Automatically publish created events

For Models with Replicators that define the
"handle_after_create_commit" hook method.

ee/app/models/concerns/geo/blob_replicator_strategy.rb

@@ -11,8 +11,7 @@ module Geo
     class_methods do
     end
 
-    # Called by Packages::PackageFile on create
-    def publish_created_event
+    def handle_after_create_commit
       publish(:created, **created_params)
     end
 

ee/app/models/packages/package_file.rb

@@ -35,7 +35,6 @@ class Packages::PackageFile < ApplicationRecord
   with_replicator Geo::PackageFileReplicator
 
   after_save :update_file_metadata, if: :saved_change_to_file?
-  after_create_commit -> { replicator.publish_created_event }
 
   update_project_statistics project_statistics_name: :packages_size
 

ee/lib/gitlab/geo/replicable_model.rb

@@ -3,11 +3,14 @@
 module Gitlab
   module Geo
     module ReplicableModel
-      def self.included(klass)
-        klass.extend(ClassMethods)
+      extend ActiveSupport::Concern
+
+      included do
+        # If this hook turns out not to apply to all Models, perhaps we should extract a `ReplicableBlobModel`
+        after_create_commit -> { replicator.handle_after_create_commit if replicator.respond_to?(:handle_after_create_commit) }
       end
 
-      module ClassMethods
+      class_methods do
         def with_replicator(klass)
           raise ArgumentError, 'Must be a class inheriting from Gitlab::Geo::Replicator' unless klass < ::Gitlab::Geo::Replicator
 

ee/spec/lib/gitlab/geo/replicator_spec.rb

@@ -38,6 +38,10 @@ describe Gitlab::Geo::Replicator do
     context 'model DSL' do
       class DummyModel
         include ActiveModel::Model
+
+        def self.after_create_commit(*args)
+        end
+
         include Gitlab::Geo::ReplicableModel
 
         with_replicator DummyReplicator

spec/support/shared_examples/models/concerns/blob_replicator_strategy_shared_examples.rb

@@ -18,10 +18,10 @@ RSpec.shared_examples 'a blob replicator' do
     stub_current_geo_node(primary)
   end
 
-  describe '#publish_created_event' do
+  describe '#handle_after_create_commit' do
     it 'creates a Geo::Event' do
       expect do
-        replicator.publish_created_event
+        replicator.handle_after_create_commit
       end.to change { ::Geo::Event.count }.by(1)
 
       expect(::Geo::Event.last.attributes).to include(
@@ -60,5 +60,18 @@ RSpec.shared_examples 'a blob replicator' do
     it 'is a Class' do
       expect(invoke_model).to be_a(Class)
     end
+
+    # For convenience (and reliability), instead of asking developers to include shared examples on each model spec as well
+    context 'replicable model' do
+      it 'defines #replicator' do
+        expect(model_record).to respond_to(:replicator)
+      end
+
+      it 'invokes replicator.handle_after_create_commit on create' do
+        expect(replicator).to receive(:handle_after_create_commit)
+
+        model_record.save!
+      end
+    end
   end
 end