Merge branch 'master' into remove-old-isobjectremove-old-isobject

* master: (226 commits)
  Real time pipeline show action
  Fix `Routable.find_by_full_path` on MySQL
  add CHANGELOG.md entry for !11138
  add tooltips to user contrib graph key
  Use an absolute path for locale path in FastGettext config
  Colorize labels in issue search field
  Fix Karma failures for jQuery deferreds
  Reduce risk of deadlocks
  Fix failing spec and eslint
  Resolve discussions
  Resolve discussions
  Dry up routable lookups. Fixes #30317
  Add “project moved” flash message on redirect
  Resolve discussions
  Fix Rubocop failures
  Index redirect_routes path for LIKE
  Add index for source association and for path
  Fix or workaround spec failure
  Refactor
  Delete conflicting redirects
  ...

21 files changed, 260 insertions, 59 deletions

diff --git a/app/models/application_setting.rb b/app/models/application_setting.rb
index cf042717c95..54f01f8637e 100644
--- a/app/models/application_setting.rb
+++ b/app/models/application_setting.rb
@@ -62,6 +62,10 @@ class ApplicationSetting < ActiveRecord::Base
             presence: true,
             if: :sentry_enabled
 
+  validates :clientside_sentry_dsn,
+            presence: true,
+            if: :clientside_sentry_enabled
+
   validates :akismet_api_key,
             presence: true,
             if: :akismet_enabled
diff --git a/app/models/blob.rb b/app/models/blob.rb
index a4fae22a0c4..eaf0b713122 100644
--- a/app/models/blob.rb
+++ b/app/models/blob.rb
@@ -26,6 +26,7 @@ class Blob < SimpleDelegator
 
     BlobViewer::Image,
     BlobViewer::Sketch,
+    BlobViewer::Balsamiq,
 
     BlobViewer::Video,
 
diff --git a/app/models/blob_viewer/balsamiq.rb b/app/models/blob_viewer/balsamiq.rb
new file mode 100644
index 00000000000..f982521db99
--- /dev/null
+++ b/app/models/blob_viewer/balsamiq.rb
@@ -0,0 +1,12 @@
+module BlobViewer
+  class Balsamiq < Base
+    include Rich
+    include ClientSide
+
+    self.partial_name = 'balsamiq'
+    self.extensions = %w(bmpr)
+    self.binary = true
+    self.switcher_icon = 'file-image-o'
+    self.switcher_title = 'preview'
+  end
+end
diff --git a/app/models/ci/build.rb b/app/models/ci/build.rb
index b426c27afbb..971ab7cb0ee 100644
--- a/app/models/ci/build.rb
+++ b/app/models/ci/build.rb
@@ -111,14 +111,9 @@ module Ci
     end
 
     def play(current_user)
-      # Try to queue a current build
-      if self.enqueue
-        self.update(user: current_user)
-        self
-      else
-        # Otherwise we need to create a duplicate
-        Ci::Build.retry(self, current_user)
-      end
+      Ci::PlayBuildService
+        .new(project, current_user)
+        .execute(self)
     end
 
     def cancelable?
diff --git a/app/models/ci/group.rb b/app/models/ci/group.rb
new file mode 100644
index 00000000000..87898b086c6
--- /dev/null
+++ b/app/models/ci/group.rb
@@ -0,0 +1,40 @@
+module Ci
+  ##
+  # This domain model is a representation of a group of jobs that are related
+  # to each other, like `rspec 0 1`, `rspec 0 2`.
+  #
+  # It is not persisted in the database.
+  #
+  class Group
+    include StaticModel
+
+    attr_reader :stage, :name, :jobs
+
+    delegate :size, to: :jobs
+
+    def initialize(stage, name:, jobs:)
+      @stage = stage
+      @name = name
+      @jobs = jobs
+    end
+
+    def status
+      @status ||= commit_statuses.status
+    end
+
+    def detailed_status(current_user)
+      if jobs.one?
+        jobs.first.detailed_status(current_user)
+      else
+        Gitlab::Ci::Status::Group::Factory
+          .new(self, current_user).fabricate!
+      end
+    end
+
+    private
+
+    def commit_statuses
+      @commit_statuses ||= CommitStatus.where(id: jobs.map(&:id))
+    end
+  end
+end
diff --git a/app/models/ci/stage.rb b/app/models/ci/stage.rb
index e7d6b17d445..9bda3186c30 100644
--- a/app/models/ci/stage.rb
+++ b/app/models/ci/stage.rb
@@ -15,6 +15,14 @@ module Ci
       @warnings = warnings
     end
 
