(projects), with: ::API::V3::Entities::Project
         end
 
         desc 'Create new project' do
-          success ::API::Entities::Project
+          success ::API::V3::Entities::Project
         end
         params do
-          requires :name, type: String, desc: 'The name of the project'
+          optional :name, type: String, desc: 'The name of the project'
           optional :path, type: String, desc: 'The path of the repository'
+          at_least_one_of :name, :path
           use :optional_params
           use :create_params
         end
@@ -182,7 +194,7 @@ module API
           project = ::Projects::CreateService.new(current_user, attrs).execute
 
           if project.saved?
-            present project, with: ::API::Entities::Project,
+            present project, with: ::API::V3::Entities::Project,
                              user_can_admin_project: can?(current_user, :admin_project, project)
           else
             if project.errors[:limit_reached].present?
@@ -193,7 +205,7 @@ module API
         end
 
         desc 'Create new project for a specified user. Only available to admin users.' do
-          success ::API::Entities::Project
+          success ::API::V3::Entities::Project
         end
         params do
           requires :name, type: String, desc: 'The name of the project'
@@ -211,7 +223,7 @@ module API
           project = ::Projects::CreateService.new(user, attrs).execute
 
           if project.saved?
-            present project, with: ::API::Entities::Project,
+            present project, with: ::API::V3::Entities::Project,
                              user_can_admin_project: can?(current_user, :admin_project, project)
           else
             render_validation_error!(project)
@@ -224,10 +236,10 @@ module API
       end
       resource :projects, requirements: { id: /[^\/]+/ } do
         desc 'Get a single project' do
-          success ::API::Entities::ProjectWithAccess
+          success ::API::V3::Entities::ProjectWithAccess
         end
         get ":id" do
-          entity = current_user ? ::API::Entities::ProjectWithAccess : ::API::Entities::BasicProjectDetails
+          entity = current_user ? ::API::V3::Entities::ProjectWithAccess : ::API::Entities::BasicProjectDetails
           present user_project, with: entity, current_user: current_user,
                                 user_can_admin_project: can?(current_user, :admin_project, user_project)
         end
@@ -243,7 +255,7 @@ module API
         end
 
         desc 'Fork new project for the current user or provided namespace.' do
-          success ::API::Entities::Project
+          success ::API::V3::Entities::Project
         end
         params do
           optional :namespace, type: String, desc: 'The ID or name of the namespace that the project will be forked into'
@@ -269,13 +281,13 @@ module API
           if forked_project.errors.any?
             conflict!(forked_project.errors.messages)
           else
-            present forked_project, with: ::API::Entities::Project,
+            present forked_project, with: ::API::V3::Entities::Project,
                                     user_can_admin_project: can?(current_user, :admin_project, forked_project)
           end
         end
 
         desc 'Update an existing project' do
-          success ::API::Entities::Project
+          success ::API::V3::Entities::Project
         end
         params do
           optional :name, type: String, desc: 'The name of the project'
@@ -299,7 +311,7 @@ module API
           result = ::Projects::UpdateService.new(user_project, current_user, attrs).execute
 
           if result[:status] == :success
-            present user_project, with: ::API::Entities::Project,
+            present user_project, with: ::API::V3::Entities::Project,
                                   user_can_admin_project: can?(current_user, :admin_project, user_project)
           else
             render_validation_error!(user_project)
@@ -307,29 +319,29 @@ module API
         end
 
         desc 'Archive a project' do
-          success ::API::Entities::Project
+          success ::API::V3::Entities::Project
         end
         post ':id/archive' do
           authorize!(:archive_project, user_project)
 
           user_project.archive!
 
-          present user_project, with: ::API::Entities::Project
+          present user_project, with: ::API::V3::Entities::Project
         end
 
         desc 'Unarchive a project' do
-          success ::API::Entities::Project
+          success ::API::V3::Entities::Project
         end
         post ':id/unarchive' do
           authorize!(:archive_project, user_project)
 
           user_project.unarchive!
 
-          present user_project, with: ::API::Entities::Project
+          present user_project, with: ::API::V3::Entities::Project
         end
 
         desc 'Star a project' do
-          success ::API::Entities::Project
+          success ::API::V3::Entities::Project
         end
         post ':id/star' do
           if current_user.starred?(user_project)
@@ -338,19 +350,19 @@ module API
             current_user.toggle_star(user_project)
             user_project.reload
 
-            present user_project, with: ::API::Entities::Project
+            present user_project, with: ::API::V3::Entities::Project
           end
         end
 
         desc 'Unstar a project' do
-          success ::API::Entities::Project
+          success ::API::V3::Entities::Project
         end
         delete ':id/star' do
           if current_user.starred?(user_project)
             current_user.toggle_star(user_project)
             user_project.reload
 
-            present user_project, with: ::API::Entities::Project
+            present user_project, with: ::API::V3::Entities::Project
           else
             not_modified!
           end
@@ -359,6 +371,8 @@ module API
         desc 'Remove a project'
         delete ":id" do
           authorize! :remove_project, user_project
+
+          status(200)
           ::Projects::DestroyService.new(user_project, current_user, {}).async_execute
         end
 
@@ -384,6 +398,7 @@ module API
           authorize! :remove_fork_project, user_project
 
