Use ResourceLabelEvent for tracking label changes

5 files changed, 91 insertions, 0 deletions

diff --git a/lib/api/api.rb b/lib/api/api.rb
index 843f75d3096..e89d9337853 100644
--- a/lib/api/api.rb
+++ b/lib/api/api.rb
@@ -118,6 +118,7 @@ module API
     mount ::API::Namespaces
     mount ::API::Notes
     mount ::API::Discussions
+    mount ::API::ResourceLabelEvents
     mount ::API::NotificationSettings
     mount ::API::PagesDomains
     mount ::API::Pipelines
diff --git a/lib/api/entities.rb b/lib/api/entities.rb
index 90abee94f6a..f0eafbaeb94 100644
--- a/lib/api/entities.rb
+++ b/lib/api/entities.rb
@@ -1437,5 +1437,19 @@ module API
         badge.type == 'ProjectBadge' ? 'project' : 'group'
       end
     end
+
+    class ResourceLabelEvent < Grape::Entity
+      expose :id
+      expose :user, using: Entities::UserBasic
+      expose :created_at
+      expose :resource_type do |event, options|
+        event.issuable.class.name
+      end
+      expose :resource_id do |event, options|
+        event.issuable.id
+      end
+      expose :label, using: Entities::LabelBasic
+      expose :action
+    end
   end
 end
diff --git a/lib/api/resource_label_events.rb b/lib/api/resource_label_events.rb
new file mode 100644
index 00000000000..5ac3adeb990
--- /dev/null
+++ b/lib/api/resource_label_events.rb
@@ -0,0 +1,52 @@
+# frozen_string_literal: true
+
+module API
+  class ResourceLabelEvents < Grape::API
+    include PaginationParams
+    helpers ::API::Helpers::NotesHelpers
+
+    before { authenticate! }
+
+    EVENTABLE_TYPES = [Issue, MergeRequest].freeze
+
+    EVENTABLE_TYPES.each do |eventable_type|
+      parent_type = eventable_type.parent_class.to_s.underscore
+      eventables_str = eventable_type.to_s.underscore.pluralize
+
+      params do
+        requires :id, type: String, desc: "The ID of a #{parent_type}"
+      end
+      resource parent_type.pluralize.to_sym, requirements: API::PROJECT_ENDPOINT_REQUIREMENTS do
+        desc "Get a list of #{eventable_type.to_s.downcase} resource label events" do
+          success Entities::ResourceLabelEvent
+          detail 'This feature was introduced in 11.3'
+        end
+        params do
+          requires :eventable_id, types: [Integer, String], desc: 'The ID of the eventable'
+          use :pagination
+        end
+        get ":id/#{eventables_str}/:eventable_id/resource_label_events" do
+          eventable = find_noteable(parent_type, eventables_str, params[:eventable_id])
+          events = eventable.resource_label_events.includes(:label, :user)
+
+          present paginate(events), with: Entities::ResourceLabelEvent
+        end
+
+        desc "Get a single #{eventable_type.to_s.downcase} resource label event" do
+          success Entities::ResourceLabelEvent
+          detail 'This feature was introduced in 11.3'
+        end
+        params do
+          requires :event_id, type: String, desc: 'The ID of a resource label event'
+          requires :eventable_id, types: [Integer, String], desc: 'The ID of the eventable'
+        end
+        get ":id/#{eventables_str}/:eventable_id/resource_label_events/:event_id" do
+          eventable = find_noteable(parent_type, eventables_str, params[:eventable_id])
+          event = eventable.resource_label_events.find(params[:event_id])
+
+          present event, with: Entities::ResourceLabelEvent
+        end
+      end
+    end
+  end
+end
diff --git a/lib/banzai/pipeline/label_pipeline.rb b/lib/banzai/pipeline/label_pipeline.rb
new file mode 100644
index 00000000000..725cccc4b2b
--- /dev/null
+++ b/lib/banzai/pipeline/label_pipeline.rb
@@ -0,0 +1,14 @@
+# frozen_string_literal: true
+
+module Banzai
+  module Pipeline
+    class LabelPipeline < BasePipeline
+      def self.filters
+        @filters ||= FilterArray[
+          Filter::SanitizationFilter,
+          Filter::LabelReferenceFilter
+        ]
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/import_export/import_export.yml b/lib/gitlab/import_export/import_export.yml
index f030edc7d22..a19b3c88627 100644
--- a/lib/gitlab/import_export/import_export.yml
+++ b/lib/gitlab/import_export/import_export.yml
@@ -19,6 +19,9 @@ project_tree:
     - milestone:
       - events:
         - :push_event_payload
+    - resource_label_events:
+      - label:
+          :priorities
     - :issue_assignees
   - snippets:
     - :award_emoji
@@ -45,6 +48,9 @@ project_tree:
     - milestone:
       - events:
         - :push_event_payload
+    - resource_label_events:
+      - label:
+          :priorities
   - pipelines:
     - notes:
       - :author
@@ -137,6 +143,10 @@ excluded_attributes:
     - :event_id
   project_badges:
     - :group_id
+  resource_label_events:
+    - :reference
+    - :reference_html
+    - :epic_id
 
 methods:
   labels: