Merge branch 'master' into 22539-display-folders

* master: (26 commits)
  Remove extra subscribable_type filter on migration
  Add feature spec for labels subscription
  Avoid code duplication for label subscription status on label partial
  Rename LabelSubscription javascript to ProjectLabelSubscription
  Fix label subscription menu on small screens resolution
  Allow users to subscribe to a group label at group or project level
  Use button instead of an icon to subscribe/unsubscribe to labels
  Add CHANGELOG entry
  Add toggle_subscription action to Groups::LabelsController
  Allow subscriptions to be created without a project
  Use subqueries instead of joins to migrate subscriptions
  Add helper method to toggle label subscription on labels controller spec
  Remove default value for `project` argument on subscribable concern
  Use @project as default on ToggleSubscriptionAction concern
  Allow users to subscribe to group labels at project-level
  Pass project to Entities::Label to check if user is subscribed
  Fix specs to pass a project when creating subscriptions
  Refactoring label subscription toggle button text to accept a project
  Refactoring label subscription status to accept a project
  Refactoring notification service to find subscriptions per project
  ...

17 files changed, 261 insertions, 75 deletions

diff --git a/app/assets/javascripts/group_label_subscription.js.es6 b/app/assets/javascripts/group_label_subscription.js.es6
new file mode 100644
index 00000000000..eea6cd40859
--- /dev/null
+++ b/app/assets/javascripts/group_label_subscription.js.es6
@@ -0,0 +1,53 @@
+/* eslint-disable */
+(function(global) {
+  class GroupLabelSubscription {
+    constructor(container) {
+      const $container = $(container);
+      this.$dropdown = $container.find('.dropdown');
+      this.$subscribeButtons = $container.find('.js-subscribe-button');
+      this.$unsubscribeButtons = $container.find('.js-unsubscribe-button');
+
+      this.$subscribeButtons.on('click', this.subscribe.bind(this));
+      this.$unsubscribeButtons.on('click', this.unsubscribe.bind(this));
+    }
+
+    unsubscribe(event) {
+      event.preventDefault();
+
+      const url = this.$unsubscribeButtons.attr('data-url');
+
+      $.ajax({
+        type: 'POST',
+        url: url
+      }).done(() => {
+        this.toggleSubscriptionButtons();
+        this.$unsubscribeButtons.removeAttr('data-url');
+      });
+    }
+
+    subscribe(event) {
+      event.preventDefault();
+
+      const $btn = $(event.currentTarget);
+      const url = $btn.attr('data-url');
+
+      this.$unsubscribeButtons.attr('data-url', url);
+
+      $.ajax({
+        type: 'POST',
+        url: url
+      }).done(() => {
+        this.toggleSubscriptionButtons();
+      });
+    }
+
+    toggleSubscriptionButtons() {
+      this.$dropdown.toggleClass('hidden');
+      this.$subscribeButtons.toggleClass('hidden');
+      this.$unsubscribeButtons.toggleClass('hidden');
+    }
+  }
+
+  global.GroupLabelSubscription = GroupLabelSubscription;
+
+})(window.gl || (window.gl = {}));
diff --git a/app/assets/javascripts/project_label_subscription.js.es6 b/app/assets/javascripts/project_label_subscription.js.es6
new file mode 100644
index 00000000000..03a115cb35b
--- /dev/null
+++ b/app/assets/javascripts/project_label_subscription.js.es6
@@ -0,0 +1,53 @@
+/* eslint-disable */
+(function(global) {
+  class ProjectLabelSubscription {
+    constructor(container) {
+      this.$container = $(container);
+      this.$buttons = this.$container.find('.js-subscribe-button');
+
+      this.$buttons.on('click', this.toggleSubscription.bind(this));
+    }
+
+    toggleSubscription(event) {
+      event.preventDefault();
+
+      const $btn = $(event.currentTarget);
+      const $span = $btn.find('span');
+      const url = $btn.attr('data-url');
+      const oldStatus = $btn.attr('data-status');
+
+      $btn.addClass('disabled');
+      $span.toggleClass('hidden');
+
+      $.ajax({
+        type: 'POST',
+        url: url
+      }).done(() => {
+        let newStatus, newAction;
+
+        if (oldStatus === 'unsubscribed') {
+          [newStatus, newAction] = ['subscribed', 'Unsubscribe'];
+        } else {
+          [newStatus, newAction] = ['unsubscribed', 'Subscribe'];
+        }
+
+        $span.toggleClass('hidden');
+        $btn.removeClass('disabled');
+
+        this.$buttons.attr('data-status', newStatus);
+        this.$buttons.find('> span').text(newAction);
+
+        for (let button of this.$buttons) {
+          let $button = $(button);
+
+          if ($button.attr('data-original-title')) {
+            $button.tooltip('hide').attr('data-original-title', newAction).tooltip('fixTitle');
+          }
+        }
+      });
+    }
+  }
+
+  global.ProjectLabelSubscription = ProjectLabelSubscription;
+
+})(window.gl || (window.gl = {}));
diff --git a/app/assets/stylesheets/pages/labels.scss b/app/assets/stylesheets/pages/labels.scss
index 397f89f501a..e39ce19f846 100644
--- a/app/assets/stylesheets/pages/labels.scss
+++ b/app/assets/stylesheets/pages/labels.scss
@@ -90,7 +90,7 @@
 