           if user_project.forked?
+            status(200)
             user_project.forked_project_link.destroy
           else
             not_modified!
diff --git a/lib/api/v3/runners.rb b/lib/api/v3/runners.rb
new file mode 100644
index 00000000000..8967141fe3d
--- /dev/null
+++ b/lib/api/v3/runners.rb
@@ -0,0 +1,65 @@
+module API
+  module V3
+    class Runners < Grape::API
+      include PaginationParams
+
+      before { authenticate! }
+
+      resource :runners do
+        desc 'Remove a runner' do
+          success ::API::Entities::Runner
+        end
+        params do
+          requires :id, type: Integer, desc: 'The ID of the runner'
+        end
+        delete ':id' do
+          runner = Ci::Runner.find(params[:id])
+          not_found!('Runner') unless runner
+
+          authenticate_delete_runner!(runner)
+
+          status(200)
+          runner.destroy
+        end
+      end
+
+      params do
+        requires :id, type: String, desc: 'The ID of a project'
+      end
+      resource :projects do
+        before { authorize_admin_project }
+
+        desc "Disable project's runner" do
+          success ::API::Entities::Runner
+        end
+        params do
+          requires :runner_id, type: Integer, desc: 'The ID of the runner'
+        end
+        delete ':id/runners/:runner_id' do
+          runner_project = user_project.runner_projects.find_by(runner_id: params[:runner_id])
+          not_found!('Runner') unless runner_project
+
+          runner = runner_project.runner
+          forbidden!("Only one project associated with the runner. Please remove the runner instead") if runner.projects.count == 1
+
+          runner_project.destroy
+
+          present runner, with: ::API::Entities::Runner
+        end
+      end
+
+      helpers do
+        def authenticate_delete_runner!(runner)
+          return if current_user.is_admin?
+          forbidden!("Runner is shared") if runner.is_shared?
+          forbidden!("Runner associated with more than one project") if runner.projects.count > 1
+          forbidden!("No access granted") unless user_can_access_runner?(runner)
+        end
+
+        def user_can_access_runner?(runner)
+          current_user.ci_authorized_runners.exists?(runner.id)
+        end
+      end
+    end
+  end
+end
diff --git a/lib/api/v3/services.rb b/lib/api/v3/services.rb
new file mode 100644
index 00000000000..af0a058f69b
--- /dev/null
+++ b/lib/api/v3/services.rb
@@ -0,0 +1,573 @@
+module API
+  module V3
+    class Services < Grape::API
+      services = {
+        'asana' => [
+          {
+            required: true,
+            name: :api_key,
+            type: String,
+            desc: 'User API token'
+          },
+          {
+            required: false,
+            name: :restrict_to_branch,
+            type: String,
+            desc: 'Comma-separated list of branches which will be automatically inspected. Leave blank to include all branches'
+          }
+        ],
+        'assembla' => [
+          {
+            required: true,
+            name: :token,
+            type: String,
+            desc: 'The authentication token'
+          },
+          {
+            required: false,
+            name: :subdomain,
+            type: String,
+            desc: 'Subdomain setting'
+          }
+        ],
+        'bamboo' => [
+          {
+            required: true,
+            name: :bamboo_url,
+            type: String,
+            desc: 'Bamboo root URL like https://bamboo.example.com'
+          },
+          {
+            required: true,
+            name: :build_key,
+            type: String,
+            desc: 'Bamboo build plan key like'
+          },
+          {
+            required: true,
+            name: :username,
+            type: String,
+            desc: 'A user with API access, if applicable'
+          },
+          {
+            required: true,
+            name: :password,
+            type: String,
+            desc: 'Passord of the user'
+          }
+        ],
+        'bugzilla' => [
+          {
+            required: true,
+            name: :new_issue_url,
+            type: String,
+            desc: 'New issue URL'
+          },
+          {
+            required: true,
+            name: :issues_url,
+            type: String,
+            desc: 'Issues URL'
+          },
+          {
+            required: true,
+            name: :project_url,
+            type: String,
+            desc: 'Project URL'
+          },
+          {
+            required: false,
+            name: :description,
+            type: String,
+            desc: 'Description'
+          },
+          {
+            required: false,
+            name: :title,
+            type: String,
+            desc: 'Title'
+          }
+        ],
+        'buildkite' => [
+          {
+            required: true,
+            name: :token,
+            type: String,
+            desc: 'Buildkite project GitLab token'
+          },
+          {
+            required: true,
+            name: :project_url,
+            type: String,
+            desc: 'The buildkite project URL'
+          },
+          {
+            required: false,
+            name: :enable_ssl_verification,
+            type: Boolean,
+            desc: 'Enable SSL verification for communication'
+          }
+        ],
+        'builds-email' => [
+          {
+            required: true,
+            name: :recipients,
+            type: String,
+            desc: 'Comma-separated list of recipient email addresses'
+          },
+          {
+            required: false,
+            name: :add_pusher,
+            type: Boolean,
+            desc: 'Add pusher to recipients list'
+          },
+          {
+            required: false,
+            name: :notify_only_broken_builds,
+            type: Boolean,
+            desc: 'Notify only broken builds'
+          }
+        ],
+        'campfire' => [
+          {
+            required: true,
+            name: :token,
+            type: String,
+            desc: 'Campfire token'
+          },
+          {
+            required: false,
+            name: :subdomain,
+            type: String,
+            desc: 'Campfire subdomain'
+          },
+          {
+            required: false,
+            name: :room,
+            type: String,
+            desc: 'Campfire room'
+          }
+        ],
+        'custom-issue-tracker' => [
+          {
+            required: true,
+            name: :new_issue_url,
+            type: String,
+            desc: 'New issue URL'
+          },
+          {
+            required: true,
+            name: :issues_url,
+            type: String,
+            desc: 'Issues URL'
+          },
+          {
+            required: true,
+            name: :project_url,
+            type: String,
+            desc: 'Project URL'
+          },
+          {
+            required: false,
+            name: :description,
+            type: String,
+            desc: 'Description'
+          },
+          {
+            required: false,
+            name: :title,
+            type: String,
+            desc: 'Title'
+          }
+        ],
+        'drone-ci' => [
+          {
+            required: true,
+            name: :token,
+            type: String,
+            desc: 'Drone CI token'
+          },
+          {
+            required: true,
+            name: :drone_url,
+            type: String,
+            desc: 'Drone CI URL'
+          },
+          {
+            required: false,
+            name: :enable_ssl_verification,
+            type: Boolean,
+            desc: 'Enable SSL verification for communication'
+          }
+        ],
+        'emails-on-push' => [
+          {
+            required: true,
+            name: :recipients,
+            type: String,
+            desc: 'Comma-separated list of recipient email addresses'
+          },
+          {
+            required: false,
+            name: :disable_diffs,
+            type: Boolean,
+            desc: 'Disable code diffs'
+          },
+          {
+            required: false,
+            name: :send_from_committer_email,
+            type: Boolean,
+            desc: 'Send from committer'
+          }
+        ],
+        'external-wiki' => [
+          {
+            required: true,
+            name: :external_wiki_url,
+            type: String,
+            desc: 'The URL of the external Wiki'
+          }
+        ],
+        'flowdock' => [
+          {
+            required: true,
+            name: :token,
+            type: String,
+            desc: 'Flowdock token'
+          }
+        ],
+        'gemnasium' => [
+          {
+            required: true,
+            name: :api_key,
+            type: String,
+            desc: 'Your personal API key on gemnasium.com'
+          },
+          {
+            required: true,
+            name: :token,
+            type: String,
+            desc: "The project's slug on gemnasium.com"
+          }
+        ],
+        'hipchat' => [
+          {
+            required: true,
+            name: :token,
+            type: String,
+            desc: 'The room token'
+          },
+          {
+            required: false,
+            name: :room,
+            type: String,
+            desc: 'The room name or ID'
+          },
+          {
+            required: false,
+            name: :color,
+            type: String,
+            desc: 'The room color'
+          },
+          {
+            required: false,
+            name: :notify,
+            type: Boolean,
+            desc: 'Enable notifications'
+          },
+          {
+            required: false,
+            name: :api_version,
+            type: String,
+            desc: 'Leave blank for default (v2)'
+          },
+          {
+            required: false,
+            name: :server,
+            type: String,
+            desc: 'Leave blank for default. https://hipchat.example.com'
+          }
+        ],
+        'irker' => [
+          {
+            required: true,
+            name: :recipients,
+            type: String,
+            desc: 'Recipients/channels separated by whitespaces'
+          },
+          {
+            required: false,
+            name: :default_irc_uri,
+            type: String,
+            desc: 'Default: irc://irc.network.net:6697'
+          },
+          {
+            required: false,
+            name: :server_host,
+            type: String,
+            desc: 'Server host. Default localhost'
+          },
+          {
+            required: false,
+            name: :server_port,
+            type: Integer,
+            desc: 'Server port. Default 6659'
+          },
+          {
+            required: false,
+            name: :colorize_messages,
+            type: Boolean,
+            desc: 'Colorize messages'
+          }
+        ],
+        'jira' => [
+          {
+            required: true,
+            name: :url,
+            type: String,
+            desc: 'The URL to the JIRA project which is being linked to this GitLab project, e.g., https://jira.example.com'
+          },
+          {
+            required: true,
+            name: :project_key,
+            type: String,
+            desc: 'The short identifier for your JIRA project, all uppercase, e.g., PROJ'
+          },
+          {
+            required: false,
+            name: :username,
+            type: String,
+            desc: 'The username of the user created to be used with GitLab/JIRA'
+          },
+          {
+            required: false,
+            name: :password,
+            type: String,
+            desc: 'The password of the user created to be used with GitLab/JIRA'
+          },
+          {
+            required: false,
+            name: :jira_issue_transition_id,
+            type: Integer,
+            desc: 'The ID of a transition that moves issues to a closed state. You can find this number under the JIRA workflow administration (**Administration > Issues > Workflows**) by selecting **View** under **Operations** of the desired workflow of your project. The ID of each state can be found inside the parenthesis of each transition name under the **Transitions (id)** column ([see screenshot][trans]). By default, this ID is set to `2`'
+          }
+        ],
+
+        'kubernetes' => [
+          {
+            required: true,
+            name: :namespace,
+            type: String,
+            desc: 'The Kubernetes namespace to use'
+          },
+          {
+            required: true,
+            name: :api_url,
+            type: String,
+            desc: 'The URL to the Kubernetes cluster API, e.g., https://kubernetes.example.com'
+          },
+          {
+            required: true,
+            name: :token,
+            type: String,
+            desc: 'The service token to authenticate against the Kubernetes cluster with'
+          },
+          {
+            required: false,
+            name: :ca_pem,
+            type: String,
+            desc: 'A custom certificate authority bundle to verify the Kubernetes cluster with (PEM format)'
+          },
+        ],
+        'mattermost-slash-commands' => [
+          {
+            required: true,
+            name: :token,
+            type: String,
+            desc: 'The Mattermost token'
+          }
+        ],
+        'slack-slash-commands' => [
+          {
+            required: true,
+            name: :token,
+            type: String,
+            desc: 'The Slack token'
+          }
+        ],
+        'pipelines-email' => [
+          {
+            required: true,
+            name: :recipients,
+            type: String,
+            desc: 'Comma-separated list of recipient email addresses'
+          },
+          {
+            required: false,
+            name: :notify_only_broken_builds,
+            type: Boolean,
+            desc: 'Notify only broken builds'
+          }
+        ],
+        'pivotaltracker' => [
+          {
+            required: true,
+            name: :token,
+            type: String,
+            desc: 'The Pivotaltracker token'
+          },
+          {
+            required: false,
+            name: :restrict_to_branch,
+            type: String,
+            desc: 'Comma-separated list of branches which will be automatically inspected. Leave blank to include all branches.'
+          }
+        ],
+        'pushover' => [
+          {
+            required: true,
+            name: :api_key,
+            type: String,
+            desc: 'The application key'
+          },
+          {
+            required: true,
+            name: :user_key,
+            type: String,
+            desc: 'The user key'
+          },
+          {
+            required: true,
+            name: :priority,
+            type: String,
+            desc: 'The priority'
+          },
+          {
+            required: true,
+            name: :device,
+            type: String,
+            desc: 'Leave blank for all active devices'
+          },
+          {
+            required: true,
+            name: :sound,
+            type: String,
+            desc: 'The sound of the notification'
+          }
+        ],
+        'redmine' => [
+          {
+            required: true,
+            name: :new_issue_url,
+            type: String,
+            desc: 'The new issue URL'
+          },
+          {
+            required: true,
+            name: :project_url,
+            type: String,
+            desc: 'The project URL'
+          },
+          {
+            required: true,
+            name: :issues_url,
+            type: String,
+            desc: 'The issues URL'
+          },
+          {
+            required: false,
+            name: :description,
+            type: String,
+            desc: 'The description of the tracker'
+          }
+        ],
+        'slack' => [
+          {
+            required: true,
+            name: :webhook,
+            type: String,
+            desc: 'The Slack webhook. e.g. https://hooks.slack.com/services/...'
+          },
+          {
+            required: false,
+            name: :new_issue_url,
+            type: String,
+            desc: 'The user name'
+          },
+          {
+            required: false,
+            name: :channel,
+            type: String,
+            desc: 'The channel name'
+          }
+        ],
+        'mattermost' => [
+          {
+            required: true,
+            name: :webhook,
+            type: String,
+            desc: 'The Mattermost webhook. e.g. http://mattermost_host/hooks/...'
+          }
+        ],
+        'teamcity' => [
+          {
+            required: true,
+            name: :teamcity_url,
+            type: String,
+            desc: 'TeamCity root URL like https://teamcity.example.com'
+          },
+          {
+            required: true,
+            name: :build_type,
+            type: String,
+            desc: 'Build configuration ID'
+          },
+          {
+            required: true,
+            name: :username,
+            type: String,
+            desc: 'A user with permissions to trigger a manual build'
+          },
+          {
+            required: true,
+            name: :password,
+            type: String,
+            desc: 'The password of the user'
+          }
+        ]
+      }
+
+      resource :projects do
+        before { authenticate! }
+        before { authorize_admin_project }
+
+        helpers do
+          def service_attributes(service)
+            service.fields.inject([]) do |arr, hash|
+              arr << hash[:name].to_sym
+            end
+          end
+        end
+
+        desc "Delete a service for project"
+        params do
+          requires :service_slug, type: String, values: services.keys, desc: 'The name of the service'
+        end
+        delete ":id/services/:service_slug" do
+          service = user_project.find_or_initialize_service(params[:service_slug].underscore)
+
+          attrs = service_attributes(service).inject({}) do |hash, key|
+            hash.merge!(key => nil)
+          end
+
+          if service.update_attributes(attrs.merge(active: false))
+            status(200)
+            true
+          else
+            render_api_error!('400 Bad Request', 400)
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/lib/api/v3/system_hooks.rb b/lib/api/v3/system_hooks.rb
index 391510b9ee0..5787c06fc12 100644
--- a/lib/api/v3/system_hooks.rb
+++ b/lib/api/v3/system_hooks.rb
@@ -13,6 +13,19 @@ module API
         get do
           present SystemHook.all, with: ::API::Entities::Hook
         end
+
+        desc 'Delete a hook' do
+          success ::API::Entities::Hook
+        end
+        params do
+          requires :id, type: Integer, desc: 'The ID of the system hook'
+        end
+        delete ":id" do
+          hook = SystemHook.find_by(id: params[:id])
+          not_found!('System hook') unless hook
+
+          present hook.destroy, with: ::API::Entities::Hook
+        end
       end
     end
   end
diff --git a/lib/api/v3/tags.rb b/lib/api/v3/tags.rb
index 016e3d86932..6913720d9c5 100644
--- a/lib/api/v3/tags.rb
+++ b/lib/api/v3/tags.rb
@@ -14,6 +14,26 @@ module API
           tags = user_project.repository.tags.sort_by(&:name).reverse
           present tags, with: ::API::Entities::RepoTag, project: user_project
         end
+
+        desc 'Delete a repository tag'
+        params do
+          requires :tag_name, type: String, desc: 'The name of the tag'
+        end
+        delete ":id/repository/tags/:tag_name", requirements: { tag_name: /.+/ } do
+          authorize_push_project
+
+          result = ::Tags::DestroyService.new(user_project, current_user).
+            execute(params[:tag_name])
+
+          if result[:status] == :success
+            status(200)
+            {
+              tag_name: params[:tag_name]
+            }
+          else
+            render_api_error!(result[:message], result[:return_code])
+          end
+        end
       end
     end
   end
diff --git a/lib/api/v3/todos.rb b/lib/api/v3/todos.rb
index 4f9b5fe72a6..e60cb25e57b 100644
--- a/lib/api/v3/todos.rb
+++ b/lib/api/v3/todos.rb
@@ -19,6 +19,8 @@ module API
 
