Merge branch 'route-map' into 'master'

Add 'View on [env]' link to blobs and individual files in diffs

See merge request !8867

38 files changed, 815 insertions, 157 deletions

diff --git a/app/controllers/projects/blob_controller.rb b/app/controllers/projects/blob_controller.rb
index 9940263ae24..4c39fe98028 100644
--- a/app/controllers/projects/blob_controller.rb
+++ b/app/controllers/projects/blob_controller.rb
@@ -30,6 +30,8 @@ class Projects::BlobController < Projects::ApplicationController
   end
 
   def show
+    environment_params = @repository.branch_exists?(@ref) ? { ref: @ref } : { commit: @commit }
+    @environment = EnvironmentsFinder.new(@project, current_user, environment_params).execute.last
   end
 
   def edit
diff --git a/app/controllers/projects/commit_controller.rb b/app/controllers/projects/commit_controller.rb
index f880a9862c6..e10d7992db7 100644
--- a/app/controllers/projects/commit_controller.rb
+++ b/app/controllers/projects/commit_controller.rb
@@ -94,6 +94,8 @@ class Projects::CommitController < Projects::ApplicationController
 
     @diffs = commit.diffs(opts)
     @notes_count = commit.notes.count
+    
+    @environment = EnvironmentsFinder.new(@project, current_user, commit: @commit).execute.last
   end
 
   def define_note_vars
diff --git a/app/controllers/projects/compare_controller.rb b/app/controllers/projects/compare_controller.rb
index 321cde255c3..c6651254d70 100644
--- a/app/controllers/projects/compare_controller.rb
+++ b/app/controllers/projects/compare_controller.rb
@@ -57,6 +57,9 @@ class Projects::CompareController < Projects::ApplicationController
 
       @diffs = @compare.diffs(diff_options)
 
+      environment_params = @repository.branch_exists?(@head_ref) ? { ref: @head_ref } : { commit: @commit }
+      @environment = EnvironmentsFinder.new(@project, current_user, environment_params).execute.last
+
       @diff_notes_disabled = true
       @grouped_diff_discussions = {}
     end
diff --git a/app/controllers/projects/environments_controller.rb b/app/controllers/projects/environments_controller.rb
index 77877cd262d..0ec8f5bd64a 100644
--- a/app/controllers/projects/environments_controller.rb
+++ b/app/controllers/projects/environments_controller.rb
@@ -10,7 +10,7 @@ class Projects::EnvironmentsController < Projects::ApplicationController
 
   def index
     @scope = params[:scope]
-    @environments = project.environments
+    @environments = project.environments.includes(:last_deployment)
 
     respond_to do |format|
       format.html
diff --git a/app/controllers/projects/merge_requests_controller.rb b/app/controllers/projects/merge_requests_controller.rb
index 368bd27c91a..3be6e8e1772 100644
--- a/app/controllers/projects/merge_requests_controller.rb
+++ b/app/controllers/projects/merge_requests_controller.rb
@@ -103,6 +103,8 @@ class Projects::MergeRequestsController < Projects::ApplicationController
       end
     end
 
+    @environment = @merge_request.environments_for(current_user).last
+
     respond_to do |format|
       format.html { define_discussion_vars }
       format.json do
@@ -248,7 +250,9 @@ class Projects::MergeRequestsController < Projects::ApplicationController
                  end
         @diff_notes_disabled = true
 
-        render json: { html: view_to_html_string('projects/merge_requests/_new_diffs', diffs: @diffs) }
+        @environment = @merge_request.environments_for(current_user).last
+
+        render json: { html: view_to_html_string('projects/merge_requests/_new_diffs', diffs: @diffs, environment: @environment) }
       end
     end
   end
@@ -447,9 +451,7 @@ class Projects::MergeRequestsController < Projects::ApplicationController
   def ci_environments_status
     environments =
       begin
-        @merge_request.environments.map do |environment|
-          next unless can?(current_user, :read_environment, environment)
-
+        @merge_request.environments_for(current_user).map do |environment|
           project = environment.project
           deployment = environment.first_deployment_for(@merge_request.diff_head_commit)
 
diff --git a/app/finders/environments_finder.rb b/app/finders/environments_finder.rb
new file mode 100644
index 00000000000..a59f8c1efa3
--- /dev/null
+++ b/app/finders/environments_finder.rb
@@ -0,0 +1,55 @@
+class EnvironmentsFinder
+  attr_reader :project, :current_user, :params
+
+  def initialize(project, current_user, params = {})
+    @project, @current_user, @params = project, current_user, params
+  end
+
+  def execute
+    deployments = project.deployments
+    deployments =
+      if ref
+        deployments_query = params[:with_tags] ? 'ref = :ref OR tag IS TRUE' : 'ref = :ref'
+        deployments.where(deployments_query, ref: ref.to_s)
+      elsif commit
+        deployments.where(sha: commit.sha)
+      else
+        deployments.none
+      end
+
+    environment_ids = deployments
+      .group(:environment_id)
+      .select(:environment_id)
+
+    environments = project.environments.available
+      .where(id: environment_ids).order_by_last_deployed_at.to_a
+
+    environments.select! do |environment|
+      Ability.allowed?(current_user, :read_environment, environment)
+    end
+
+    if ref && commit
+      environments.select! do |environment|
+        environment.includes_commit?(commit)
+      end
+    end
+
+    if ref && params[:recently_updated]
+      environments.select! do |environment|
+        environment.recently_updated_on_branch?(ref)
+      end
+    end
+
+    environments
+  end
+
+  private
+
+  def ref
+    params[:ref].try(:to_s)
+  end
+
+  def commit
+    params[:commit]
+  end
+end
diff --git a/app/helpers/commits_helper.rb b/app/helpers/commits_helper.rb
index 6dcb624c4da..8aad39e148b 100644
--- a/app/helpers/commits_helper.rb
+++ b/app/helpers/commits_helper.rb
@@ -194,7 +194,7 @@ module CommitsHelper
     end
   end
 
-  def view_file_btn(commit_sha, diff_new_path, project)
+  def view_file_button(commit_sha, diff_new_path, project)
     link_to(
       namespace_project_blob_path(project.namespace, project,
                                   tree_join(commit_sha, diff_new_path)),
@@ -205,6 +205,17 @@ module CommitsHelper
     end
   end
 
+  def view_on_environment_button(commit_sha, diff_new_path, environment)
+    return unless environment && commit_sha
+
+    external_url = environment.external_url_for(diff_new_path, commit_sha)
+    return unless external_url
+
+    link_to(external_url, class: 'btn btn-file-option has-tooltip', target: '_blank', title: "View on #{environment.formatted_external_url}", data: { container: 'body' }) do
+      icon('external-link')
+    end
+  end
+
   def truncate_sha(sha)
     Commit.truncate_sha(sha)
   end
diff --git a/app/models/ci/build.rb b/app/models/ci/build.rb
index 3c1a1ae5933..5213ea9d02b 100644
--- a/app/models/ci/build.rb
+++ b/app/models/ci/build.rb
@@ -9,6 +9,7 @@ module Ci
     belongs_to :erased_by, class_name: 'User'
 
     has_many :deployments, as: :deployable
+    has_one :last_deployment, -> { order('deployments.id DESC') }, as: :deployable, class_name: 'Deployment'
 