     @media (min-width: $screen-sm-min) {
       display: inline-block;
-      width: 40%;
+      width: 30%;
       margin-left: 10px;
       margin-bottom: 0;
       vertical-align: middle;
@@ -222,6 +222,14 @@
   width: 100%;
 }
 
+.label-subscription {
+  vertical-align: middle;
+
+  .dropdown-group-label a {
+    cursor: pointer;
+  }
+}
+
 .label-subscribe-button {
   .label-subscribe-button-icon {
     &[disabled] {
diff --git a/app/controllers/concerns/toggle_subscription_action.rb b/app/controllers/concerns/toggle_subscription_action.rb
index 9e3b9be2ff4..92cb534343e 100644
--- a/app/controllers/concerns/toggle_subscription_action.rb
+++ b/app/controllers/concerns/toggle_subscription_action.rb
@@ -4,13 +4,17 @@ module ToggleSubscriptionAction
   def toggle_subscription
     return unless current_user
 
-    subscribable_resource.toggle_subscription(current_user)
+    subscribable_resource.toggle_subscription(current_user, subscribable_project)
 
     head :ok
   end
 
   private
 
+  def subscribable_project
+    @project || raise(NotImplementedError)
+  end
+
   def subscribable_resource
     raise NotImplementedError
   end
diff --git a/app/controllers/groups/labels_controller.rb b/app/controllers/groups/labels_controller.rb
index 29528b2cfaa..587898a8634 100644
--- a/app/controllers/groups/labels_controller.rb
+++ b/app/controllers/groups/labels_controller.rb
@@ -1,4 +1,6 @@
 class Groups::LabelsController < Groups::ApplicationController
+  include ToggleSubscriptionAction
+
   before_action :label, only: [:edit, :update, :destroy]
   before_action :authorize_admin_labels!, only: [:new, :create, :edit, :update, :destroy]
   before_action :save_previous_label_path, only: [:edit]
@@ -69,6 +71,11 @@ class Groups::LabelsController < Groups::ApplicationController
   def label
     @label ||= @group.labels.find(params[:id])
   end
+  alias_method :subscribable_resource, :label
+
+  def subscribable_project
+    nil
+  end
 
   def label_params
     params.require(:label).permit(:title, :description, :color)
diff --git a/app/controllers/projects/labels_controller.rb b/app/controllers/projects/labels_controller.rb
index 42fd09e9b7e..824ed7be73e 100644
--- a/app/controllers/projects/labels_controller.rb
+++ b/app/controllers/projects/labels_controller.rb
@@ -3,7 +3,7 @@ class Projects::LabelsController < Projects::ApplicationController
 