         desc 'Mark all todos as done'
         delete do
+          status(200)
+          
           todos = TodosFinder.new(current_user, params).execute
           TodoService.new.mark_todos_as_done(todos, current_user)
         end
diff --git a/lib/api/v3/triggers.rb b/lib/api/v3/triggers.rb
new file mode 100644
index 00000000000..4051d4bca8d
--- /dev/null
+++ b/lib/api/v3/triggers.rb
@@ -0,0 +1,30 @@
+module API
+  module V3
+    class Triggers < Grape::API
+      include PaginationParams
+
+      params do
+        requires :id, type: String, desc: 'The ID of a project'
+      end
+      resource :projects do
+        desc 'Delete a trigger' do
+          success ::API::Entities::Trigger
+        end
+        params do
+          requires :token, type: String, desc: 'The unique token of trigger'
+        end
+        delete ':id/triggers/:token' do
+          authenticate!
+          authorize! :admin_build, user_project
+
+          trigger = user_project.triggers.find_by(token: params[:token].to_s)
+          return not_found!('Trigger') unless trigger
+
+          trigger.destroy
+
+          present trigger, with: ::API::Entities::Trigger
+        end
+      end
+    end
+  end
+end
diff --git a/lib/api/v3/users.rb b/lib/api/v3/users.rb
index 7838cdc46a7..14f54731730 100644
--- a/lib/api/v3/users.rb
+++ b/lib/api/v3/users.rb
@@ -92,6 +92,25 @@ module API
 
           present paginate(events), with: ::API::V3::Entities::Event
         end
+
+        desc 'Delete an existing SSH key from a specified user. Available only for admins.' do
+          success ::API::Entities::SSHKey
+        end
+        params do
+          requires :id, type: Integer, desc: 'The ID of the user'
+          requires :key_id, type: Integer, desc: 'The ID of the SSH key'
+        end
+        delete ':id/keys/:key_id' do
+          authenticated_as_admin!
+
+          user = User.find_by(id: params[:id])
+          not_found!('User') unless user
+
+          key = user.keys.find_by(id: params[:key_id])
+          not_found!('Key') unless key
+
+          present key.destroy, with: ::API::Entities::SSHKey
+        end
       end
 
