Add related issues backend

4 files changed, 165 insertions, 0 deletions

diff --git a/app/services/issue_links/create_service.rb b/app/services/issue_links/create_service.rb
new file mode 100644
index 00000000000..5f938e61280
--- /dev/null
+++ b/app/services/issue_links/create_service.rb
@@ -0,0 +1,47 @@
+module IssueLinks
+  class CreateService < BaseService
+    def initialize(issue, user, params)
+      @issue, @current_user, @params = issue, user, params.dup
+    end
+
+    def execute
+      if referenced_issues.blank?
+        return error('No Issue found for given reference', 401)
+      end
+
+      create_issue_links
+      success
+    end
+
+    private
+
+    def create_issue_links
+      referenced_issues.each do |referenced_issue|
+        create_notes(referenced_issue) if relate_issues(referenced_issue)
+      end
+    end
+
+    def relate_issues(referenced_issue)
+      IssueLink.create(source: @issue, target: referenced_issue)
+    end
+
+    def create_notes(referenced_issue)
+      SystemNoteService.relate_issue(@issue, referenced_issue, current_user)
+      SystemNoteService.relate_issue(referenced_issue, @issue, current_user)
+    end
+
+    def referenced_issues
+      @referenced_issues ||= begin
+        issue_references = params[:issue_references]
+        text = issue_references.join(' ')
+
+        extractor = Gitlab::ReferenceExtractor.new(@issue.project, @current_user)
+        extractor.analyze(text)
+
+        extractor.issues.select do |issue|
+          can?(current_user, :admin_issue_link, issue)
+        end
+      end
+    end
+  end
+end
diff --git a/app/services/issue_links/destroy_service.rb b/app/services/issue_links/destroy_service.rb
new file mode 100644
index 00000000000..0b08d869c9f
--- /dev/null
+++ b/app/services/issue_links/destroy_service.rb
@@ -0,0 +1,28 @@
+module IssueLinks
+  class DestroyService < BaseService
+    def initialize(issue_link, user)
+      @issue_link = issue_link
+      @current_user = user
+      @issue = issue_link.source
+      @referenced_issue = issue_link.target
+    end
+
+    def execute
+      remove_relation
+      create_notes
+
+      success(message: 'Relation was removed')
+    end
+
+    private
+
+    def remove_relation
+      @issue_link.destroy!
+    end
+
+    def create_notes
+      SystemNoteService.unrelate_issue(@issue, @referenced_issue, current_user)
+      SystemNoteService.unrelate_issue(@referenced_issue, @issue, current_user)
+    end
+  end
+end
diff --git a/app/services/issue_links/list_service.rb b/app/services/issue_links/list_service.rb
new file mode 100644
index 00000000000..609b125c31d
--- /dev/null
+++ b/app/services/issue_links/list_service.rb
@@ -0,0 +1,58 @@
+module IssueLinks
+  class ListService
+    include Gitlab::Routing
+
+    def initialize(issue, user)
+      @issue, @current_user, @project = issue, user, issue.project
+    end
+
+    def execute
+      issues.map do |referenced_issue|
+        {
+          id: referenced_issue.id,
+          title: referenced_issue.title,
+          state: referenced_issue.state,
+          reference: referenced_issue.to_reference(@project),
+          path: namespace_project_issue_path(referenced_issue.project.namespace, referenced_issue.project, referenced_issue.iid),
+          destroy_relation_path: destroy_relation_path(referenced_issue)
+        }
+      end
+    end
+
+    private
+
+    def issues
+      related_issues = Issue
+                         .select(['issues.*', 'issue_links.id AS issue_links_id'])
+                         .joins("INNER JOIN issue_links ON
+                                 (issue_links.source_id = issues.id AND issue_links.target_id = #{@issue.id})
+                                 OR
+                                 (issue_links.target_id = issues.id AND issue_links.source_id = #{@issue.id})")
+                         .preload(project: :namespace)
+                         .reorder('issue_links_id')
+
+      Ability.issues_readable_by_user(related_issues, @current_user)
+    end
+
+    def destroy_relation_path(issue)
+      # Make sure the user can admin both the current issue AND the
+      # referenced issue projects in order to return the removal link.
+      if can_destroy_issue_link_on_current_project? && can_destroy_issue_link?(issue.project)
+        namespace_project_issue_link_path(@project.namespace,
+                                          @issue.project,
+                                          @issue.iid,
+                                          issue.issue_links_id)
+      end
+    end
+
+    def can_destroy_issue_link_on_current_project?
+      return @can_destroy_on_current_project if defined?(@can_destroy_on_current_project)
+
+      @can_destroy_on_current_project = can_destroy_issue_link?(@project)
+    end
+
+    def can_destroy_issue_link?(project)
+      Ability.allowed?(@current_user, :admin_issue_link, project)
+    end
+  end
+end
diff --git a/app/services/system_note_service.rb b/app/services/system_note_service.rb
index 01d572e5efd..ac47f42c6c1 100644
--- a/app/services/system_note_service.rb
+++ b/app/services/system_note_service.rb
@@ -552,6 +552,38 @@ module SystemNoteService
     create_note(NoteSummary.new(noteable, project, author, body, action: 'moved'))
   end
 
+  #
+  # noteable     - Noteable object
+  # noteable_ref - Referenced noteable object
+  # user         - User performing reference
+  #
+  # Example Note text:
+  #
+  #   "marked this issue as related to gitlab-ce#9001"
+  #
+  # Returns the created Note object
+  def relate_issue(noteable, noteable_ref, user)
+    body = "marked this issue as related to #{noteable_ref.to_reference(noteable.project)}"
+
+    create_note(NoteSummary.new(noteable, noteable.project, user, body, action: 'relate'))
+  end
+
+  #
+  # noteable     - Noteable object
+  # noteable_ref - Referenced noteable object
+  # user         - User performing reference
+  #
+  # Example Note text:
+  #
+  #   "removed the relation with gitlab-ce#9001"
+  #
+  # Returns the created Note object
+  def unrelate_issue(noteable, noteable_ref, user)
+    body = "removed the relation with #{noteable_ref.to_reference(noteable.project)}"
+
+    create_note(NoteSummary.new(noteable, noteable.project, user, body, action: 'unrelate'))
+  end
+
   # Called when the merge request is approved by user
   #
   # noteable - Noteable object