   before_action :module_enabled
   before_action :label, only: [:edit, :update, :destroy]
-  before_action :find_labels, only: [:index, :set_priorities, :remove_priority]
+  before_action :find_labels, only: [:index, :set_priorities, :remove_priority, :toggle_subscription]
   before_action :authorize_read_label!
   before_action :authorize_admin_labels!, only: [:new, :create, :edit, :update,
                                                  :generate, :destroy, :remove_priority,
@@ -123,7 +123,10 @@ class Projects::LabelsController < Projects::ApplicationController
   def label
     @label ||= @project.labels.find(params[:id])
   end
-  alias_method :subscribable_resource, :label
+
+  def subscribable_resource
+    @available_labels.find(params[:id])
+  end
 
   def find_labels
     @available_labels ||= LabelsFinder.new(current_user, project_id: @project.id).execute
diff --git a/app/controllers/sent_notifications_controller.rb b/app/controllers/sent_notifications_controller.rb
index 3085ff33aba..04c36b3ebfe 100644
--- a/app/controllers/sent_notifications_controller.rb
+++ b/app/controllers/sent_notifications_controller.rb
@@ -12,7 +12,7 @@ class SentNotificationsController < ApplicationController
 
   def unsubscribe_and_redirect
     noteable = @sent_notification.noteable
-    noteable.unsubscribe(@sent_notification.recipient)
+    noteable.unsubscribe(@sent_notification.recipient, @sent_notification.project)
 
     flash[:notice] = "You have been unsubscribed from this thread."
 
diff --git a/app/helpers/labels_helper.rb b/app/helpers/labels_helper.rb
index 221a84b042f..4f180456b16 100644
--- a/app/helpers/labels_helper.rb
+++ b/app/helpers/labels_helper.rb
@@ -68,14 +68,6 @@ module LabelsHelper
     end
   end
 
-  def toggle_subscription_data(label)
-    return unless label.is_a?(ProjectLabel)
-
-    {
-      url: toggle_subscription_namespace_project_label_path(label.project.namespace, label.project, label)
-    }
-  end
-
   def render_colored_label(label, label_suffix = '', tooltip: true)
     label_color = label.color || Label::DEFAULT_COLOR
     text_color = text_color_for_bg(label_color)
@@ -148,20 +140,24 @@ module LabelsHelper
     end
   end
 
-  def label_subscription_status(label)
-    case label
-    when GroupLabel then 'Subscribing to group labels is currently not supported.'
-    when ProjectLabel then label.subscribed?(current_user) ? 'subscribed' : 'unsubscribed'
-    end
+  def label_subscription_status(label, project)
+    return 'project-level' if label.subscribed?(current_user, project)
+    return 'group-level' if label.subscribed?(current_user)
+
+    'unsubscribed'
   end
 
-  def label_subscription_toggle_button_text(label)
-    case label
-    when GroupLabel then 'Subscribing to group labels is currently not supported.'
-    when ProjectLabel then label.subscribed?(current_user) ? 'Unsubscribe' : 'Subscribe'
+  def group_label_unsubscribe_path(label, project)
+    case label_subscription_status(label, project)
+    when 'project-level' then toggle_subscription_namespace_project_label_path(@project.namespace, @project, label)
+    when 'group-level' then toggle_subscription_group_label_path(label.group, label)
     end
   end
 
+  def label_subscription_toggle_button_text(label, project)
+    label.subscribed?(current_user, project) ? 'Unsubscribe' : 'Subscribe'
+  end
+
   def label_deletion_confirm_text(label)
     case label
     when GroupLabel then 'Remove this label? This will affect all projects within the group. Are you sure?'
diff --git a/app/models/concerns/issuable.rb b/app/models/concerns/issuable.rb
index 664bb594aa9..ec9e7e5ae2b 100644
--- a/app/models/concerns/issuable.rb
+++ b/app/models/concerns/issuable.rb
@@ -215,7 +215,7 @@ module Issuable
     end
   end
 