       resource :user do
@@ -111,6 +130,19 @@ module API
         get "emails" do
           present current_user.emails, with: ::API::Entities::Email
         end
+
+        desc 'Delete an SSH key from the currently authenticated user' do
+          success ::API::Entities::SSHKey
+        end
+        params do
+          requires :key_id, type: Integer, desc: 'The ID of the SSH key'
+        end
+        delete "keys/:key_id" do
+          key = current_user.keys.find_by(id: params[:key_id])
+          not_found!('Key') unless key
+
+          present key.destroy, with: ::API::Entities::SSHKey
+        end
       end
     end
   end
diff --git a/lib/api/v3/variables.rb b/lib/api/v3/variables.rb
new file mode 100644
index 00000000000..0f55a14fb28
--- /dev/null
+++ b/lib/api/v3/variables.rb
@@ -0,0 +1,29 @@
+module API
+  module V3
+    class Variables < Grape::API
+      include PaginationParams
+
+      before { authenticate! }
+      before { authorize! :admin_build, user_project }
+
+      params do
+        requires :id, type: String, desc: 'The ID of a project'
+      end
+
+      resource :projects do
+        desc 'Delete an existing variable from a project' do
+          success ::API::Entities::Variable
+        end
+        params do
+          requires :key, type: String, desc: 'The key of the variable'
+        end
+        delete ':id/variables/:key' do
+          variable = user_project.variables.find_by(key: params[:key])
+          not_found!('Variable') unless variable
+
+          present variable.destroy, with: ::API::Entities::Variable
+        end
+      end
+    end
+  end
+end
diff --git a/lib/api/variables.rb b/lib/api/variables.rb
index f623b1dfe9f..77e5d54c225 100644
--- a/lib/api/variables.rb
+++ b/lib/api/variables.rb
@@ -1,5 +1,4 @@
 module API
-  # Projects variables API
   class Variables < Grape::API
     include PaginationParams
 
@@ -81,10 +80,9 @@ module API
       end
       delete ':id/variables/:key' do
         variable = user_project.variables.find_by(key: params[:key])
+        not_found!('Variable') unless variable
 
-        return not_found!('Variable') unless variable
-
-        present variable.destroy, with: Entities::Variable
+        variable.destroy
       end
     end
   end
diff --git a/lib/banzai/filter/image_link_filter.rb b/lib/banzai/filter/image_link_filter.rb
index f0fb6084a35..651b55523c0 100644
--- a/lib/banzai/filter/image_link_filter.rb
+++ b/lib/banzai/filter/image_link_filter.rb
@@ -8,11 +8,6 @@ module Banzai
       # of the anchor, and then replace the img with the link-wrapped version.
       def call
         doc.xpath('descendant-or-self::img[not(ancestor::a)]').each do |img|
-          div = doc.document.create_element(
-            'div',
-            class: 'image-container'
-          )
-
           link = doc.document.create_element(
             'a',
             class: 'no-attachment-icon',
@@ -22,9 +17,7 @@ module Banzai
 
           link.children = img.clone
 
-          div.children = link
-
-          img.replace(div)
+          img.replace(link)
         end
 
         doc
diff --git a/lib/bitbucket/error/unauthorized.rb b/lib/bitbucket/error/unauthorized.rb
index 5e2eb57bb0e..efe10542f19 100644
--- a/lib/bitbucket/error/unauthorized.rb
+++ b/lib/bitbucket/error/unauthorized.rb
@@ -1,6 +1,5 @@
 module Bitbucket
   module Error
-    class Unauthorized < StandardError
-    end
+    Unauthorized = Class.new(StandardError)
   end
 end
diff --git a/lib/ci/api/builds.rb b/lib/ci/api/builds.rb
index 8b939663ffd..b51e76d93f2 100644
--- a/lib/ci/api/builds.rb
+++ b/lib/ci/api/builds.rb
@@ -167,7 +167,10 @@ module Ci
 
           build.artifacts_file = artifacts
           build.artifacts_metadata = metadata
-          build.artifacts_expire_in = params['expire_in']
+          build.artifacts_expire_in =
+            params['expire_in'] ||
+            Gitlab::CurrentSettings.current_application_settings
+              .default_artifacts_expire_in
 
           if build.save
             present(build, with: Entities::BuildDetails)
@@ -214,6 +217,7 @@ module Ci
           build = Ci::Build.find_by_id(params[:id])
           authenticate_build!(build)
 
+          status(200)
           build.erase_artifacts!
         end
       end
diff --git a/lib/ci/api/runners.rb b/lib/ci/api/runners.rb
index 2a611a67eaf..c1fd959ef14 100644
--- a/lib/ci/api/runners.rb
+++ b/lib/ci/api/runners.rb
@@ -8,6 +8,8 @@ module Ci
         end
         delete "delete" do
           authenticate_runner!
+
+          status(200)
           Ci::Runner.find_by_token(params[:token]).destroy
         end
 
diff --git a/lib/ci/gitlab_ci_yaml_processor.rb b/lib/ci/gitlab_ci_yaml_processor.rb
index 649ee4d018b..e390919ae1d 100644
--- a/lib/ci/gitlab_ci_yaml_processor.rb
+++ b/lib/ci/gitlab_ci_yaml_processor.rb
@@ -1,6 +1,6 @@
 module Ci
   class GitlabCiYamlProcessor
-    class ValidationError < StandardError; end
+    ValidationError = Class.new(StandardError)
 
     include Gitlab::Ci::Config::Entry::LegacyValidationHelpers
 
diff --git a/lib/extracts_path.rb b/lib/extracts_path.rb
index 9ece84cc469..dd864eea3fa 100644
--- a/lib/extracts_path.rb
+++ b/lib/extracts_path.rb
@@ -2,7 +2,7 @@
 # file path string when combined in a request parameter
 module ExtractsPath
   # Raised when given an invalid file path
-  class InvalidPathError < StandardError; end
+  InvalidPathError = Class.new(StandardError)
 
   # Given a string containing both a Git tree-ish, such as a branch or tag, and
   # a filesystem path joined by forward slashes, attempts to separate the two.
diff --git a/lib/gitlab/access.rb b/lib/gitlab/access.rb
index 3b210eeda9d..8c28009b9c6 100644
--- a/lib/gitlab/access.rb
+++ b/lib/gitlab/access.rb
@@ -5,7 +5,7 @@
 #
 module Gitlab
   module Access
-    class AccessDeniedError < StandardError; end
+    AccessDeniedError = Class.new(StandardError)
 
     NO_ACCESS = 0
     GUEST     = 10
diff --git a/lib/gitlab/auth.rb b/lib/gitlab/auth.rb
index 89db6c3da46..0a5abc92190 100644
--- a/lib/gitlab/auth.rb
+++ b/lib/gitlab/auth.rb
@@ -1,6 +1,6 @@
 module Gitlab
   module Auth
-    class MissingPersonalTokenError < StandardError; end
+    MissingPersonalTokenError = Class.new(StandardError)
 
     SCOPES = [:api, :read_user].freeze
     DEFAULT_SCOPES = [:api].freeze
diff --git a/lib/gitlab/ci/build/artifacts/metadata.rb b/lib/gitlab/ci/build/artifacts/metadata.rb
index cd2e83b4c27..a375ccbece0 100644
--- a/lib/gitlab/ci/build/artifacts/metadata.rb
+++ b/lib/gitlab/ci/build/artifacts/metadata.rb
@@ -6,7 +6,7 @@ module Gitlab
     module Build
       module Artifacts
         class Metadata
-          class ParserError < StandardError; end
+          ParserError = Class.new(StandardError)
 
