Resource event model

5 files changed, 96 insertions, 0 deletions

diff --git a/app/models/concerns/label_eventable.rb b/app/models/concerns/label_eventable.rb
new file mode 100644
index 00000000000..d22d93448e4
--- /dev/null
+++ b/app/models/concerns/label_eventable.rb
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+# == LabelEventable concern
+#
+# Contains functionality related to objects that support adding/removing labels.
+#
+# This concern is not used yet, it will be used for:
+# https://gitlab.com/gitlab-org/gitlab-ce/issues/48483
+
+module LabelEventable
+  extend ActiveSupport::Concern
+
+  included do
+    has_many :resource_label_events
+  end
+end
diff --git a/app/models/issue.rb b/app/models/issue.rb
index 4715d942c8d..e4ed06f9a69 100644
--- a/app/models/issue.rb
+++ b/app/models/issue.rb
@@ -12,6 +12,7 @@ class Issue < ActiveRecord::Base
   include TimeTrackable
   include ThrottledTouch
   include IgnorableColumn
+  include LabelEventable
 
   ignore_column :assignee_id, :branch_name, :deleted_at
 
diff --git a/app/models/merge_request.rb b/app/models/merge_request.rb
index b4090fd8baf..124ff6b3f91 100644
--- a/app/models/merge_request.rb
+++ b/app/models/merge_request.rb
@@ -10,6 +10,7 @@ class MergeRequest < ActiveRecord::Base
   include EachBatch
   include ThrottledTouch
   include Gitlab::Utils::StrongMemoize
+  include LabelEventable
 
   ignore_column :locked_at,
                 :ref_fetched,
diff --git a/app/models/resource_label_event.rb b/app/models/resource_label_event.rb
new file mode 100644
index 00000000000..42c255fcd1e
--- /dev/null
+++ b/app/models/resource_label_event.rb
@@ -0,0 +1,35 @@
+# frozen_string_literal: true
+
+# This model is not used yet, it will be used for:
+# https://gitlab.com/gitlab-org/gitlab-ce/issues/48483
+class ResourceLabelEvent < ActiveRecord::Base
+  belongs_to :user
+  belongs_to :issue
+  belongs_to :merge_request
+  belongs_to :label
+
+  validates :user, presence: true, on: :create
+  validates :label, presence: true, on: :create
+  validate :exactly_one_issuable
+
+  enum action: {
+    add: 1,
+    remove: 2
+  }
+
+  def self.issuable_columns
+    %i(issue_id merge_request_id).freeze
+  end
+
+  def issuable
+    issue || merge_request
+  end
+
+  private
+
+  def exactly_one_issuable
+    if self.class.issuable_columns.count { |attr| self[attr] } != 1
+      errors.add(:base, "Exactly one of #{self.class.issuable_columns.join(', ')} is required")
+    end
+  end
+end
diff --git a/app/services/resource_events/change_labels_service.rb b/app/services/resource_events/change_labels_service.rb
new file mode 100644
index 00000000000..8edb0ddb3ed
--- /dev/null
+++ b/app/services/resource_events/change_labels_service.rb
@@ -0,0 +1,43 @@
+# frozen_string_literal: true
+
+# This service is not used yet, it will be used for:
+# https://gitlab.com/gitlab-org/gitlab-ce/issues/48483
+module ResourceEvents
+  class ChangeLabelsService
+    attr_reader :resource, :user
+
+    def initialize(resource, user)
+      @resource, @user = resource, user
+    end
+
+    def execute(added_labels: [], removed_labels: [])
+      label_hash = {
+        resource_column(resource) => resource.id,
+        user_id: user.id,
+        created_at: Time.now
+      }
+
+      labels = added_labels.map do |label|
+        label_hash.merge(label_id: label.id, action: ResourceLabelEvent.actions['add'])
+      end
+      labels += removed_labels.map do |label|
+        label_hash.merge(label_id: label.id, action: ResourceLabelEvent.actions['remove'])
+      end
+
+      Gitlab::Database.bulk_insert(ResourceLabelEvent.table_name, labels)
+    end
+
+    private
+
+    def resource_column(resource)
+      case resource
+      when Issue
+        :issue_id
+      when MergeRequest
+        :merge_request_id
+      else
+        raise ArgumentError, "Unknown resource type #{resource.class.name}"
+      end
+    end
+  end
+end