-  def subscribed_without_subscriptions?(user)
+  def subscribed_without_subscriptions?(user, project)
     participants(user).include?(user)
   end
 
diff --git a/app/models/concerns/subscribable.rb b/app/models/concerns/subscribable.rb
index 083257f1005..83daa9b1a64 100644
--- a/app/models/concerns/subscribable.rb
+++ b/app/models/concerns/subscribable.rb
@@ -12,39 +12,71 @@ module Subscribable
     has_many :subscriptions, dependent: :destroy, as: :subscribable
   end
 
-  def subscribed?(user)
-    if subscription = subscriptions.find_by_user_id(user.id)
+  def subscribed?(user, project = nil)
+    if subscription = subscriptions.find_by(user: user, project: project)
       subscription.subscribed
     else
-      subscribed_without_subscriptions?(user)
+      subscribed_without_subscriptions?(user, project)
     end
   end
 
   # Override this method to define custom logic to consider a subscribable as
   # subscribed without an explicit subscription record.
-  def subscribed_without_subscriptions?(user)
+  def subscribed_without_subscriptions?(user, project)
     false
   end
 
-  def subscribers
-    subscriptions.where(subscribed: true).map(&:user)
+  def subscribers(project)
+    subscriptions_available(project).
+      where(subscribed: true).
+      map(&:user)
   end
 
-  def toggle_subscription(user)
-    subscriptions.
-      find_or_initialize_by(user_id: user.id).
-      update(subscribed: !subscribed?(user))
+  def toggle_subscription(user, project = nil)
+    unsubscribe_from_other_levels(user, project)
+
+    find_or_initialize_subscription(user, project).
+      update(subscribed: !subscribed?(user, project))
+  end
+
+  def subscribe(user, project = nil)
+    unsubscribe_from_other_levels(user, project)
+
+    find_or_initialize_subscription(user, project)
+      .update(subscribed: true)
+  end
+
+  def unsubscribe(user, project = nil)
+    unsubscribe_from_other_levels(user, project)
+
+    find_or_initialize_subscription(user, project)
+      .update(subscribed: false)
   end
 
-  def subscribe(user)
+  private
+
+  def unsubscribe_from_other_levels(user, project)
+    other_subscriptions = subscriptions.where(user: user)
+
+    other_subscriptions =
+      if project.blank?
+        other_subscriptions.where.not(project: nil)
+      else
+        other_subscriptions.where(project: nil)
+      end
+
+    other_subscriptions.update_all(subscribed: false)
+  end
+
+  def find_or_initialize_subscription(user, project)
     subscriptions.
-      find_or_initialize_by(user_id: user.id).
-      update(subscribed: true)
+      find_or_initialize_by(user_id: user.id, project_id: project.try(:id))
   end
 
-  def unsubscribe(user)
+  def subscriptions_available(project)
+    t = Subscription.arel_table
+
     subscriptions.
-      find_or_initialize_by(user_id: user.id).
-      update(subscribed: false)
+      where(t[:project_id].eq(nil).or(t[:project_id].eq(project.try(:id))))
   end
 end
diff --git a/app/models/issue.rb b/app/models/issue.rb
index 4a4017003d8..6e8f5d3c422 100644
--- a/app/models/issue.rb
+++ b/app/models/issue.rb
@@ -266,7 +266,7 @@ class Issue < ActiveRecord::Base
 
   def as_json(options = {})
     super(options).tap do |json|
-      json[:subscribed] = subscribed?(options[:user]) if options.has_key?(:user) && options[:user]
+      json[:subscribed] = subscribed?(options[:user], project) if options.has_key?(:user) && options[:user]
 
       if options.has_key?(:labels)
         json[:labels] = labels.as_json(
diff --git a/app/models/subscription.rb b/app/models/subscription.rb
index 3b8aa1eb866..17869c8bac2 100644
--- a/app/models/subscription.rb
+++ b/app/models/subscription.rb
@@ -1,8 +1,9 @@
 class Subscription < ActiveRecord::Base
   belongs_to :user
+  belongs_to :project
   belongs_to :subscribable, polymorphic: true
 