     # The "environment" field for builds is a String, and is the unexpanded name
     def persisted_environment
@@ -183,10 +184,6 @@ module Ci
       success? && !last_deployment.try(:last?)
     end
 
-    def last_deployment
-      deployments.last
-    end
-
     def depends_on_builds
       # Get builds of the same type
       latest_builds = self.pipeline.builds.latest
diff --git a/app/models/ci/pipeline.rb b/app/models/ci/pipeline.rb
index fab8497ec7d..bbc358adb83 100644
--- a/app/models/ci/pipeline.rb
+++ b/app/models/ci/pipeline.rb
@@ -283,13 +283,7 @@ module Ci
     def ci_yaml_file
       return @ci_yaml_file if defined?(@ci_yaml_file)
 
-      @ci_yaml_file ||= begin
-        blob = project.repository.blob_at(sha, '.gitlab-ci.yml')
-        blob.load_all_data!(project.repository)
-        blob.data
-      rescue
-        nil
-      end
+      @ci_yaml_file = project.repository.gitlab_ci_yml_for(sha) rescue nil
     end
 
     def has_yaml_errors?
diff --git a/app/models/environment.rb b/app/models/environment.rb
index 13c4630c565..803060b3979 100644
--- a/app/models/environment.rb
+++ b/app/models/environment.rb
@@ -6,7 +6,8 @@ class Environment < ActiveRecord::Base
 
   belongs_to :project, required: true, validate: true
 
-  has_many :deployments
+  has_many :deployments, dependent: :destroy
+  has_one :last_deployment, -> { order('deployments.id DESC') }, class_name: 'Deployment'
 
   before_validation :nullify_external_url
   before_validation :generate_slug, if: ->(env) { env.slug.blank? }
@@ -37,6 +38,13 @@ class Environment < ActiveRecord::Base
 
   scope :available, -> { with_state(:available) }
   scope :stopped, -> { with_state(:stopped) }
+  scope :order_by_last_deployed_at, -> do
+    max_deployment_id_sql =
+      Deployment.select(Deployment.arel_table[:id].maximum).
+      where(Deployment.arel_table[:environment_id].eq(arel_table[:id])).
+      to_sql
+    order(Gitlab::Database.nulls_first_order("(#{max_deployment_id_sql})", 'ASC'))
+  end
 
   state_machine :state, initial: :available do
     event :start do
@@ -62,10 +70,6 @@ class Environment < ActiveRecord::Base
     ref.to_s == last_deployment.try(:ref)
   end
 
-  def last_deployment
-    deployments.last
-  end
-
   def nullify_external_url
     self.external_url = nil if self.external_url.blank?
   end
@@ -87,6 +91,10 @@ class Environment < ActiveRecord::Base
     last_deployment.includes_commit?(commit)
   end
 
+  def last_deployed_at
+    last_deployment.try(:created_at)
+  end
+
   def update_merge_request_metrics?
     (environment_type || name) == "production"
   end
@@ -171,6 +179,15 @@ class Environment < ActiveRecord::Base
     self.slug = slugified
   end
 
+  def external_url_for(path, commit_sha)
+    return unless self.external_url
+
+    public_path = project.public_path_for_source_path(path, commit_sha)
+    return unless public_path
+
+    [external_url, public_path].join('/')
+  end
+
   private
 
   # Slugifying a name may remove the uniqueness guarantee afforded by it being
diff --git a/app/models/merge_request.rb b/app/models/merge_request.rb
index 082adcafcc8..43085f69105 100644
--- a/app/models/merge_request.rb
+++ b/app/models/merge_request.rb
@@ -715,18 +715,22 @@ class MergeRequest < ActiveRecord::Base
     !head_pipeline || head_pipeline.success? || head_pipeline.skipped?
   end
 
-  def environments
+  def environments_for(current_user)
     return [] unless diff_head_commit
 
-    @environments ||= begin
-      target_envs = target_project.environments_for(
-        target_branch, commit: diff_head_commit, with_tags: true)
+    @environments ||= Hash.new do |h, current_user|
+      envs = EnvironmentsFinder.new(target_project, current_user,
+        ref: target_branch, commit: diff_head_commit, with_tags: true).execute
 
-      source_envs = source_project.environments_for(
-        source_branch, commit: diff_head_commit) if source_project
+      if source_project
+        envs.concat EnvironmentsFinder.new(source_project, current_user,
+          ref: source_branch, commit: diff_head_commit).execute
+      end
 
-      (target_envs.to_a + source_envs.to_a).uniq
+      h[current_user] = envs.uniq
     end
+
+    @environments[current_user]
   end
 
   def state_human_name
diff --git a/app/models/project.rb b/app/models/project.rb
index 7c5fdad5122..b45f22d94d9 100644
--- a/app/models/project.rb
+++ b/app/models/project.rb
@@ -1306,28 +1306,26 @@ class Project < ActiveRecord::Base
     Gitlab::Redis.with { |redis| redis.del(pushes_since_gc_redis_key) }
   end
 
-  def environments_for(ref, commit: nil, with_tags: false)
-    deployments_query = with_tags ? 'ref = ? OR tag IS TRUE' : 'ref = ?'
-
-    environment_ids = deployments
-      .where(deployments_query, ref.to_s)
-      .group(:environment_id)
-      .select(:environment_id)
-
-    environments_found = environments.available
-      .where(id: environment_ids).to_a
-
-    return environments_found unless commit
-
-    environments_found.select do |environment|
-      environment.includes_commit?(commit)
+  def route_map_for(commit_sha)
+    @route_maps_by_commit ||= Hash.new do |h, sha|
+      h[sha] = begin
+        data = repository.route_map_for(sha)
+        next unless data
+
+        Gitlab::RouteMap.new(data)
+      rescue Gitlab::RouteMap::FormatError
+        nil
+      end
     end
+
+    @route_maps_by_commit[commit_sha]
   end
 