+    def groups
+      @groups ||= statuses.ordered.latest
+        .sort_by(&:sortable_name).group_by(&:group_name)
+        .map do |group_name, grouped_statuses|
+          Ci::Group.new(self, name: group_name, jobs: grouped_statuses)
+        end
+    end
+
     def to_param
       name
     end
diff --git a/app/models/concerns/issuable.rb b/app/models/concerns/issuable.rb
index 26dbf4d9570..075ec575f9d 100644
--- a/app/models/concerns/issuable.rb
+++ b/app/models/concerns/issuable.rb
@@ -26,8 +26,8 @@ module Issuable
     cache_markdown_field :description, issuable_state_filter_enabled: true
 
     belongs_to :author, class_name: "User"
-    belongs_to :assignee, class_name: "User"
     belongs_to :updated_by, class_name: "User"
+    belongs_to :last_edited_by, class_name: 'User'
     belongs_to :milestone
     has_many :notes, as: :noteable, inverse_of: :noteable, dependent: :destroy do
       def authors_loaded?
@@ -65,11 +65,8 @@ module Issuable
     validates :title, presence: true, length: { maximum: 255 }
 
     scope :authored, ->(user) { where(author_id: user) }
-    scope :assigned_to, ->(u) { where(assignee_id: u.id)}
     scope :recent, -> { reorder(id: :desc) }
     scope :order_position_asc, -> { reorder(position: :asc) }
-    scope :assigned, -> { where("assignee_id IS NOT NULL") }
-    scope :unassigned, -> { where("assignee_id IS NULL") }
     scope :of_projects, ->(ids) { where(project_id: ids) }
     scope :of_milestones, ->(ids) { where(milestone_id: ids) }
     scope :with_milestone, ->(title) { left_joins_milestones.where(milestones: { title: title }) }
@@ -92,23 +89,14 @@ module Issuable
     attr_mentionable :description
 
     participant :author
-    participant :assignee
     participant :notes_with_associations
 
     strip_attributes :title
 
     acts_as_paranoid
 
-    after_save :update_assignee_cache_counts, if: :assignee_id_changed?
     after_save :record_metrics, unless: :imported?
 
-    def update_assignee_cache_counts
-      # make sure we flush the cache for both the old *and* new assignees(if they exist)
-      previous_assignee = User.find_by_id(assignee_id_was) if assignee_id_was
-      previous_assignee&.update_cache_counts
-      assignee&.update_cache_counts
-    end
-
     # We want to use optimistic lock for cases when only title or description are involved
     # http://api.rubyonrails.org/classes/ActiveRecord/Locking/Optimistic.html
     def locking_enabled?
@@ -237,10 +225,6 @@ module Issuable
     today? && created_at == updated_at
   end
 
-  def is_being_reassigned?
-    assignee_id_changed?
-  end
-
   def open?
     opened? || reopened?
   end
@@ -269,7 +253,11 @@ module Issuable
       # DEPRECATED
       repository: project.hook_attrs.slice(:name, :url, :description, :homepage)
     }
-    hook_data[:assignee] = assignee.hook_attrs if assignee
+    if self.is_a?(Issue)
+      hook_data[:assignees] = assignees.map(&:hook_attrs) if assignees.any?
+    else
+      hook_data[:assignee] = assignee.hook_attrs if assignee
+    end
 
     hook_data
   end
@@ -331,11 +319,6 @@ module Issuable
     false
   end
 
-  def assignee_or_author?(user)
-    # We're comparing IDs here so we don't need to load any associations.
-    author_id == user.id || assignee_id == user.id
-  end
-
   def record_metrics
     metrics = self.metrics || create_metrics
     metrics.record!
diff --git a/app/models/concerns/milestoneish.rb b/app/models/concerns/milestoneish.rb
index f449229864d..a3472af5c55 100644
--- a/app/models/concerns/milestoneish.rb
+++ b/app/models/concerns/milestoneish.rb
@@ -40,7 +40,7 @@ module Milestoneish
   def issues_visible_to_user(user)
     memoize_per_user(user, :issues_visible_to_user) do
       IssuesFinder.new(user, issues_finder_params)
-        .execute.where(milestone_id: milestoneish_ids)
+        .execute.includes(:assignees).where(milestone_id: milestoneish_ids)
     end
   end
 