-  validates :user_id,
-            uniqueness: { scope: [:subscribable_id, :subscribable_type] },
-            presence: true
+  validates :user, :subscribable, presence: true
+
+  validates :project_id, uniqueness: { scope: [:subscribable_id, :subscribable_type, :user_id] }
 end
diff --git a/app/services/issuable_base_service.rb b/app/services/issuable_base_service.rb
index bb92cd80cc9..575795788de 100644
--- a/app/services/issuable_base_service.rb
+++ b/app/services/issuable_base_service.rb
@@ -212,9 +212,9 @@ class IssuableBaseService < BaseService
   def change_subscription(issuable)
     case params.delete(:subscription_event)
     when 'subscribe'
-      issuable.subscribe(current_user)
+      issuable.subscribe(current_user, project)
     when 'unsubscribe'
-      issuable.unsubscribe(current_user)
+      issuable.unsubscribe(current_user, project)
     end
   end
 
diff --git a/app/services/notification_service.rb b/app/services/notification_service.rb
index 6697840cc26..ecdcbf08ee1 100644
--- a/app/services/notification_service.rb
+++ b/app/services/notification_service.rb
@@ -75,7 +75,7 @@ class NotificationService
   #  * watchers of the issue's labels
   #
   def relabeled_issue(issue, added_labels, current_user)
-    relabeled_resource_email(issue, added_labels, current_user, :relabeled_issue_email)
+    relabeled_resource_email(issue, issue.project, added_labels, current_user, :relabeled_issue_email)
   end
 
   # When create a merge request we should send an email to:
@@ -118,7 +118,7 @@ class NotificationService
   #  * watchers of the mr's labels
   #
   def relabeled_merge_request(merge_request, added_labels, current_user)
-    relabeled_resource_email(merge_request, added_labels, current_user, :relabeled_merge_request_email)
+    relabeled_resource_email(merge_request, merge_request.target_project, added_labels, current_user, :relabeled_merge_request_email)
   end
 
   def close_mr(merge_request, current_user)
@@ -205,7 +205,7 @@ class NotificationService
 
     recipients = reject_muted_users(recipients, note.project)
 
-    recipients = add_subscribed_users(recipients, note.noteable)
+    recipients = add_subscribed_users(recipients, note.project, note.noteable)
     recipients = reject_unsubscribed_users(recipients, note.noteable)
     recipients = reject_users_without_access(recipients, note.noteable)
 
@@ -393,7 +393,7 @@ class NotificationService
     )
   end
 
-  # Build a list of users based on project notifcation settings
+  # Build a list of users based on project notification settings
   def select_project_member_setting(project, global_setting, users_global_level_watch)
     users = notification_settings_for(project, :watch)
 
@@ -505,17 +505,17 @@ class NotificationService
     end
   end
 
-  def add_subscribed_users(recipients, target)
+  def add_subscribed_users(recipients, project, target)
     return recipients unless target.respond_to? :subscribers
 
-    recipients + target.subscribers
+    recipients + target.subscribers(project)
   end
 
-  def add_labels_subscribers(recipients, target, labels: nil)
+  def add_labels_subscribers(recipients, project, target, labels: nil)
     return recipients unless target.respond_to? :labels
 
     (labels || target.labels).each do |label|
-      recipients += label.subscribers
+      recipients += label.subscribers(project)
     end
 
     recipients
@@ -571,8 +571,8 @@ class NotificationService
     end
   end
 
-  def relabeled_resource_email(target, labels, current_user, method)
-    recipients = build_relabeled_recipients(target, current_user, labels: labels)
+  def relabeled_resource_email(target, project, labels, current_user, method)
+    recipients = build_relabeled_recipients(target, project, current_user, labels: labels)
     label_names = labels.map(&:name)
 
     recipients.each do |recipient|
@@ -608,10 +608,10 @@ class NotificationService
     end
 
     recipients = reject_muted_users(recipients, project)
-    recipients = add_subscribed_users(recipients, target)
+    recipients = add_subscribed_users(recipients, project, target)
 
     if [:new_issue, :new_merge_request].include?(custom_action)
-      recipients = add_labels_subscribers(recipients, target)
+      recipients = add_labels_subscribers(recipients, project, target)
     end
 
     recipients = reject_unsubscribed_users(recipients, target)
@@ -622,8 +622,8 @@ class NotificationService
     recipients.uniq
   end
 