-  def environments_recently_updated_on_branch(branch)
-    environments_for(branch).select do |environment|
-      environment.recently_updated_on_branch?(branch)
-    end
+  def public_path_for_source_path(path, commit_sha)
+    map = route_map_for(commit_sha)
+    return unless map
+
+    map.public_path_for_source_path(path)
   end
 
   private
diff --git a/app/models/repository.rb b/app/models/repository.rb
index 7cf09c52bf4..d2d92a064a4 100644
--- a/app/models/repository.rb
+++ b/app/models/repository.rb
@@ -464,6 +464,8 @@ class Repository
     unless Gitlab::Git.blank_ref?(sha)
       Blob.decorate(Gitlab::Git::Blob.find(self, sha, path))
     end
+  rescue Gitlab::Git::Repository::NoRepository
+    nil
   end
 
   def blob_by_oid(oid)
@@ -1160,6 +1162,14 @@ class Repository
     end
   end
 
+  def route_map_for(sha)
+    blob_data_at(sha, '.gitlab/route-map.yml')
+  end
+
+  def gitlab_ci_yml_for(sha)
+    blob_data_at(sha, '.gitlab-ci.yml')
+  end
+
   protected
 
   def tree_entry_at(branch_name, path)
@@ -1186,6 +1196,14 @@ class Repository
 
   private
 
+  def blob_data_at(sha, path)
+    blob = blob_at(sha, path)
+    return unless blob
+
+    blob.load_all_data!(self)
+    blob.data
+  end
+
   def git_action(index, action)
     path = normalize_path(action[:file_path])
 
diff --git a/app/services/ci/stop_environments_service.rb b/app/services/ci/stop_environments_service.rb
index a51310c3967..42c72aba7dd 100644
--- a/app/services/ci/stop_environments_service.rb
+++ b/app/services/ci/stop_environments_service.rb
@@ -21,8 +21,8 @@ module Ci
     end
 
     def environments
-      @environments ||= project
-        .environments_recently_updated_on_branch(@ref)
+      @environments ||=
+        EnvironmentsFinder.new(project, current_user, ref: @ref, recently_updated: true).execute
     end
   end
 end
diff --git a/app/views/projects/blob/_actions.html.haml b/app/views/projects/blob/_actions.html.haml
index 26531f0b1a6..7b9cfbbd067 100644
--- a/app/views/projects/blob/_actions.html.haml
+++ b/app/views/projects/blob/_actions.html.haml
@@ -1,3 +1,6 @@
+.btn-group
+  = view_on_environment_button(@commit.sha, @path, @environment) if @environment
+
 .btn-group.tree-btn-group
   = link_to 'Raw', namespace_project_raw_path(@project.namespace, @project, @id),
       class: 'btn btn-sm', target: '_blank'
diff --git a/app/views/projects/commit/show.html.haml b/app/views/projects/commit/show.html.haml
index 7afd3d80ef5..d5fc283aa8d 100644
--- a/app/views/projects/commit/show.html.haml
+++ b/app/views/projects/commit/show.html.haml
@@ -9,7 +9,7 @@
     = render "ci_menu"
   - else
     .block-connector
-  = render "projects/diffs/diffs", diffs: @diffs
+  = render "projects/diffs/diffs", diffs: @diffs, environment: @environment
   = render "projects/notes/notes_with_form"
   - if can_collaborate_with_project?
     - %w(revert cherry-pick).each do |type|
diff --git a/app/views/projects/compare/show.html.haml b/app/views/projects/compare/show.html.haml
index 9c8f58d4aea..0dfc9fe20ed 100644
--- a/app/views/projects/compare/show.html.haml
+++ b/app/views/projects/compare/show.html.haml
@@ -8,7 +8,7 @@
 
   - if @commits.present?
     = render "projects/commits/commit_list"
-    = render "projects/diffs/diffs", diffs: @diffs
+    = render "projects/diffs/diffs", diffs: @diffs, environment: @environment
   - else
     .light-well
       .center
diff --git a/app/views/projects/diffs/_diffs.html.haml b/app/views/projects/diffs/_diffs.html.haml
index 58c20e225c6..4b49bed835f 100644
--- a/app/views/projects/diffs/_diffs.html.haml
+++ b/app/views/projects/diffs/_diffs.html.haml
@@ -1,3 +1,4 @@
+- environment = local_assigns.fetch(:environment, nil)
 - show_whitespace_toggle = local_assigns.fetch(:show_whitespace_toggle, true)
 - can_create_note = !@diff_notes_disabled && can?(current_user, :create_note, diffs.project)
 - diff_files = diffs.diff_files
@@ -30,4 +31,4 @@
     - file_hash = hexdigest(diff_file.file_path)
 
     = render 'projects/diffs/file', file_hash: file_hash, project: diffs.project,
-      diff_file: diff_file, diff_commit: diff_commit, blob: blob
+      diff_file: diff_file, diff_commit: diff_commit, blob: blob, environment: environment
diff --git a/app/views/projects/diffs/_file.html.haml b/app/views/projects/diffs/_file.html.haml
index fc478ccc995..75885badac9 100644
--- a/app/views/projects/diffs/_file.html.haml
+++ b/app/views/projects/diffs/_file.html.haml
@@ -1,3 +1,4 @@
+- environment = local_assigns.fetch(:environment, nil)
 .diff-file.file-holder{ id: file_hash, data: diff_file_html_data(project, diff_file.file_path, diff_commit.id) }
   .file-title
     = render "projects/diffs/file_header", diff_file: diff_file, blob: blob, diff_commit: diff_commit, project: project, url: "##{file_hash}"
@@ -13,6 +14,7 @@
             = edit_blob_link(@merge_request.source_project, @merge_request.source_branch, diff_file.new_path,
                              blob: blob, link_opts: link_opts)
 
-        = view_file_btn(diff_commit.id, diff_file.new_path, project)
+        = view_file_button(diff_commit.id, diff_file.new_path, project)
+        = view_on_environment_button(diff_commit.id, diff_file.new_path, environment) if environment
 
   = render 'projects/diffs/content', diff_file: diff_file, diff_commit: diff_commit, blob: blob, project: project
diff --git a/app/views/projects/merge_requests/_new_diffs.html.haml b/app/views/projects/merge_requests/_new_diffs.html.haml
index 74367ab9b7b..627fc4e9671 100644
--- a/app/views/projects/merge_requests/_new_diffs.html.haml
+++ b/app/views/projects/merge_requests/_new_diffs.html.haml
@@ -1 +1 @@
-= render "projects/diffs/diffs", diffs: @diffs, show_whitespace_toggle: false
+= render "projects/diffs/diffs", diffs: @diffs, environment: @environment, show_whitespace_toggle: false
diff --git a/app/views/projects/merge_requests/show/_diffs.html.haml b/app/views/projects/merge_requests/show/_diffs.html.haml
index 5f048d04b27..7f0913ea516 100644
--- a/app/views/projects/merge_requests/show/_diffs.html.haml
+++ b/app/views/projects/merge_requests/show/_diffs.html.haml
@@ -1,5 +1,5 @@
 - if @merge_request_diff.collected? || @merge_request_diff.overflow?
   = render 'projects/merge_requests/show/versions'
-  = render "projects/diffs/diffs", diffs: @diffs
+  = render "projects/diffs/diffs", diffs: @diffs, environment: @environment
 - elsif @merge_request_diff.empty?
   .nothing-here-block Nothing to merge from #{@merge_request.source_branch} into #{@merge_request.target_branch}
diff --git a/changelogs/unreleased/route-map.yml b/changelogs/unreleased/route-map.yml
new file mode 100644
index 00000000000..9b6df0c54af
--- /dev/null
+++ b/changelogs/unreleased/route-map.yml
@@ -0,0 +1,4 @@
+---
+title: Add 'View on [env]' link to blobs and individual files in diffs
+merge_request: 8867
+author:
diff --git a/doc/ci/environments.md b/doc/ci/environments.md
index 579135c2052..f00cc854b05 100644
--- a/doc/ci/environments.md
+++ b/doc/ci/environments.md
@@ -442,6 +442,45 @@ and/or `production`) you can see this information in the merge request itself.
 
 ![Environment URLs in merge request](img/environments_link_url_mr.png)
 
+### Go directly from source files to public pages on the environment
+
+> Introduced in GitLab 8.17.
+
+To go one step further, we can specify a Route Map to get GitLab to show us "View on [environment URL]" buttons to go directly from a file to that file's representation on the deployed website. It will be exposed in a few places:
+
+| In the diff for a merge request, comparison or commit | In the file view |
+| ------ | ------ |
+| !["View on env" button in merge request diff](img/view_on_env_mr.png) | !["View on env" button in file view](img/view_on_env_blob.png) |
+
+To get this to work, you need to tell GitLab how the paths of files in your repository map to paths of pages on your website, using a Route Map.
+
+A Route Map is a file inside the repository at `.gitlab/route-map.yml`, which contains a YAML array that maps `source` paths (in the repository) to `public` paths (on the website).
+
+This is an example of a route map for [Middleman](https://middlemanapp.com) static websites like [http://about.gitlab.com](https://gitlab.com/gitlab-com/www-gitlab-com):
+
+```yaml
+# Blogposts
+- source: /source\/posts\/([0-9]{4})-([0-9]{2})-([0-9]{2})-(.+?)\..*/ # source/posts/2017-01-30-around-the-world-in-6-releases.html.md.erb
+  public: '\1/\2/\3/\4/' # 2017/01/30/around-the-world-in-6-releases/
+
+# HTML files
+- source: /source\/(.+?\.html).*/ # source/index.html.haml
+  public: '\1' # index.html
+
+# Other files
+- source: /source\/(.*)/ # source/images/blogimages/around-the-world-in-6-releases-cover.png
+  public: '\1' # images/blogimages/around-the-world-in-6-releases-cover.png
+```
+
+Mappings are defined as entries in the root YAML array, and are identified by a `-` prefix. Within an entry, we have a hash map with two keys:
+
+- `source`: a regular expression, starting and ending with `/`. Can include capture groups denoted by `()` that can be referred to in the `public` path. Slashes (`/`) can, but don't have to be, escaped as `\/`.
+- `public`: a string, starting and ending with `'`. Can include `\N` expressions to refer to capture groups in the `source` regular expression in order of their occurence, starting with `\1`.
+
+The public path for a source path is determined by finding the first `source` expression that matches it, and returning the corresponding `public` path, replacing the `\N` expressions with the values of the `()` capture groups.
+
+In the example above, the fact that mappings are evaluated in order of their definition is used to ensure that `source/index.html.haml` will match `/source\/(.+?\.html).*/` instead of `/source\/(.*)/`, and will result in a public path of `index.html`, instead of `index.html.haml`.
+
 ---
 
 We now have a full development cycle, where our app is tested, built, deployed
diff --git a/doc/ci/img/view_on_env_blob.png b/doc/ci/img/view_on_env_blob.png
new file mode 100644
index 00000000000..f4fe99046f0
--- /dev/null
+++ b/doc/ci/img/view_on_env_blob.png
diff --git a/doc/ci/img/view_on_env_mr.png b/doc/ci/img/view_on_env_mr.png
new file mode 100644
index 00000000000..47ddb40bdc1
--- /dev/null
+++ b/doc/ci/img/view_on_env_mr.png
diff --git a/lib/gitlab/database.rb b/lib/gitlab/database.rb
index 55b8f888d53..dc2537d36aa 100644
--- a/lib/gitlab/database.rb
+++ b/lib/gitlab/database.rb
@@ -35,6 +35,20 @@ module Gitlab
       order
     end
 