diff --git a/app/models/concerns/routable.rb b/app/models/concerns/routable.rb
index b28e05d0c28..c4463abdfe6 100644
--- a/app/models/concerns/routable.rb
+++ b/app/models/concerns/routable.rb
@@ -5,6 +5,7 @@ module Routable
 
   included do
     has_one :route, as: :source, autosave: true, dependent: :destroy
+    has_many :redirect_routes, as: :source, autosave: true, dependent: :destroy
 
     validates_associated :route
     validates :route, presence: true
@@ -26,16 +27,31 @@ module Routable
     #     Klass.find_by_full_path('gitlab-org/gitlab-ce')
     #
     # Returns a single object, or nil.
-    def find_by_full_path(path)
+    def find_by_full_path(path, follow_redirects: false)
       # On MySQL we want to ensure the ORDER BY uses a case-sensitive match so
       # any literal matches come first, for this we have to use "BINARY".
       # Without this there's still no guarantee in what order MySQL will return
       # rows.
+      #
+      # Why do we do this?
+      #
+      # Even though we have Rails validation on Route for unique paths
+      # (case-insensitive), there are old projects in our DB (and possibly
+      # clients' DBs) that have the same path with different cases.
+      # See https://gitlab.com/gitlab-org/gitlab-ce/issues/18603. Also note that
+      # our unique index is case-sensitive in Postgres.
       binary = Gitlab::Database.mysql? ? 'BINARY' : ''
-
       order_sql = "(CASE WHEN #{binary} routes.path = #{connection.quote(path)} THEN 0 ELSE 1 END)"
-
-      where_full_path_in([path]).reorder(order_sql).take
+      found = where_full_path_in([path]).reorder(order_sql).take
+      return found if found
+
+      if follow_redirects
+        if Gitlab::Database.postgresql?
+          joins(:redirect_routes).find_by("LOWER(redirect_routes.path) = LOWER(?)", path)
+        else
+          joins(:redirect_routes).find_by(redirect_routes: { path: path })
+        end
+      end
     end
 
     # Builds a relation to find multiple objects by their full paths.
diff --git a/app/models/deployment.rb b/app/models/deployment.rb
index afad001d50f..37adfb4de73 100644
--- a/app/models/deployment.rb
+++ b/app/models/deployment.rb
@@ -85,8 +85,8 @@ class Deployment < ActiveRecord::Base
   end
 
   def stop_action
-    return nil unless on_stop.present?
-    return nil unless manual_actions
+    return unless on_stop.present?
+    return unless manual_actions
 
     @stop_action ||= manual_actions.find_by(name: on_stop)
   end
diff --git a/app/models/global_milestone.rb b/app/models/global_milestone.rb
index 0afbca2cb32..538615130a7 100644
--- a/app/models/global_milestone.rb
+++ b/app/models/global_milestone.rb
@@ -36,7 +36,7 @@ class GlobalMilestone
     closed = count_by_state(milestones_by_state_and_title, 'closed')
     all = milestones_by_state_and_title.map { |(_, title), _| title }.uniq.count
 
-    { 
+    {
       opened: opened,
       closed: closed,
       all: all
@@ -86,7 +86,7 @@ class GlobalMilestone
   end
 
   def issues
-    @issues ||= Issue.of_milestones(milestoneish_ids).includes(:project, :assignee, :labels)
+    @issues ||= Issue.of_milestones(milestoneish_ids).includes(:project, :assignees, :labels)
   end
 
   def merge_requests
@@ -94,7 +94,7 @@ class GlobalMilestone
   end
 
   def participants
-    @participants ||= milestones.includes(:participants).map(&:participants).flatten.compact.uniq
+    @participants ||= milestones.map(&:participants).flatten.uniq
   end
 
   def labels
diff --git a/app/models/issue.rb b/app/models/issue.rb
index 78bde6820da..27e3ed9bc7f 100644
--- a/app/models/issue.rb
+++ b/app/models/issue.rb
@@ -24,10 +24,17 @@ class Issue < ActiveRecord::Base
 
   has_many :merge_requests_closing_issues, class_name: 'MergeRequestsClosingIssues', dependent: :delete_all
 