-  def build_relabeled_recipients(target, current_user, labels:)
-    recipients = add_labels_subscribers([], target, labels: labels)
+  def build_relabeled_recipients(target, project, current_user, labels:)
+    recipients = add_labels_subscribers([], project, target, labels: labels)
     recipients = reject_unsubscribed_users(recipients, target)
     recipients = reject_users_without_access(recipients, target)
     recipients.delete(current_user)
diff --git a/app/services/slash_commands/interpret_service.rb b/app/services/slash_commands/interpret_service.rb
index 5a81194a5f4..d75c5b1800e 100644
--- a/app/services/slash_commands/interpret_service.rb
+++ b/app/services/slash_commands/interpret_service.rb
@@ -193,7 +193,7 @@ module SlashCommands
     desc 'Subscribe'
     condition do
       issuable.persisted? &&
-        !issuable.subscribed?(current_user)
+        !issuable.subscribed?(current_user, project)
     end
     command :subscribe do
       @updates[:subscription_event] = 'subscribe'
@@ -202,7 +202,7 @@ module SlashCommands
     desc 'Unsubscribe'
     condition do
       issuable.persisted? &&
-        issuable.subscribed?(current_user)
+        issuable.subscribed?(current_user, project)
     end
     command :unsubscribe do
       @updates[:subscription_event] = 'unsubscribe'
diff --git a/app/views/shared/_label.html.haml b/app/views/shared/_label.html.haml
index 6ccdef0df46..db324d8868e 100644
--- a/app/views/shared/_label.html.haml
+++ b/app/views/shared/_label.html.haml
@@ -1,6 +1,7 @@
 - label_css_id = dom_id(label)
 - open_issues_count = label.open_issues_count(current_user)
 - open_merge_requests_count = label.open_merge_requests_count(current_user)
+- status = label_subscription_status(label, @project).inquiry if current_user
 - subject = local_assigns[:subject]
 
 %li{id: label_css_id, data: { id: label.id } }
@@ -18,10 +19,19 @@
         %li
           = link_to_label(label, subject: subject) do
             = pluralize open_issues_count, 'open issue'
-        - if current_user
-          %li.label-subscription{ data: toggle_subscription_data(label) }
-            %a.js-subscribe-button.label-subscribe-button.subscription-status{ role: "button", href: "#", data: { toggle: "tooltip", status: label_subscription_status(label) } }
-              %span= label_subscription_toggle_button_text(label)
+        - if current_user && defined?(@project)
+          %li.label-subscription
+            - if label.is_a?(ProjectLabel)
+              %a.js-subscribe-button.label-subscribe-button{ role: 'button', href: '#', data: { status: status, url: toggle_subscription_namespace_project_label_path(@project.namespace, @project, label) } }
+                %span= label_subscription_toggle_button_text(label, @project)
+            - else
+              %a.js-unsubscribe-button.label-subscribe-button{ role: 'button', href: '#', class: ('hidden' if status.unsubscribed?), data: { url: group_label_unsubscribe_path(label, @project) } }
+                %span Unsubscribe
+              %a.js-subscribe-button.label-subscribe-button{ role: 'button', href: '#', class: ('hidden' unless status.unsubscribed?), data: { url: toggle_subscription_namespace_project_label_path(@project.namespace, @project, label) } }
+                %span Subscribe at project level
+              %a.js-subscribe-button.label-subscribe-button{ role: 'button', href: '#', class: ('hidden' unless status.unsubscribed?), data: { url: toggle_subscription_group_label_path(label.group, label) } }
+                %span Subscribe at group level
+
         - if can?(current_user, :admin_label, label)
           %li
             = link_to 'Edit', edit_label_path(label)
@@ -34,12 +44,27 @@
     = link_to_label(label, subject: subject, css_class: 'btn btn-transparent btn-action') do
       = pluralize open_issues_count, 'open issue'
 