+    def self.nulls_first_order(field, direction = 'ASC')
+      order = "#{field} #{direction}"
+
+      if Gitlab::Database.postgresql?
+        order << ' NULLS FIRST'
+      else
+        # `field IS NULL` will be `0` for non-NULL columns and `1` for NULL
+        # columns. In the (default) ascending order, `0` comes first.
+        order.prepend("#{field} IS NULL, ") if direction == 'DESC'
+      end
+
+      order
+    end
+
     def self.random
       Gitlab::Database.postgresql? ? "RANDOM()" : "RAND()"
     end
diff --git a/lib/gitlab/route_map.rb b/lib/gitlab/route_map.rb
new file mode 100644
index 00000000000..89985d90c10
--- /dev/null
+++ b/lib/gitlab/route_map.rb
@@ -0,0 +1,52 @@
+module Gitlab
+  class RouteMap
+    class FormatError < StandardError; end
+
+    def initialize(data)
+      begin
+        entries = YAML.safe_load(data)
+      rescue
+        raise FormatError, 'Route map needs to be valid YAML'
+      end
+
+      raise FormatError, 'Route map needs to be an array' unless entries.is_a?(Array)
+
+      @map = entries.map { |entry| parse_entry(entry) }
+    end
+
+    def public_path_for_source_path(path)
+      mapping = @map.find { |mapping| path =~ mapping[:source] }
+      return unless mapping
+
+      path.sub(mapping[:source], mapping[:public])
+    end
+
+    private
+
+    def parse_entry(entry)
+      raise FormatError, 'Route map entry needs to be a hash' unless entry.is_a?(Hash)
+      raise FormatError, 'Route map entry requires a source key' unless entry.has_key?('source')
+      raise FormatError, 'Route map entry requires a public key' unless entry.has_key?('public')
+
+      source_regexp = entry['source']
+      public_path = entry['public']
+
+      unless source_regexp.start_with?('/') && source_regexp.end_with?('/')
+        raise FormatError, 'Route map entry source needs to start and end in a slash (/)'
+      end
+
+      source_regexp = source_regexp[1...-1].gsub('\/', '/')
+
+      begin
+        source_regexp = Regexp.new("^#{source_regexp}$")
+      rescue RegexpError => e
+        raise FormatError, "Route map entry source needs to be a valid regular expression: #{e}"
+      end
+
+      {
+        source: source_regexp,
+        public: public_path
+      }
+    end
+  end
+end
diff --git a/spec/features/projects/commits/cherry_pick_spec.rb b/spec/features/projects/commit/cherry_pick_spec.rb
index 7baf7913424..7baf7913424 100644
--- a/spec/features/projects/commits/cherry_pick_spec.rb
+++ b/spec/features/projects/commit/cherry_pick_spec.rb
diff --git a/spec/features/compare_spec.rb b/spec/features/projects/compare_spec.rb
index 43eb4000e58..43eb4000e58 100644
--- a/spec/features/compare_spec.rb
+++ b/spec/features/projects/compare_spec.rb
diff --git a/spec/features/projects/view_on_env_spec.rb b/spec/features/projects/view_on_env_spec.rb
new file mode 100644
index 00000000000..ce5c5f21167
--- /dev/null
+++ b/spec/features/projects/view_on_env_spec.rb
@@ -0,0 +1,140 @@
+require 'spec_helper'
+
+describe 'View on environment', js: true do
+  include WaitForAjax
+
+  let(:branch_name) { 'feature' }
+  let(:file_path) { 'files/ruby/feature.rb' }
+  let(:project) { create(:project, :repository) }
+  let(:user) { project.creator }
+
+  before do
+    project.add_master(user)
+  end
+
+  context 'when the branch has a route map' do
+    let(:route_map) do
+      <<-MAP.strip_heredoc
+      - source: /files/(.*)\\..*/
+        public: '\\1'
+      MAP
+    end
+
+    before do
+      Files::CreateService.new(
+        project,
+        user,
+        start_branch: branch_name,
+        target_branch: branch_name,
+        commit_message: "Add .gitlab/route-map.yml",
+        file_path: '.gitlab/route-map.yml',
+        file_content: route_map
+      ).execute
+
+      # Update the file so that we still have a commit that will have a file on the environment
+      Files::UpdateService.new(
+        project,
+        user,
+        start_branch: branch_name,
+        target_branch: branch_name,
+        commit_message: "Update feature",
+        file_path: file_path,
+        file_content: "# Noop"
+      ).execute
+    end
+
+    context 'and an active deployment' do
+      let(:sha) { project.commit(branch_name).sha }
+      let(:environment) { create(:environment, project: project, name: 'review/feature', external_url: 'http://feature.review.example.com') }
+      let!(:deployment) { create(:deployment, environment: environment, ref: branch_name, sha: sha) }
+
+      context 'when visiting the diff of a merge request for the branch' do
+        let(:merge_request) { create(:merge_request, :simple, source_project: project, source_branch: branch_name) }
+
+        before do
+          login_as(user)
+
+          visit diffs_namespace_project_merge_request_path(project.namespace, project, merge_request)
+
+          wait_for_ajax
+        end
+
+        it 'has a "View on env" button' do
+          within '.diffs' do
+            expect(page).to have_link('View on feature.review.example.com', href: 'http://feature.review.example.com/ruby/feature')
+          end
+        end
+      end
+
+      context 'when visiting a comparison for the branch' do
+        before do
+          login_as(user)
+
+          visit namespace_project_compare_path(project.namespace, project, from: 'master', to: branch_name)
+
+          wait_for_ajax
+        end
+
+        it 'has a "View on env" button' do
+          expect(page).to have_link('View on feature.review.example.com', href: 'http://feature.review.example.com/ruby/feature')
+        end
+      end
+
+      context 'when visiting a comparison for the commit' do
+        before do
+          login_as(user)
+
+          visit namespace_project_compare_path(project.namespace, project, from: 'master', to: sha)
+
+          wait_for_ajax
+        end
+
+        it 'has a "View on env" button' do
+          expect(page).to have_link('View on feature.review.example.com', href: 'http://feature.review.example.com/ruby/feature')
+        end
+      end
+
+      context 'when visiting a blob on the branch' do
+        before do
+          login_as(user)
+
+          visit namespace_project_blob_path(project.namespace, project, File.join(branch_name, file_path))
+
+          wait_for_ajax
+        end
+
+        it 'has a "View on env" button' do
+          expect(page).to have_link('View on feature.review.example.com', href: 'http://feature.review.example.com/ruby/feature')
+        end
+      end
+
+      context 'when visiting a blob on the commit' do
+        before do
+          login_as(user)
+
+          visit namespace_project_blob_path(project.namespace, project, File.join(sha, file_path))
+
+          wait_for_ajax
+        end
+
+        it 'has a "View on env" button' do
+          expect(page).to have_link('View on feature.review.example.com', href: 'http://feature.review.example.com/ruby/feature')
+        end
+      end
+
+      context 'when visiting the commit' do
+        before do
+          login_as(user)
+
+          visit namespace_project_commit_path(project.namespace, project, sha)
+
+          wait_for_ajax
+        end
+
+        it 'has a "View on env" button' do
+          expect(page).to have_link('View on feature.review.example.com', href: 'http://feature.review.example.com/ruby/feature')
+        end
+      end
+    end
+  end
+end
diff --git a/spec/finders/environments_finder_spec.rb b/spec/finders/environments_finder_spec.rb
new file mode 100644
index 00000000000..0c063f6d5ee
--- /dev/null
+++ b/spec/finders/environments_finder_spec.rb
@@ -0,0 +1,110 @@
+require 'spec_helper'
+
+describe EnvironmentsFinder do
+  describe '#execute' do
+    let(:project) { create(:project, :repository) }
+    let(:user) { project.creator }
+    let(:environment) { create(:environment, project: project) }
+
+    before do
+      project.add_master(user)
+    end
+
+    context 'tagged deployment' do
+      before do
+        create(:deployment, environment: environment, ref: '1.0', tag: true, sha: project.commit.id)
+      end
+
+      it 'returns environment when with_tags is set' do
+        expect(described_class.new(project, user, ref: 'master', commit: project.commit, with_tags: true).execute)
+          .to contain_exactly(environment)
+      end
+
+      it 'does not return environment when no with_tags is set' do
+        expect(described_class.new(project, user, ref: 'master', commit: project.commit).execute)
+          .to be_empty
+      end
+
+      it 'does not return environment when commit is not part of deployment' do
+        expect(described_class.new(project, user, ref: 'master', commit: project.commit('feature')).execute)
+          .to be_empty
+      end
+    end
+
+    context 'branch deployment' do
+      before do
+        create(:deployment, environment: environment, ref: 'master', sha: project.commit.id)
+      end
+
+      it 'returns environment when ref is set' do
+        expect(described_class.new(project, user, ref: 'master', commit: project.commit).execute)
+          .to contain_exactly(environment)
+      end
+
+      it 'does not environment when ref is different' do
+        expect(described_class.new(project, user, ref: 'feature', commit: project.commit).execute)
+          .to be_empty
+      end
+
+      it 'does not return environment when commit is not part of deployment' do
+        expect(described_class.new(project, user, ref: 'master', commit: project.commit('feature')).execute)
+          .to be_empty
+      end
+
+      it 'returns environment when commit constraint is not set' do
+        expect(described_class.new(project, user, ref: 'master').execute)
+          .to contain_exactly(environment)
+      end
+    end
+
+    context 'commit deployment' do
+      before do
+        create(:deployment, environment: environment, ref: 'master', sha: project.commit.id)
+      end
+
+      it 'returns environment' do
+        expect(described_class.new(project, user, commit: project.commit).execute)
+          .to contain_exactly(environment)
+      end
+    end
+
+    context 'recently updated' do
+      context 'when last deployment to environment is the most recent one' do
+        before do
+          create(:deployment, environment: environment, ref: 'feature')
+        end
+
+        it 'finds recently updated environment' do
+          expect(described_class.new(project, user, ref: 'feature', recently_updated: true).execute)
+            .to contain_exactly(environment)
+        end
+      end
+
+      context 'when last deployment to environment is not the most recent' do
+        before do
+          create(:deployment, environment: environment, ref: 'feature')
+          create(:deployment, environment: environment, ref: 'master')
+        end
+
+        it 'does not find environment' do
+          expect(described_class.new(project, user, ref: 'feature', recently_updated: true).execute)
+            .to be_empty
+        end
+      end
+
+      context 'when there are two environments that deploy to the same branch' do
+        let(:second_environment) { create(:environment, project: project) }
+
+        before do
+          create(:deployment, environment: environment, ref: 'feature')
+          create(:deployment, environment: second_environment, ref: 'feature')
+        end
+
+        it 'finds both environments' do
+          expect(described_class.new(project, user, ref: 'feature', recently_updated: true).execute)
+            .to contain_exactly(environment, second_environment)
+        end
+      end
+    end
+  end
+end
diff --git a/spec/helpers/commits_helper_spec.rb b/spec/helpers/commits_helper_spec.rb
index 727c25ff529..a2c008790f9 100644
--- a/spec/helpers/commits_helper_spec.rb
+++ b/spec/helpers/commits_helper_spec.rb
@@ -26,4 +26,23 @@ describe CommitsHelper do
         not_to include('onmouseover="alert(1)"')
     end
   end
+
+  describe '#view_on_environment_button' do
+    let(:project) { create(:empty_project) }
+    let(:environment) { create(:environment, external_url: 'http://example.com') }
+    let(:path) { 'source/file.html' }
+    let(:sha) { RepoHelpers.sample_commit.id }
+
+    before do
+      allow(environment).to receive(:external_url_for).with(path, sha).and_return('http://example.com/file.html')
+    end
+
+    it 'returns a link tag linking to the file in the environment' do
+      html = helper.view_on_environment_button(sha, path, environment)
+      node = Nokogiri::HTML.parse(html).at_css('a')
+
+      expect(node[:title]).to eq('View on example.com')
+      expect(node[:href]).to eq('http://example.com/file.html')
+    end
+  end
 end
diff --git a/spec/lib/gitlab/database_spec.rb b/spec/lib/gitlab/database_spec.rb
index 3031559c613..b142b3a2781 100644
--- a/spec/lib/gitlab/database_spec.rb
+++ b/spec/lib/gitlab/database_spec.rb
@@ -55,6 +55,22 @@ describe Gitlab::Database, lib: true do
     end
   end
 