           VERSION_PATTERN = /^[\w\s]+(\d+\.\d+\.\d+)/
           INVALID_PATH_PATTERN = %r{(^\.?\.?/)|(/\.?\.?/)}
diff --git a/lib/gitlab/ci/config/entry/factory.rb b/lib/gitlab/ci/config/entry/factory.rb
index 9f5e393d191..6be8288748f 100644
--- a/lib/gitlab/ci/config/entry/factory.rb
+++ b/lib/gitlab/ci/config/entry/factory.rb
@@ -6,7 +6,7 @@ module Gitlab
         # Factory class responsible for fabricating entry objects.
         #
         class Factory
-          class InvalidFactory < StandardError; end
+          InvalidFactory = Class.new(StandardError)
 
           def initialize(entry)
             @entry = entry
diff --git a/lib/gitlab/ci/config/entry/node.rb b/lib/gitlab/ci/config/entry/node.rb
index 5eef2868cd6..55a5447ab51 100644
--- a/lib/gitlab/ci/config/entry/node.rb
+++ b/lib/gitlab/ci/config/entry/node.rb
@@ -6,7 +6,7 @@ module Gitlab
         # Base abstract class for each configuration entry node.
         #
         class Node
-          class InvalidError < StandardError; end
+          InvalidError = Class.new(StandardError)
 
           attr_reader :config, :metadata
           attr_accessor :key, :parent, :description
diff --git a/lib/gitlab/ci/config/loader.rb b/lib/gitlab/ci/config/loader.rb
index dbf6eb0edbe..e7d9f6a7761 100644
--- a/lib/gitlab/ci/config/loader.rb
+++ b/lib/gitlab/ci/config/loader.rb
@@ -2,7 +2,7 @@ module Gitlab
   module Ci
     class Config
       class Loader
-        class FormatError < StandardError; end
+        FormatError = Class.new(StandardError)
 
         def initialize(config)
           @config = YAML.safe_load(config, [Symbol], [], true)
diff --git a/lib/gitlab/conflict/file.rb b/lib/gitlab/conflict/file.rb
index d80bc748209..75a213ef752 100644
--- a/lib/gitlab/conflict/file.rb
+++ b/lib/gitlab/conflict/file.rb
@@ -4,8 +4,7 @@ module Gitlab
       include Gitlab::Routing.url_helpers
       include IconsHelper
 
-      class MissingResolution < ResolutionError
-      end
+      MissingResolution = Class.new(ResolutionError)
 
       CONTEXT_LINES = 3
 
diff --git a/lib/gitlab/conflict/file_collection.rb b/lib/gitlab/conflict/file_collection.rb
index fa5bd4649d4..990b719ecfd 100644
--- a/lib/gitlab/conflict/file_collection.rb
+++ b/lib/gitlab/conflict/file_collection.rb
@@ -1,8 +1,7 @@
 module Gitlab
   module Conflict
     class FileCollection
-      class ConflictSideMissing < StandardError
-      end
+      ConflictSideMissing = Class.new(StandardError)
 
       attr_reader :merge_request, :our_commit, :their_commit
 
diff --git a/lib/gitlab/conflict/parser.rb b/lib/gitlab/conflict/parser.rb
index ddd657903fb..d3524c338ee 100644
--- a/lib/gitlab/conflict/parser.rb
+++ b/lib/gitlab/conflict/parser.rb
@@ -1,25 +1,15 @@
 module Gitlab
   module Conflict
     class Parser
-      class UnresolvableError < StandardError
-      end
-
-      class UnmergeableFile < UnresolvableError
-      end
-
-      class UnsupportedEncoding < UnresolvableError
-      end
+      UnresolvableError = Class.new(StandardError)
+      UnmergeableFile = Class.new(UnresolvableError)
+      UnsupportedEncoding = Class.new(UnresolvableError)
 
       # Recoverable errors - the conflict can be resolved in an editor, but not with
       # sections.
-      class ParserError < StandardError
-      end
-
-      class UnexpectedDelimiter < ParserError
-      end
-
-      class MissingEndDelimiter < ParserError
-      end
+      ParserError = Class.new(StandardError)
+      UnexpectedDelimiter = Class.new(ParserError)
+      MissingEndDelimiter = Class.new(ParserError)
 
       def parse(text, our_path:, their_path:, parent_file: nil)
         raise UnmergeableFile if text.blank? # Typically a binary file
diff --git a/lib/gitlab/conflict/resolution_error.rb b/lib/gitlab/conflict/resolution_error.rb
index a0f2006bc24..0b61256b35a 100644
--- a/lib/gitlab/conflict/resolution_error.rb
+++ b/lib/gitlab/conflict/resolution_error.rb
@@ -1,6 +1,5 @@
 module Gitlab
   module Conflict
-    class ResolutionError < StandardError
-    end
+    ResolutionError = Class.new(StandardError)
   end
 end
diff --git a/lib/gitlab/email/receiver.rb b/lib/gitlab/email/receiver.rb
index b64db5d01ae..ec0529b5a4b 100644
--- a/lib/gitlab/email/receiver.rb
+++ b/lib/gitlab/email/receiver.rb
@@ -4,19 +4,19 @@ require_dependency 'gitlab/email/handler'
 # Inspired in great part by Discourse's Email::Receiver
 module Gitlab
   module Email
-    class ProcessingError < StandardError; end
-    class EmailUnparsableError < ProcessingError; end
-    class SentNotificationNotFoundError < ProcessingError; end
-    class ProjectNotFound < ProcessingError; end
-    class EmptyEmailError < ProcessingError; end
-    class AutoGeneratedEmailError < ProcessingError; end
-    class UserNotFoundError < ProcessingError; end
-    class UserBlockedError < ProcessingError; end
-    class UserNotAuthorizedError < ProcessingError; end
-    class NoteableNotFoundError < ProcessingError; end
-    class InvalidNoteError < ProcessingError; end
-    class InvalidIssueError < ProcessingError; end
-    class UnknownIncomingEmail < ProcessingError; end
+    ProcessingError = Class.new(StandardError)
+    EmailUnparsableError = Class.new(ProcessingError)
+    SentNotificationNotFoundError = Class.new(ProcessingError)
+    ProjectNotFound = Class.new(ProcessingError)
+    EmptyEmailError = Class.new(ProcessingError)
+    AutoGeneratedEmailError = Class.new(ProcessingError)
+    UserNotFoundError = Class.new(ProcessingError)
+    UserBlockedError = Class.new(ProcessingError)
+    UserNotAuthorizedError = Class.new(ProcessingError)
+    NoteableNotFoundError = Class.new(ProcessingError)
+    InvalidNoteError = Class.new(ProcessingError)
+    InvalidIssueError = Class.new(ProcessingError)
+    UnknownIncomingEmail = Class.new(ProcessingError)
 