-    - if current_user
-      .label-subscription.inline{ data: toggle_subscription_data(label) }
-        %button.js-subscribe-button.label-subscribe-button.btn.btn-transparent.btn-action.subscription-status{ type: "button", title: label_subscription_toggle_button_text(label), data: { toggle: "tooltip", status: label_subscription_status(label) } }
-          %span.sr-only= label_subscription_toggle_button_text(label)
-          = icon('eye', class: 'label-subscribe-button-icon', disabled: label.is_a?(GroupLabel))
-          = icon('spinner spin', class: 'label-subscribe-button-loading')
+    - if current_user && defined?(@project)
+      .label-subscription.inline
+        - if label.is_a?(ProjectLabel)
+          %button.js-subscribe-button.label-subscribe-button.btn.btn-default.btn-action{ type: 'button', title: label_subscription_toggle_button_text(label, @project), data: { toggle: 'tooltip', status: status, url: toggle_subscription_namespace_project_label_path(@project.namespace, @project, label) } }
+            %span= label_subscription_toggle_button_text(label, @project)
+            = icon('spinner spin', class: 'label-subscribe-button-loading')
+        - else
+          %button.js-unsubscribe-button.label-subscribe-button.btn.btn-default.btn-action{ type: 'button', class: ('hidden' if status.unsubscribed?), title: 'Unsubscribe', data: { toggle: 'tooltip', url: group_label_unsubscribe_path(label, @project) } }
+            %span Unsubscribe
+            = icon('spinner spin', class: 'label-subscribe-button-loading')
+
+          .dropdown.dropdown-group-label{ class: ('hidden' unless status.unsubscribed?) }
+            %button.dropdown-menu-toggle{type: 'button', 'data-toggle' => 'dropdown'}
+              %span Subscribe
+              = icon('chevron-down')
+            %ul.dropdown-menu
+              %li
+                %a.js-subscribe-button{ data: { url: toggle_subscription_namespace_project_label_path(@project.namespace, @project, label) } }
+                  Project level
+                %a.js-subscribe-button{ data: { url: toggle_subscription_group_label_path(label.group, label) } }
+                  Group level
 
     - if can?(current_user, :admin_label, label)
       = link_to edit_label_path(label), title: "Edit", class: 'btn btn-transparent btn-action', data: {toggle: "tooltip"} do
@@ -49,6 +74,10 @@
         %span.sr-only Delete
         = icon('trash-o')
 
-  - if current_user && label.is_a?(ProjectLabel)
-    :javascript
-      new Subscription('##{dom_id(label)} .label-subscription');
+  - if current_user && defined?(@project)
+    - if label.is_a?(ProjectLabel)
+      :javascript
+        new gl.ProjectLabelSubscription('##{dom_id(label)} .label-subscription');
+    - else
+      :javascript
+        new gl.GroupLabelSubscription('##{dom_id(label)} .label-subscription');
diff --git a/app/views/shared/issuable/_sidebar.html.haml b/app/views/shared/issuable/_sidebar.html.haml
index 7363ead09ff..f166fac105d 100644
--- a/app/views/shared/issuable/_sidebar.html.haml
+++ b/app/views/shared/issuable/_sidebar.html.haml
@@ -140,7 +140,7 @@
 
       = render "shared/issuable/participants", participants: issuable.participants(current_user)
       - if current_user
-        - subscribed = issuable.subscribed?(current_user)
+        - subscribed = issuable.subscribed?(current_user, @project)
         .block.light.subscription{data: {url: toggle_subscription_path(issuable)}}
           .sidebar-collapsed-icon
             = icon('rss')