+  describe '.nulls_first_order' do
+    context 'when using PostgreSQL' do
+      before { expect(described_class).to receive(:postgresql?).and_return(true) }
+
+      it { expect(described_class.nulls_first_order('column', 'ASC')).to eq 'column ASC NULLS FIRST'}
+      it { expect(described_class.nulls_first_order('column', 'DESC')).to eq 'column DESC NULLS FIRST'}
+    end
+
+    context 'when using MySQL' do
+      before { expect(described_class).to receive(:postgresql?).and_return(false) }
+
+      it { expect(described_class.nulls_first_order('column', 'ASC')).to eq 'column ASC'}
+      it { expect(described_class.nulls_first_order('column', 'DESC')).to eq 'column IS NULL, column DESC'}
+    end
+  end
+
   describe '#true_value' do
     it 'returns correct value for PostgreSQL' do
       expect(described_class).to receive(:postgresql?).and_return(true)
diff --git a/spec/lib/gitlab/route_map_spec.rb b/spec/lib/gitlab/route_map_spec.rb
new file mode 100644
index 00000000000..459fa8a63a9
--- /dev/null
+++ b/spec/lib/gitlab/route_map_spec.rb
@@ -0,0 +1,90 @@
+require 'spec_helper'
+
+describe Gitlab::RouteMap, lib: true do
+  describe '#initialize' do
+    context 'when the data is not YAML' do
+      it 'raises an error' do
+        expect { described_class.new('"') }.
+          to raise_error(Gitlab::RouteMap::FormatError, /valid YAML/)
+      end
+    end
+
+    context 'when the data is not a YAML array' do
+      it 'raises an error' do
+        expect { described_class.new(YAML.dump('foo')) }.
+          to raise_error(Gitlab::RouteMap::FormatError, /an array/)
+      end
+    end
+
+    context 'when an entry is not a hash' do
+      it 'raises an error' do
+        expect { described_class.new(YAML.dump(['foo'])) }.
+          to raise_error(Gitlab::RouteMap::FormatError, /a hash/)
+      end
+    end
+
+    context 'when an entry does not have a source key' do
+      it 'raises an error' do
+        expect { described_class.new(YAML.dump([{ 'public' => 'index.html' }])) }.
+          to raise_error(Gitlab::RouteMap::FormatError, /source key/)
+      end
+    end
+
+    context 'when an entry does not have a public key' do
+      it 'raises an error' do
+        expect { described_class.new(YAML.dump([{ 'source' => '/index\.html/' }])) }.
+          to raise_error(Gitlab::RouteMap::FormatError, /public key/)
+      end
+    end
+
+    context 'when an entry source does not start and end with a slash' do
+      it 'raises an error' do
+        expect { described_class.new(YAML.dump([{ 'source' => 'index.html', 'public' => 'index.html' }])) }.
+          to raise_error(Gitlab::RouteMap::FormatError, /a slash/)
+      end
+    end
+
+    context 'when an entry source is not a valid regex' do
+      it 'raises an error' do
+        expect { described_class.new(YAML.dump([{ 'source' => '/[/', 'public' => 'index.html' }])) }.
+          to raise_error(Gitlab::RouteMap::FormatError, /regular expression/)
+      end
+    end
+
+    context 'when all is good' do
+      it 'returns a route map' do
+        route_map = described_class.new(YAML.dump([{ 'source' => '/index\.html/', 'public' => 'index.html' }]))
+        
+        expect(route_map.public_path_for_source_path('index.html')).to eq('index.html')
+      end
+    end
+  end
+
+  describe '#public_path_for_source_path' do
+    subject do
+      described_class.new(<<-'MAP'.strip_heredoc)
+        # Blogposts
+        - source: /source/posts/([0-9]{4})-([0-9]{2})-([0-9]{2})-(.+?)\..*/ # source/posts/2017-01-30-around-the-world-in-6-releases.html.md.erb
+          public: '\1/\2/\3/\4/' # 2017/01/30/around-the-world-in-6-releases/
+
+        # HTML files
+        - source: /source/(.+?\.html).*/ # source/index.html.haml
+          public: '\1' # index.html
+
+        # Other files
+        - source: /source/(.*)/ # source/images/blogimages/around-the-world-in-6-releases-cover.png
+          public: '\1' # images/blogimages/around-the-world-in-6-releases-cover.png
+      MAP
+    end
+
+    it 'returns the public path for a provided source path' do
+      expect(subject.public_path_for_source_path('source/posts/2017-01-30-around-the-world-in-6-releases.html.md.erb')).to eq('2017/01/30/around-the-world-in-6-releases/')
+
+      expect(subject.public_path_for_source_path('source/index.html.haml')).to eq('index.html')
+
+      expect(subject.public_path_for_source_path('source/images/blogimages/around-the-world-in-6-releases-cover.png')).to eq('images/blogimages/around-the-world-in-6-releases-cover.png')
+
+      expect(subject.public_path_for_source_path('.gitlab/route-map.yml')).to be_nil
+    end
+  end
+end
diff --git a/spec/models/environment_spec.rb b/spec/models/environment_spec.rb
index 8b57d8600fe..960f29f3805 100644
--- a/spec/models/environment_spec.rb
+++ b/spec/models/environment_spec.rb
@@ -7,8 +7,6 @@ describe Environment, models: true do
   it { is_expected.to belong_to(:project) }
   it { is_expected.to have_many(:deployments) }
 