+  has_many :issue_assignees
+  has_many :assignees, class_name: "User", through: :issue_assignees
+
   validates :project, presence: true
 
   scope :in_projects, ->(project_ids) { where(project_id: project_ids) }
 
+  scope :assigned, -> { where('EXISTS (SELECT TRUE FROM issue_assignees WHERE issue_id = issues.id)') }
+  scope :unassigned, -> { where('NOT EXISTS (SELECT TRUE FROM issue_assignees WHERE issue_id = issues.id)') }
+  scope :assigned_to, ->(u) { where('EXISTS (SELECT TRUE FROM issue_assignees WHERE user_id = ? AND issue_id = issues.id)', u.id)}
+
   scope :without_due_date, -> { where(due_date: nil) }
   scope :due_before, ->(date) { where('issues.due_date < ?', date) }
   scope :due_between, ->(from_date, to_date) { where('issues.due_date >= ?', from_date).where('issues.due_date <= ?', to_date) }
@@ -37,13 +44,15 @@ class Issue < ActiveRecord::Base
 
   scope :created_after, -> (datetime) { where("created_at >= ?", datetime) }
 
-  scope :include_associations, -> { includes(:assignee, :labels, project: :namespace) }
+  scope :include_associations, -> { includes(:labels, project: :namespace) }
 
   after_save :expire_etag_cache
 
   attr_spammable :title, spam_title: true
   attr_spammable :description, spam_description: true
 
+  participant :assignees
+
   state_machine :state, initial: :opened do
     event :close do
       transition [:reopened, :opened] => :closed
@@ -63,10 +72,14 @@ class Issue < ActiveRecord::Base
   end
 
   def hook_attrs
+    assignee_ids = self.assignee_ids
+
     attrs = {
       total_time_spent: total_time_spent,
       human_total_time_spent: human_total_time_spent,
-      human_time_estimate: human_time_estimate
+      human_time_estimate: human_time_estimate,
+      assignee_ids: assignee_ids,
+      assignee_id: assignee_ids.first # This key is deprecated
     }
 
     attributes.merge!(attrs)
@@ -114,6 +127,22 @@ class Issue < ActiveRecord::Base
               "id DESC")
   end
 
+  # Returns a Hash of attributes to be used for Twitter card metadata
+  def card_attributes
+    {
+      'Author'   => author.try(:name),
+      'Assignee' => assignee_list
+    }
+  end
+
+  def assignee_or_author?(user)
+    author_id == user.id || assignees.exists?(user.id)
+  end
+
+  def assignee_list
+    assignees.map(&:name).to_sentence
+  end
+
   # `from` argument can be a Namespace or Project.
   def to_reference(from = nil, full: false)
     reference = "#{self.class.reference_prefix}#{iid}"
@@ -248,7 +277,7 @@ class Issue < ActiveRecord::Base
       true
     elsif confidential?
       author == user ||
-        assignee == user ||
+        assignees.include?(user) ||
         project.team.member?(user, Gitlab::Access::REPORTER)
     else
       project.public? ||
diff --git a/app/models/issue_assignee.rb b/app/models/issue_assignee.rb
new file mode 100644
index 00000000000..0663d3aaef8
--- /dev/null
+++ b/app/models/issue_assignee.rb
@@ -0,0 +1,13 @@
+class IssueAssignee < ActiveRecord::Base
+  extend Gitlab::CurrentSettings
+
+  belongs_to :issue
+  belongs_to :assignee, class_name: "User", foreign_key: :user_id
+
+  after_create :update_assignee_cache_counts
+  after_destroy :update_assignee_cache_counts
+
+  def update_assignee_cache_counts
+    assignee&.update_cache_counts
+  end
+end
diff --git a/app/models/merge_request.rb b/app/models/merge_request.rb
index 12c5481cd6d..35231bab12e 100644
--- a/app/models/merge_request.rb
+++ b/app/models/merge_request.rb
@@ -17,6 +17,8 @@ class MergeRequest < ActiveRecord::Base
 
   has_many :merge_requests_closing_issues, class_name: 'MergeRequestsClosingIssues', dependent: :delete_all
 
+  belongs_to :assignee, class_name: "User"
+
   serialize :merge_params, Hash
 
   after_create :ensure_merge_request_diff, unless: :importing?
@@ -114,8 +116,14 @@ class MergeRequest < ActiveRecord::Base
 
   scope :join_project, -> { joins(:target_project) }
   scope :references_project, -> { references(:target_project) }
+  scope :assigned, -> { where("assignee_id IS NOT NULL") }
+  scope :unassigned, -> { where("assignee_id IS NULL") }
+  scope :assigned_to, ->(u) { where(assignee_id: u.id)}
+
+  participant :assignee
 
   after_save :keep_around_commit
+  after_save :update_assignee_cache_counts, if: :assignee_id_changed?
 
   def self.reference_prefix
     '!'
@@ -177,6 +185,30 @@ class MergeRequest < ActiveRecord::Base
     work_in_progress?(title) ? title : "WIP: #{title}"
   end
 