     class Receiver
       def initialize(raw)
diff --git a/lib/gitlab/git/blob.rb b/lib/gitlab/git/blob.rb
index b742d9e1e4b..e56eb0d3beb 100644
--- a/lib/gitlab/git/blob.rb
+++ b/lib/gitlab/git/blob.rb
@@ -93,163 +93,6 @@ module Gitlab
             commit_id: sha,
           )
         end
-
-        # Commit file in repository and return commit sha
-        #
-        # options should contain next structure:
-        #   file: {
-        #     content: 'Lorem ipsum...',
-        #     path: 'documents/story.txt',
-        #     update: true
-        #   },
-        #   author: {
-        #     email: 'user@example.com',
-        #     name: 'Test User',
-        #     time: Time.now
-        #   },
-        #   committer: {
-        #     email: 'user@example.com',
-        #     name: 'Test User',
-        #     time: Time.now
-        #   },
-        #   commit: {
-        #     message: 'Wow such commit',
-        #     branch: 'master',
-        #     update_ref: false
-        #   }
-        #
-        # rubocop:disable Metrics/AbcSize
-        # rubocop:disable Metrics/CyclomaticComplexity
-        # rubocop:disable Metrics/PerceivedComplexity
-        def commit(repository, options, action = :add)
-          file = options[:file]
-          update = file[:update].nil? ? true : file[:update]
-          author = options[:author]
-          committer = options[:committer]
-          commit = options[:commit]
-          repo = repository.rugged
-          ref = commit[:branch]
-          update_ref = commit[:update_ref].nil? ? true : commit[:update_ref]
-          parents = []
-          mode = 0o100644
-
-          unless ref.start_with?('refs/')
-            ref = 'refs/heads/' + ref
-          end
-
-          path_name = Gitlab::Git::PathHelper.normalize_path(file[:path])
-          # Abort if any invalid characters remain (e.g. ../foo)
-          raise Gitlab::Git::Repository::InvalidBlobName.new("Invalid path") if path_name.each_filename.to_a.include?('..')
-
-          filename = path_name.to_s
-          index = repo.index
-
-          unless repo.empty?
-            rugged_ref = repo.references[ref]
-            raise Gitlab::Git::Repository::InvalidRef.new("Invalid branch name") unless rugged_ref
-            last_commit = rugged_ref.target
-            index.read_tree(last_commit.tree)
-            parents = [last_commit]
-          end
-
-          if action == :remove
-            index.remove(filename)
-          else
-            file_entry = index.get(filename)
-
-            if action == :rename
-              old_path_name = Gitlab::Git::PathHelper.normalize_path(file[:previous_path])
-              old_filename = old_path_name.to_s
-              file_entry = index.get(old_filename)
-              index.remove(old_filename) unless file_entry.blank?
-            end
-
-            if file_entry
-              raise Gitlab::Git::Repository::InvalidBlobName.new("Filename already exists; update not allowed") unless update
-
-              # Preserve the current file mode if one is available
-              mode = file_entry[:mode] if file_entry[:mode]
-            end
-
-            content = file[:content]
-            detect = CharlockHolmes::EncodingDetector.new.detect(content) if content
-
-            unless detect && detect[:type] == :binary
-              # When writing to the repo directly as we are doing here,
-              # the `core.autocrlf` config isn't taken into account.
-              content.gsub!("\r\n", "\n") if repository.autocrlf
-            end
-
-            oid = repo.write(content, :blob)
-            index.add(path: filename, oid: oid, mode: mode)
-          end
-
-          opts = {}
-          opts[:tree] = index.write_tree(repo)
-          opts[:author] = author
-          opts[:committer] = committer
-          opts[:message] = commit[:message]
-          opts[:parents] = parents
-          opts[:update_ref] = ref if update_ref
-
-          Rugged::Commit.create(repo, opts)
-        end
-        # rubocop:enable Metrics/AbcSize
-        # rubocop:enable Metrics/CyclomaticComplexity
-        # rubocop:enable Metrics/PerceivedComplexity
-
-        # Remove file from repository and return commit sha
-        #
-        # options should contain next structure:
-        #   file: {
-        #     path: 'documents/story.txt'
-        #   },
-        #   author: {
-        #     email: 'user@example.com',
-        #     name: 'Test User',
-        #     time: Time.now
-        #   },
-        #   committer: {
-        #     email: 'user@example.com',
-        #     name: 'Test User',
-        #     time: Time.now
-        #   },
-        #   commit: {
-        #     message: 'Remove FILENAME',
-        #     branch: 'master'
-        #   }
-        #
-        def remove(repository, options)
-          commit(repository, options, :remove)
-        end
-
-        # Rename file from repository and return commit sha
-        #
-        # options should contain next structure:
-        #   file: {
-        #     previous_path: 'documents/old_story.txt'
-        #     path: 'documents/story.txt'
-        #     content: 'Lorem ipsum...',
-        #     update: true
-        #   },
-        #   author: {
-        #     email: 'user@example.com',
-        #     name: 'Test User',
-        #     time: Time.now
-        #   },
-        #   committer: {
-        #     email: 'user@example.com',
-        #     name: 'Test User',
-        #     time: Time.now
-        #   },
-        #   commit: {
-        #     message: 'Rename FILENAME',
-        #     branch: 'master'
-        #   }
-        #
-        def rename(repository, options)
-          commit(repository, options, :rename)
-        end
       end
 
       def initialize(options)
diff --git a/lib/gitlab/git/diff.rb b/lib/gitlab/git/diff.rb
index d6b3b5705a9..2a017c93f57 100644
--- a/lib/gitlab/git/diff.rb
+++ b/lib/gitlab/git/diff.rb
@@ -2,7 +2,7 @@
 module Gitlab
   module Git
     class Diff
-      class TimeoutError < StandardError; end
+      TimeoutError = Class.new(StandardError)
       include Gitlab::Git::EncodingHelper
 
       # Diff properties
diff --git a/lib/gitlab/git/index.rb b/lib/gitlab/git/index.rb
new file mode 100644
index 00000000000..af1744c9c46
--- /dev/null
+++ b/lib/gitlab/git/index.rb
@@ -0,0 +1,126 @@
+module Gitlab
+  module Git
+    class Index
+      DEFAULT_MODE = 0o100644
+
+      attr_reader :repository, :raw_index
+
+      def initialize(repository)
+        @repository = repository
+        @raw_index = repository.rugged.index
+      end
+
+      delegate :read_tree, :get, to: :raw_index
+
+      def write_tree
+        raw_index.write_tree(repository.rugged)
+      end
+
+      def dir_exists?(path)
+        raw_index.find { |entry| entry[:path].start_with?("#{path}/") }
+      end
+
+      def create(options)
+        options = normalize_options(options)
+
+        file_entry = get(options[:file_path])
+        if file_entry
+          raise Gitlab::Git::Repository::InvalidBlobName.new("Filename already exists")
+        end
+
+        add_blob(options)
+      end
+
+      def create_dir(options)
+        options = normalize_options(options)
+
+        file_entry = get(options[:file_path])
+        if file_entry
+          raise Gitlab::Git::Repository::InvalidBlobName.new("Directory already exists as a file")
+        end
+
+        if dir_exists?(options[:file_path])
+          raise Gitlab::Git::Repository::InvalidBlobName.new("Directory already exists")
+        end
+
+        options = options.dup
+        options[:file_path] += '/.gitkeep'
+        options[:content] = ''
+
+        add_blob(options)
+      end
+
+      def update(options)
+        options = normalize_options(options)
+
+        file_entry = get(options[:file_path])
+        unless file_entry
+          raise Gitlab::Git::Repository::InvalidBlobName.new("File doesn't exist")
+        end
+
+        add_blob(options, mode: file_entry[:mode])
+      end
+
+      def move(options)
+        options = normalize_options(options)
+
+        file_entry = get(options[:previous_path])
+        unless file_entry
+          raise Gitlab::Git::Repository::InvalidBlobName.new("File doesn't exist")
+        end
+
+        raw_index.remove(options[:previous_path])
+
+        add_blob(options, mode: file_entry[:mode])
+      end
+
+      def delete(options)
+        options = normalize_options(options)
+
+        file_entry = get(options[:file_path])
+        unless file_entry
+          raise Gitlab::Git::Repository::InvalidBlobName.new("File doesn't exist")
+        end
+
+        raw_index.remove(options[:file_path])
+      end
+
+      private
+
+      def normalize_options(options)
+        options = options.dup
+        options[:file_path] = normalize_path(options[:file_path]) if options[:file_path]
+        options[:previous_path] = normalize_path(options[:previous_path]) if options[:previous_path]
+        options
+      end
+
+      def normalize_path(path)
+        pathname = Gitlab::Git::PathHelper.normalize_path(path.dup)
+
+        if pathname.each_filename.include?('..')
+          raise Gitlab::Git::Repository::InvalidBlobName.new('Invalid path')
+        end
+
+        pathname.to_s
+      end
+
+      def add_blob(options, mode: nil)
+        content = options[:content]
+        content = Base64.decode64(content) if options[:encoding] == 'base64'
+
+        detect = CharlockHolmes::EncodingDetector.new.detect(content)
+        unless detect && detect[:type] == :binary
+          # When writing to the repo directly as we are doing here,
+          # the `core.autocrlf` config isn't taken into account.
+          content.gsub!("\r\n", "\n") if repository.autocrlf
+        end
+
+        oid = repository.rugged.write(content, :blob)
+
+        raw_index.add(path: options[:file_path], oid: oid, mode: mode || DEFAULT_MODE)
+      rescue Rugged::IndexError => e
+        raise Gitlab::Git::Repository::InvalidBlobName.new(e.message)
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/git/repository.rb b/lib/gitlab/git/repository.rb
index 4b6ad8037ce..0e9b812ffdd 100644
--- a/lib/gitlab/git/repository.rb
+++ b/lib/gitlab/git/repository.rb
@@ -10,9 +10,9 @@ module Gitlab
 
       SEARCH_CONTEXT_LINES = 3
 
-      class NoRepository < StandardError; end
-      class InvalidBlobName < StandardError; end
-      class InvalidRef < StandardError; end
+      NoRepository = Class.new(StandardError)
+      InvalidBlobName = Class.new(StandardError)
+      InvalidRef = Class.new(StandardError)
 