-  it { is_expected.to delegate_method(:last_deployment).to(:deployments).as(:last) }
-
   it { is_expected.to delegate_method(:stop_action).to(:last_deployment) }
   it { is_expected.to delegate_method(:manual_actions).to(:last_deployment) }
 
@@ -22,6 +20,20 @@ describe Environment, models: true do
   it { is_expected.to validate_length_of(:external_url).is_at_most(255) }
   it { is_expected.to validate_uniqueness_of(:external_url).scoped_to(:project_id) }
 
+  describe '.order_by_last_deployed_at' do
+    let(:project) { create(:project) }
+    let!(:environment1) { create(:environment, project: project) }
+    let!(:environment2) { create(:environment, project: project) }
+    let!(:environment3) { create(:environment, project: project) }
+    let!(:deployment1) { create(:deployment, environment: environment1) }
+    let!(:deployment2) { create(:deployment, environment: environment2) }
+    let!(:deployment3) { create(:deployment, environment: environment1) }
+
+    it 'returns the environments in order of having been last deployed' do
+      expect(project.environments.order_by_last_deployed_at.to_a).to eq([environment3, environment2, environment1])
+    end
+  end
+
   describe '#nullify_external_url' do
     it 'replaces a blank url with nil' do
       env = build(:environment, external_url: "")
@@ -323,4 +335,33 @@ describe Environment, models: true do
       end
     end
   end
+
+  describe '#external_url_for' do
+    let(:source_path) { 'source/file.html' }
+    let(:sha) { RepoHelpers.sample_commit.id }
+
+    before do
+      environment.external_url = 'http://example.com'
+    end
+
+    context 'when the public path is not known' do
+      before do
+        allow(project).to receive(:public_path_for_source_path).with(source_path, sha).and_return(nil)
+      end
+
+      it 'returns nil' do
+        expect(environment.external_url_for(source_path, sha)).to be_nil
+      end
+    end
+
+    context 'when the public path is known' do
+      before do
+        allow(project).to receive(:public_path_for_source_path).with(source_path, sha).and_return('file.html')
+      end
+
+      it 'returns the full external URL' do
+        expect(environment.external_url_for(source_path, sha)).to eq('http://example.com/file.html')
+      end
+    end
+  end
 end
diff --git a/spec/models/merge_request_spec.rb b/spec/models/merge_request_spec.rb
index 32ed1e96749..e1e99300489 100644
--- a/spec/models/merge_request_spec.rb
+++ b/spec/models/merge_request_spec.rb
@@ -1005,10 +1005,16 @@ describe MergeRequest, models: true do
     end
   end
 
-  describe "#environments" do
+  describe "#environments_for" do
     let(:project)       { create(:project, :repository) }
+    let(:user)          { project.creator }
     let(:merge_request) { create(:merge_request, source_project: project) }
 
+    before do
+      merge_request.source_project.add_master(user)
+      merge_request.target_project.add_master(user)
+    end
+
     context 'with multiple environments' do
       let(:environments) { create_list(:environment, 3, project: project) }
 
@@ -1018,7 +1024,7 @@ describe MergeRequest, models: true do
       end
 
       it 'selects deployed environments' do
-        expect(merge_request.environments).to contain_exactly(environments.first)
+        expect(merge_request.environments_for(user)).to contain_exactly(environments.first)
       end
     end
 
@@ -1042,7 +1048,7 @@ describe MergeRequest, models: true do
       end
 
       it 'selects deployed environments' do
-        expect(merge_request.environments).to contain_exactly(source_environment)
+        expect(merge_request.environments_for(user)).to contain_exactly(source_environment)
       end
 
       context 'with environments on target project' do
@@ -1053,7 +1059,7 @@ describe MergeRequest, models: true do
         end
 
         it 'selects deployed environments' do
-          expect(merge_request.environments).to contain_exactly(source_environment, target_environment)
+          expect(merge_request.environments_for(user)).to contain_exactly(source_environment, target_environment)
         end
       end
     end
@@ -1064,7 +1070,7 @@ describe MergeRequest, models: true do
       end
 
       it 'returns an empty array' do
-        expect(merge_request.environments).to be_empty
+        expect(merge_request.environments_for(user)).to be_empty
       end
     end
   end
diff --git a/spec/models/project_spec.rb b/spec/models/project_spec.rb
index d7e6da02261..2129bcbd74d 100644
--- a/spec/models/project_spec.rb
+++ b/spec/models/project_spec.rb
@@ -1716,100 +1716,6 @@ describe Project, models: true do
     end
   end
 