+  def update_assignee_cache_counts
+    # make sure we flush the cache for both the old *and* new assignees(if they exist)
+    previous_assignee = User.find_by_id(assignee_id_was) if assignee_id_was
+    previous_assignee&.update_cache_counts
+    assignee&.update_cache_counts
+  end
+
+  # Returns a Hash of attributes to be used for Twitter card metadata
+  def card_attributes
+    {
+      'Author'   => author.try(:name),
+      'Assignee' => assignee.try(:name)
+    }
+  end
+
+  # This method is needed for compatibility with issues to not mess view and other code
+  def assignees
+    Array(assignee)
+  end
+
+  def assignee_or_author?(user)
+    author_id == user.id || assignee_id == user.id
+  end
+
   # `from` argument can be a Namespace or Project.
   def to_reference(from = nil, full: false)
     reference = "#{self.class.reference_prefix}#{iid}"
diff --git a/app/models/milestone.rb b/app/models/milestone.rb
index 652b1551928..c06bfe0ccdd 100644
--- a/app/models/milestone.rb
+++ b/app/models/milestone.rb
@@ -21,7 +21,6 @@ class Milestone < ActiveRecord::Base
   has_many :issues
   has_many :labels, -> { distinct.reorder('labels.title') },  through: :issues
   has_many :merge_requests
-  has_many :participants, -> { distinct.reorder('users.name') }, through: :issues, source: :assignee
   has_many :events, as: :target, dependent: :destroy
 
   scope :active, -> { with_state(:active) }
@@ -107,6 +106,10 @@ class Milestone < ActiveRecord::Base
     end
   end
 
+  def participants
+    User.joins(assigned_issues: :milestone).where("milestones.id = ?", id)
+  end
+
   def self.sort(method)
     case method.to_s
     when 'due_date_asc'
diff --git a/app/models/note.rb b/app/models/note.rb
index b06985b4a6f..46d0a4f159f 100644
--- a/app/models/note.rb
+++ b/app/models/note.rb
@@ -18,6 +18,11 @@ class Note < ActiveRecord::Base
 
   cache_markdown_field :note, pipeline: :note, issuable_state_filter_enabled: true
 
+  # Aliases to make application_helper#edited_time_ago_with_tooltip helper work properly with notes.
+  # See https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/10392/diffs#note_28719102
+  alias_attribute :last_edited_at, :updated_at
+  alias_attribute :last_edited_by, :updated_by
+
   # Attribute containing rendered and redacted Markdown as generated by
   # Banzai::ObjectRenderer.
   attr_accessor :redacted_note_html
@@ -38,6 +43,7 @@ class Note < ActiveRecord::Base
   belongs_to :noteable, polymorphic: true, touch: true
   belongs_to :author, class_name: "User"
   belongs_to :updated_by, class_name: "User"
+  belongs_to :last_edited_by, class_name: 'User'
 
   has_many :todos, dependent: :destroy
   has_many :events, as: :target, dependent: :destroy
diff --git a/app/models/redirect_route.rb b/app/models/redirect_route.rb
new file mode 100644
index 00000000000..99812bcde53
--- /dev/null
+++ b/app/models/redirect_route.rb
@@ -0,0 +1,12 @@
+class RedirectRoute < ActiveRecord::Base
+  belongs_to :source, polymorphic: true
+
+  validates :source, presence: true
+
+  validates :path,
+    length: { within: 1..255 },
+    presence: true,
+    uniqueness: { case_sensitive: false }
+
+  scope :matching_path_and_descendants, -> (path) { where('redirect_routes.path = ? OR redirect_routes.path LIKE ?', path, "#{sanitize_sql_like(path)}/%") }
+end
diff --git a/app/models/route.rb b/app/models/route.rb
index 4b3efab5c3c..12a7fa3d01b 100644
--- a/app/models/route.rb
+++ b/app/models/route.rb
@@ -8,29 +8,58 @@ class Route < ActiveRecord::Base
     presence: true,
     uniqueness: { case_sensitive: false }
 
+  after_create :delete_conflicting_redirects
+  after_update :delete_conflicting_redirects, if: :path_changed?
+  after_update :create_redirect_for_old_path
   after_update :rename_descendants
 
   scope :inside_path, -> (path) { where('routes.path LIKE ?', "#{sanitize_sql_like(path)}/%") }
 
   def rename_descendants
-    if path_changed? || name_changed?
-      descendants = self.class.inside_path(path_was)
+    return unless path_changed? || name_changed?
 