       # Full path to repo
       attr_reader :path
@@ -324,24 +324,30 @@ module Gitlab
       end
 
       def log_by_shell(sha, options)
-        cmd = %W(#{Gitlab.config.git.bin_path} --git-dir=#{path} log)
-        cmd += %W(-n #{options[:limit].to_i})
-        cmd += %w(--format=%H)
-        cmd += %W(--skip=#{options[:offset].to_i})
-        cmd += %w(--follow) if options[:follow]
-        cmd += %w(--no-merges) if options[:skip_merges]
-        cmd += %W(--after=#{options[:after].iso8601}) if options[:after]
-        cmd += %W(--before=#{options[:before].iso8601}) if options[:before]
-        cmd += [sha]
-        cmd += %W(-- #{options[:path]}) if options[:path].present?
-
-        raw_output = IO.popen(cmd) {|io| io.read }
-
-        log = raw_output.lines.map do |c|
-          Rugged::Commit.new(rugged, c.strip)
-        end
+        limit = options[:limit].to_i
+        offset = options[:offset].to_i
+        use_follow_flag = options[:follow] && options[:path].present?
+
+        # We will perform the offset in Ruby because --follow doesn't play well with --skip.
+        # See: https://gitlab.com/gitlab-org/gitlab-ce/issues/3574#note_3040520
+        offset_in_ruby = use_follow_flag && options[:offset].present?
+        limit += offset if offset_in_ruby
+
+        cmd = %W[#{Gitlab.config.git.bin_path} --git-dir=#{path} log]
+        cmd << "--max-count=#{limit}"
+        cmd << '--format=%H'
+        cmd << "--skip=#{offset}" unless offset_in_ruby
+        cmd << '--follow' if use_follow_flag
+        cmd << '--no-merges' if options[:skip_merges]
+        cmd << "--after=#{options[:after].iso8601}" if options[:after]
+        cmd << "--before=#{options[:before].iso8601}" if options[:before]
+        cmd << sha
+        cmd += %W[-- #{options[:path]}] if options[:path].present?
 
-        log.is_a?(Array) ? log : []
+        raw_output = IO.popen(cmd) { |io| io.read }
+        lines = offset_in_ruby ? raw_output.lines.drop(offset) : raw_output.lines
+
+        lines.map! { |c| Rugged::Commit.new(rugged, c.strip) }
       end
 
       def sha_from_ref(ref)
@@ -837,57 +843,6 @@ module Gitlab
         rugged.config['core.autocrlf'] = AUTOCRLF_VALUES.invert[value]
       end
 
-      # Create a new directory with a .gitkeep file. Creates
-      # all required nested directories (i.e. mkdir -p behavior)
-      #
-      # options should contain next structure:
-      #   author: {
-      #     email: 'user@example.com',
-      #     name: 'Test User',
-      #     time: Time.now
-      #   },
-      #   committer: {
-      #     email: 'user@example.com',
-      #     name: 'Test User',
-      #     time: Time.now
-      #   },
-      #   commit: {
-      #     message: 'Wow such commit',
-      #     branch: 'master',
-      #     update_ref: false
-      #   }
-      def mkdir(path, options = {})
-        # Check if this directory exists; if it does, then don't bother
-        # adding .gitkeep file.
-        ref = options[:commit][:branch]
-        path = Gitlab::Git::PathHelper.normalize_path(path).to_s
-        rugged_ref = rugged.ref(ref)
-
-        raise InvalidRef.new("Invalid ref") if rugged_ref.nil?
-
-        target_commit = rugged_ref.target
-
-        raise InvalidRef.new("Invalid target commit") if target_commit.nil?
-
-        entry = tree_entry(target_commit, path)
-
-        if entry
-          if entry[:type] == :blob
-            raise InvalidBlobName.new("Directory already exists as a file")
-          else
-            raise InvalidBlobName.new("Directory already exists")
-          end
-        end
-
-        options[:file] = {
-          content: '',
-          path: "#{path}/.gitkeep",
-          update: true
-        }
-
-        Gitlab::Git::Blob.commit(self, options)
-      end
-
       # Returns result like "git ls-files" , recursive and full file path
       #
       # Ex.
diff --git a/lib/gitlab/gitaly_client.rb b/lib/gitlab/gitaly_client.rb
new file mode 100644
index 00000000000..b981a629fb0
--- /dev/null
+++ b/lib/gitlab/gitaly_client.rb
@@ -0,0 +1,29 @@
+require 'gitaly'
+
+module Gitlab
+  module GitalyClient
+    def self.gitaly_address
+      if Gitlab.config.gitaly.socket_path
+        "unix://#{Gitlab.config.gitaly.socket_path}"
+      end
+    end
+
+    def self.channel
+      return @channel if defined?(@channel)
+
+      @channel =
+        if enabled?
+          # NOTE: Gitaly currently runs on a Unix socket, so permissions are
+          # handled using the file system and no additional authentication is
+          # required (therefore the :this_channel_is_insecure flag)
+          GRPC::Core::Channel.new(gitaly_address, {}, :this_channel_is_insecure)
+        else
+          nil
+        end
+    end
+
+    def self.enabled?
+      gitaly_address.present?
+    end
+  end
+end
diff --git a/lib/gitlab/gitaly_client/notifications.rb b/lib/gitlab/gitaly_client/notifications.rb
new file mode 100644
index 00000000000..b827a56207f
--- /dev/null
+++ b/lib/gitlab/gitaly_client/notifications.rb
@@ -0,0 +1,17 @@
+module Gitlab
+  module GitalyClient
+    class Notifications
+      attr_accessor :stub
+
+      def initialize
+        @stub = Gitaly::Notifications::Stub.new(nil, nil, channel_override: GitalyClient.channel)
+      end
+
+      def post_receive(repo_path)
+        repository = Gitaly::Repository.new(path: repo_path)
+        request = Gitaly::PostReceiveRequest.new(repository: repository)
+        stub.post_receive(request)
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/gon_helper.rb b/lib/gitlab/gon_helper.rb
index 101b1b80c1e..9c384069661 100644
--- a/lib/gitlab/gon_helper.rb
+++ b/lib/gitlab/gon_helper.rb
@@ -1,7 +1,7 @@
 module Gitlab
   module GonHelper
     def add_gon_variables
-      gon.api_version            = API::API.version
+      gon.api_version            = 'v3' # v4 Is not officially released yet, therefore can't be considered as "frozen"
       gon.default_avatar_url     = URI.join(Gitlab.config.gitlab.url, ActionController::Base.helpers.image_path('no_avatar.png')).to_s
       gon.max_file_size          = current_application_settings.max_attachment_size
       gon.relative_url_root      = Gitlab.config.gitlab.relative_url_root
diff --git a/lib/gitlab/import_export.rb b/lib/gitlab/import_export.rb
index f1d1af8eee5..8b327cfc226 100644
--- a/lib/gitlab/import_export.rb
+++ b/lib/gitlab/import_export.rb
@@ -35,7 +35,7 @@ module Gitlab
     end
 
     def export_filename(project:)
-      basename = "#{Time.now.strftime('%Y-%m-%d_%H-%M-%3N')}_#{project.namespace.full_path}_#{project.path}"
+      basename = "#{Time.now.strftime('%Y-%m-%d_%H-%M-%3N')}_#{project.full_path.tr('/', '_')}"
 
       "#{basename[0..FILENAME_LIMIT]}_export.tar.gz"
     end
diff --git a/lib/gitlab/import_export/error.rb b/lib/gitlab/import_export/error.rb
index e341c4d9cf8..788eedf2686 100644
--- a/lib/gitlab/import_export/error.rb
+++ b/lib/gitlab/import_export/error.rb
@@ -1,5 +1,5 @@
 module Gitlab
   module ImportExport
-    class Error < StandardError; end
+    Error = Class.new(StandardError)
   end
 end
diff --git a/lib/gitlab/middleware/webpack_proxy.rb b/lib/gitlab/middleware/webpack_proxy.rb
index 3fe32adeade..6105d165810 100644
--- a/lib/gitlab/middleware/webpack_proxy.rb
+++ b/lib/gitlab/middleware/webpack_proxy.rb
@@ -8,16 +8,16 @@ module Gitlab
         @proxy_host = opts.fetch(:proxy_host, 'localhost')
         @proxy_port = opts.fetch(:proxy_port, 3808)
         @proxy_path = opts[:proxy_path] if opts[:proxy_path]
-        super(app, opts)
+
+        super(app, backend: "http://#{@proxy_host}:#{@proxy_port}", **opts)
       end
 
       def perform_request(env)
-        unless @proxy_path && env['PATH_INFO'].start_with?("/#{@proxy_path}")
-          return @app.call(env)
+        if @proxy_path && env['PATH_INFO'].start_with?("/#{@proxy_path}")
+          super(env)
+        else
+          @app.call(env)
         end
-
-        env['HTTP_HOST'] = "#{@proxy_host}:#{@proxy_port}"
-        super(env)
       end
     end
   end
diff --git a/lib/gitlab/o_auth/user.rb b/lib/gitlab/o_auth/user.rb
index 95d2f559588..fcf51b7fc5b 100644
--- a/lib/gitlab/o_auth/user.rb
+++ b/lib/gitlab/o_auth/user.rb
@@ -5,7 +5,7 @@
 #
 module Gitlab
   module OAuth
-    class SignupDisabledError < StandardError; end
+    SignupDisabledError = Class.new(StandardError)
 
     class User
       attr_accessor :auth_hash, :gl_user
diff --git a/lib/gitlab/regex.rb b/lib/gitlab/regex.rb
index c77fe2d8bdc..5e5f5ff1589 100644
--- a/lib/gitlab/regex.rb
+++ b/lib/gitlab/regex.rb
@@ -5,17 +5,18 @@ module Gitlab
     # The namespace regex is used in Javascript to validate usernames in the "Register" form. However, Javascript
     # does not support the negative lookbehind assertion (?<!) that disallows usernames ending in `.git` and `.atom`.
     # Since this is a non-trivial problem to solve in Javascript (heavily complicate the regex, modify view code to
-    # allow non-regex validatiions, etc), `NAMESPACE_REGEX_STR_SIMPLE` serves as a Javascript-compatible version of
+    # allow non-regex validatiions, etc), `NAMESPACE_REGEX_STR_JS` serves as a Javascript-compatible version of
     # `NAMESPACE_REGEX_STR`, with the negative lookbehind assertion removed. This means that the client-side validation
     # will pass for usernames ending in `.atom` and `.git`, but will be caught by the server-side validation.
     PATH_REGEX_STR = '[a-zA-Z0-9_\.][a-zA-Z0-9_\-\.]*'.freeze
-    NAMESPACE_REGEX_STR_SIMPLE = PATH_REGEX_STR + '[a-zA-Z0-9_\-]|[a-zA-Z0-9_]'.freeze
-    NAMESPACE_REGEX_STR = '(?:' + NAMESPACE_REGEX_STR_SIMPLE + ')(?<!\.git|\.atom)'.freeze
-    PROJECT_REGEX_STR = PATH_REGEX_STR + '(?<!\.git|\.atom)'.freeze
+    NAMESPACE_REGEX_STR_JS = PATH_REGEX_STR + '[a-zA-Z0-9_\-]|[a-zA-Z0-9_]'.freeze
+    NO_SUFFIX_REGEX_STR = '(?<!\.git|\.atom)'.freeze
+    NAMESPACE_REGEX_STR = "(?:#{NAMESPACE_REGEX_STR_JS})#{NO_SUFFIX_REGEX_STR}".freeze
+    PROJECT_REGEX_STR = "(?:#{PATH_REGEX_STR})#{NO_SUFFIX_REGEX_STR}".freeze
 
     # Same as NAMESPACE_REGEX_STR but allows `/` in the path.
     # So `group/subgroup` will match this regex but not NAMESPACE_REGEX_STR
-    NAMESPACE_REF_REGEX_STR = '(?:[a-zA-Z0-9_\.][a-zA-Z0-9_\-\.\/]*[a-zA-Z0-9_\-]|[a-zA-Z0-9_])(?<!\.git|\.atom)'.freeze
+    FULL_NAMESPACE_REGEX_STR = "(?:#{NAMESPACE_REGEX_STR}/)*#{NAMESPACE_REGEX_STR}".freeze
 
     def namespace_regex
       @namespace_regex ||= /\A#{NAMESPACE_REGEX_STR}\z/.freeze
diff --git a/lib/gitlab/route_map.rb b/lib/gitlab/route_map.rb
index 72d00abfcc2..36791fae60f 100644
--- a/lib/gitlab/route_map.rb
+++ b/lib/gitlab/route_map.rb
@@ -1,6 +1,6 @@
 module Gitlab
   class RouteMap
-    class FormatError < StandardError; end
+    FormatError = Class.new(StandardError)
 
     def initialize(data)
       begin
diff --git a/lib/gitlab/serializer/pagination.rb b/lib/gitlab/serializer/pagination.rb
index bf2c0acc729..9c92b83dddc 100644
--- a/lib/gitlab/serializer/pagination.rb
+++ b/lib/gitlab/serializer/pagination.rb
@@ -1,7 +1,7 @@
 module Gitlab
   module Serializer
     class Pagination
-      class InvalidResourceError < StandardError; end
+      InvalidResourceError = Class.new(StandardError)
       include ::API::Helpers::Pagination
 
       def initialize(request, response)
diff --git a/lib/gitlab/shell.rb b/lib/gitlab/shell.rb
index 7374d2bc8b8..da8d8ddb8ed 100644
--- a/lib/gitlab/shell.rb
+++ b/lib/gitlab/shell.rb
@@ -2,7 +2,7 @@ require 'securerandom'
 
 module Gitlab
   class Shell
-    class Error < StandardError; end
+    Error = Class.new(StandardError)
 
     KeyAdder = Struct.new(:io) do
       def add_key(id, key)
diff --git a/lib/gitlab/template/finders/repo_template_finder.rb b/lib/gitlab/template/finders/repo_template_finder.rb
index 22c39436cb2..cb7957e2af9 100644
--- a/lib/gitlab/template/finders/repo_template_finder.rb
+++ b/lib/gitlab/template/finders/repo_template_finder.rb
@@ -4,7 +4,7 @@ module Gitlab
     module Finders
       class RepoTemplateFinder < BaseTemplateFinder
         # Raised when file is not found
-        class FileNotFoundError < StandardError; end
+        FileNotFoundError = Class.new(StandardError)
 
         def initialize(project, base_dir, extension, categories = {})
           @categories     = categories
diff --git a/lib/gitlab/update_path_error.rb b/lib/gitlab/update_path_error.rb
index ce14cc887d0..8947ecfb92e 100644
--- a/lib/gitlab/update_path_error.rb
+++ b/lib/gitlab/update_path_error.rb
@@ -1,3 +1,3 @@
 module Gitlab
-  class UpdatePathError < StandardError; end
+  UpdatePathError = Class.new(StandardError)
 end
diff --git a/lib/mattermost/client.rb b/lib/mattermost/client.rb
index 29b10e2afce..3d60618006c 100644
--- a/lib/mattermost/client.rb
+++ b/lib/mattermost/client.rb
@@ -1,5 +1,5 @@
 module Mattermost
-  class ClientError < Mattermost::Error; end
+  ClientError = Class.new(Mattermost::Error)
 
   class Client
     attr_reader :user
diff --git a/lib/mattermost/error.rb b/lib/mattermost/error.rb
index 014df175be0..dee6deb7974 100644
--- a/lib/mattermost/error.rb
+++ b/lib/mattermost/error.rb
@@ -1,3 +1,3 @@
 module Mattermost
-  class Error < StandardError; end
+  Error = Class.new(StandardError)
 end
diff --git a/lib/mattermost/session.rb b/lib/mattermost/session.rb
index d4b4ba97f8c..688a79c0441 100644
--- a/lib/mattermost/session.rb
+++ b/lib/mattermost/session.rb
@@ -5,7 +5,7 @@ module Mattermost
     end
   end
 
-  class ConnectionError < Mattermost::Error; end
+  ConnectionError = Class.new(Mattermost::Error)
 
   # This class' prime objective is to obtain a session token on a Mattermost
   # instance with SSO configured where this GitLab instance is the provider.