-  describe '#environments_for' do
-    let(:project) { create(:project, :repository) }
-    let(:environment) { create(:environment, project: project) }
-
-    context 'tagged deployment' do
-      before do
-        create(:deployment, environment: environment, ref: '1.0', tag: true, sha: project.commit.id)
-      end
-
-      it 'returns environment when with_tags is set' do
-        expect(project.environments_for('master', commit: project.commit, with_tags: true))
-          .to contain_exactly(environment)
-      end
-
-      it 'does not return environment when no with_tags is set' do
-        expect(project.environments_for('master', commit: project.commit))
-          .to be_empty
-      end
-
-      it 'does not return environment when commit is not part of deployment' do
-        expect(project.environments_for('master', commit: project.commit('feature')))
-          .to be_empty
-      end
-    end
-
-    context 'branch deployment' do
-      before do
-        create(:deployment, environment: environment, ref: 'master', sha: project.commit.id)
-      end
-
-      it 'returns environment when ref is set' do
-        expect(project.environments_for('master', commit: project.commit))
-          .to contain_exactly(environment)
-      end
-
-      it 'does not environment when ref is different' do
-        expect(project.environments_for('feature', commit: project.commit))
-          .to be_empty
-      end
-
-      it 'does not return environment when commit is not part of deployment' do
-        expect(project.environments_for('master', commit: project.commit('feature')))
-          .to be_empty
-      end
-
-      it 'returns environment when commit constraint is not set' do
-        expect(project.environments_for('master'))
-          .to contain_exactly(environment)
-      end
-    end
-  end
-
-  describe '#environments_recently_updated_on_branch' do
-    let(:project) { create(:project, :repository) }
-    let(:environment) { create(:environment, project: project) }
-
-    context 'when last deployment to environment is the most recent one' do
-      before do
-        create(:deployment, environment: environment, ref: 'feature')
-      end
-
-      it 'finds recently updated environment' do
-        expect(project.environments_recently_updated_on_branch('feature'))
-          .to contain_exactly(environment)
-      end
-    end
-
-    context 'when last deployment to environment is not the most recent' do
-      before do
-        create(:deployment, environment: environment, ref: 'feature')
-        create(:deployment, environment: environment, ref: 'master')
-      end
-
-      it 'does not find environment' do
-        expect(project.environments_recently_updated_on_branch('feature'))
-          .to be_empty
-      end
-    end
-
-    context 'when there are two environments that deploy to the same branch' do
-      let(:second_environment) { create(:environment, project: project) }
-
-      before do
-        create(:deployment, environment: environment, ref: 'feature')
-        create(:deployment, environment: second_environment, ref: 'feature')
-      end
-
-      it 'finds both environments' do
-        expect(project.environments_recently_updated_on_branch('feature'))
-          .to contain_exactly(environment, second_environment)
-      end
-    end
-  end
-
   describe '#deployment_variables' do
     context 'when project has no deployment service' do
       let(:project) { create(:empty_project) }
@@ -1858,6 +1764,82 @@ describe Project, models: true do
     it { expect(Project.inside_path(path)).to eq([project1]) }
   end
 
+  describe '#route_map_for' do
+    let(:project) { create(:project) }
+    let(:route_map) do
+      <<-MAP.strip_heredoc
+      - source: /source/(.*)/
+        public: '\\1'
+      MAP
+    end
+
+    before do
+      project.repository.commit_file(User.last, '.gitlab/route-map.yml', route_map, message: 'Add .gitlab/route-map.yml', branch_name: 'master', update: false)
+    end
+
+    context 'when there is a .gitlab/route-map.yml at the commit' do
+      context 'when the route map is valid' do
+        it 'returns a route map' do
+          map = project.route_map_for(project.commit.sha)
+          expect(map).to be_a_kind_of(Gitlab::RouteMap)
+        end
+      end
+
+      context 'when the route map is invalid' do
+        let(:route_map) { 'INVALID' }
+
+        it 'returns nil' do
+          expect(project.route_map_for(project.commit.sha)).to be_nil
+        end
+      end
+    end
+
+    context 'when there is no .gitlab/route-map.yml at the commit' do
+      it 'returns nil' do
+        expect(project.route_map_for(project.commit.parent.sha)).to be_nil
+      end
+    end
+  end
+
+  describe '#public_path_for_source_path' do
+    let(:project) { create(:project) }
+    let(:route_map) do
+      Gitlab::RouteMap.new(<<-MAP.strip_heredoc)
+        - source: /source/(.*)/
+          public: '\\1'
+      MAP
+    end
+    let(:sha) { project.commit.id }
+
+    context 'when there is a route map' do
+      before do
+        allow(project).to receive(:route_map_for).with(sha).and_return(route_map)
+      end
+
+      context 'when the source path is mapped' do
+        it 'returns the public path' do
+          expect(project.public_path_for_source_path('source/file.html', sha)).to eq('file.html')
+        end
+      end
+
+      context 'when the source path is not mapped' do
+        it 'returns nil' do
+          expect(project.public_path_for_source_path('file.html', sha)).to be_nil
+        end
+      end
+    end
+
+    context 'when there is no route map' do
+      before do
+        allow(project).to receive(:route_map_for).with(sha).and_return(nil)
+      end
+
+      it 'returns nil' do
+        expect(project.public_path_for_source_path('source/file.html', sha)).to be_nil
+      end
+    end
+  end
+
   def enable_lfs
     allow(Gitlab.config.lfs).to receive(:enabled).and_return(true)
   end
diff --git a/spec/models/repository_spec.rb b/spec/models/repository_spec.rb
index 53b98ba05f8..9bfa6409607 100644
--- a/spec/models/repository_spec.rb
+++ b/spec/models/repository_spec.rb
@@ -1782,4 +1782,40 @@ describe Repository, models: true do
       repository.refresh_method_caches(%i(readme license))
     end
   end
+
+  describe '#gitlab_ci_yml_for' do
+    before do
+      repository.commit_file(User.last, '.gitlab-ci.yml', 'CONTENT', message: 'Add .gitlab-ci.yml', branch_name: 'master', update: false)
+    end
+
+    context 'when there is a .gitlab-ci.yml at the commit' do
+      it 'returns the content' do
+        expect(repository.gitlab_ci_yml_for(repository.commit.sha)).to eq('CONTENT')
+      end
+    end
+
+    context 'when there is no .gitlab-ci.yml at the commit' do
+      it 'returns nil' do
+        expect(repository.gitlab_ci_yml_for(repository.commit.parent.sha)).to be_nil
+      end
+    end
+  end
+
+  describe '#route_map_for' do
+    before do
+      repository.commit_file(User.last, '.gitlab/route-map.yml', 'CONTENT', message: 'Add .gitlab/route-map.yml', branch_name: 'master', update: false)
+    end
+
+    context 'when there is a .gitlab/route-map.yml at the commit' do
+      it 'returns the content' do
+        expect(repository.route_map_for(repository.commit.sha)).to eq('CONTENT')
+      end
+    end
+
+    context 'when there is no .gitlab/route-map.yml at the commit' do
+      it 'returns nil' do
+        expect(repository.route_map_for(repository.commit.parent.sha)).to be_nil
+      end
+    end
+  end
 end