-      descendants.each do |route|
-        attributes = {}
+    descendant_routes = self.class.inside_path(path_was)
 
-        if path_changed? && route.path.present?
-          attributes[:path] = route.path.sub(path_was, path)
-        end
+    descendant_routes.each do |route|
+      attributes = {}
 
-        if name_changed? && name_was.present? && route.name.present?
-          attributes[:name] = route.name.sub(name_was, name)
-        end
+      if path_changed? && route.path.present?
+        attributes[:path] = route.path.sub(path_was, path)
+      end
 
-        # Note that update_columns skips validation and callbacks.
-        # We need this to avoid recursive call of rename_descendants method
-        route.update_columns(attributes) unless attributes.empty?
+      if name_changed? && name_was.present? && route.name.present?
+        attributes[:name] = route.name.sub(name_was, name)
+      end
+
+      if attributes.present?
+        old_path = route.path
+
+        # Callbacks must be run manually
+        route.update_columns(attributes)
+
+        # We are not calling route.delete_conflicting_redirects here, in hopes
+        # of avoiding deadlocks. The parent (self, in this method) already
+        # called it, which deletes conflicts for all descendants.
+        route.create_redirect(old_path) if attributes[:path]
       end
     end
   end
+
+  def delete_conflicting_redirects
+    conflicting_redirects.delete_all
+  end
+
+  def conflicting_redirects
+    RedirectRoute.matching_path_and_descendants(path)
+  end
+
+  def create_redirect(path)
+    RedirectRoute.create(source: source, path: path)
+  end
+
+  private
+
+  def create_redirect_for_old_path
+    create_redirect(path_was) if path_changed?
+  end
 end
diff --git a/app/models/snippet.rb b/app/models/snippet.rb
index d8860718cb5..abfbefdf9a0 100644
--- a/app/models/snippet.rb
+++ b/app/models/snippet.rb
@@ -12,6 +12,11 @@ class Snippet < ActiveRecord::Base
   cache_markdown_field :title, pipeline: :single_line
   cache_markdown_field :content
 
+  # Aliases to make application_helper#edited_time_ago_with_tooltip helper work properly with snippets.
+  # See https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/10392/diffs#note_28719102
+  alias_attribute :last_edited_at, :updated_at
+  alias_attribute :last_edited_by, :updated_by
+
   # If file_name changes, it invalidates content
   alias_method :default_content_html_invalidator, :content_html_invalidated?
   def content_html_invalidated?
diff --git a/app/models/system_note_metadata.rb b/app/models/system_note_metadata.rb
index 1e6fc837a75..b44f4fe000c 100644
--- a/app/models/system_note_metadata.rb
+++ b/app/models/system_note_metadata.rb
@@ -1,6 +1,6 @@
 class SystemNoteMetadata < ActiveRecord::Base
   ICON_TYPES = %w[
-    commit merge confidential visible label assignee cross_reference
+    commit description merge confidential visible label assignee cross_reference
     title time_tracking branch milestone discussion task moved opened closed merged
   ].freeze
 
diff --git a/app/models/user.rb b/app/models/user.rb
index 43c5fdc038d..accaa91b805 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -100,6 +100,10 @@ class User < ActiveRecord::Base
   has_many :award_emoji,              dependent: :destroy
   has_many :triggers,                 dependent: :destroy, class_name: 'Ci::Trigger', foreign_key: :owner_id
 
+  has_many :issue_assignees
+  has_many :assigned_issues, class_name: "Issue", through: :issue_assignees, source: :issue
+  has_many :assigned_merge_requests,  dependent: :nullify, foreign_key: :assignee_id, class_name: "MergeRequest"
+
   # Issues that a user owns are expected to be moved to the "ghost" user before
   # the user is destroyed. If the user owns any issues during deletion, this
   # should be treated as an exceptional condition.
@@ -333,6 +337,11 @@ class User < ActiveRecord::Base
       find_by(id: Key.unscoped.select(:user_id).where(id: key_id))
     end
 
+    def find_by_full_path(path, follow_redirects: false)
+      namespace = Namespace.find_by_full_path(path, follow_redirects: follow_redirects)
+      namespace&.owner
+    end
+
     def reference_prefix
       '@'
     end
@@ -355,6 +364,10 @@ class User < ActiveRecord::Base
     end
   end
 
+  def full_path
+    username
+  end
+
   def self.internal_attributes
     [:ghost]
   end