Add Geo::Fdw::Project registry model to avoid code duplication

With this change we can dry up finders avoiding  code duplication.

ee/app/finders/geo/legacy_project_registry_pending_verification_finder.rb

@@ -31,11 +31,9 @@ module Geo
 
     # rubocop:disable CodeReuse/ActiveRecord
     def registries_pending_verification
-      Geo::ProjectRegistry
-        .joins(Geo::Fdw::GeoNode.fdw_inner_join_projects)
-        .joins(Geo::Fdw::GeoNode.fdw_inner_join_repository_state)
-        .where(Geo::Fdw::GeoNode.fdw_registries_pending_verification)
-        .where(Geo::Fdw::Project.within_shard(shard_name))
+      Geo::ProjectRegistry.all
+        .merge(Geo::Fdw::ProjectRegistry.registries_pending_verification)
+        .merge(Geo::Fdw::ProjectRegistry.within_shards(shard_name))
         .limit(batch_size)
     end
     # rubocop:enable CodeReuse/ActiveRecord

ee/app/finders/geo/project_registry_pending_verification_finder.rb

@@ -17,17 +17,25 @@ module Geo
       @batch_size = batch_size
     end
 
+    # rubocop:disable CodeReuse/ActiveRecord
     def execute
+      return Geo::ProjectRegistry.none unless valid_shard?
+
       current_node.project_registries
-        .joins(Geo::Fdw::GeoNode.fdw_inner_join_projects)
-        .joins(Geo::Fdw::GeoNode.fdw_inner_join_repository_state)
-        .where(Geo::Fdw::GeoNode.fdw_registries_pending_verification)
-        .where(Geo::Fdw::Project.within_shard(shard_name))
+        .merge(Geo::Fdw::ProjectRegistry.registries_pending_verification)
+        .merge(Geo::Fdw::ProjectRegistry.within_shards(shard_name))
         .limit(batch_size)
     end
+    # rubocop:enable CodeReuse/ActiveRecord
 
     private
 
-    attr_reader :current_node, :shard_name,:batch_size
+    attr_reader :current_node, :shard_name, :batch_size
+
+    def valid_shard?
+      return true unless current_node.selective_sync_by_shards?
+
+      current_node.selective_sync_shards.include?(shard_name)
+    end
   end
 end

ee/app/models/geo/fdw/geo_node.rb

@@ -14,44 +14,6 @@ module Geo
       has_many :geo_node_namespace_links, class_name: 'Geo::Fdw::GeoNodeNamespaceLink'
       has_many :namespaces, class_name: 'Geo::Fdw::Namespace', through: :geo_node_namespace_links
 
-      def self.fdw_inner_join_projects
-        project_registries_table = Geo::ProjectRegistry.arel_table
-        fdw_projects_table = Geo::Fdw::Project.arel_table
-
-        project_registries_table
-          .join(fdw_projects_table, Arel::Nodes::InnerJoin)
-          .on(project_registries_table[:project_id].eq(fdw_projects_table[:id]))
-          .join_sources
-      end
-
-      def self.fdw_inner_join_repository_state
-        project_registries_table = Geo::ProjectRegistry.arel_table
-        fdw_repository_state_table = Geo::Fdw::ProjectRepositoryState.arel_table
-
-        project_registries_table
-          .join(fdw_repository_state_table, Arel::Nodes::InnerJoin)
-          .on(project_registries_table[:project_id].eq(fdw_repository_state_table[:project_id]))
-          .join_sources
-      end
-
-      def self.fdw_registries_pending_verification
-        fdw_repositories_pending_verification.or(fdw_wikis_pending_verification)
-      end
-
-      def self.fdw_repositories_pending_verification
-        fdw_repository_state_table = Geo::Fdw::ProjectRepositoryState.arel_table
-
-        Geo::ProjectRegistry.repositories_pending_verification
-          .and(fdw_repository_state_table[:repository_verification_checksum].not_eq(nil))
-      end
-
-      def self.fdw_wikis_pending_verification
-        fdw_repository_state_table = Geo::Fdw::ProjectRepositoryState.arel_table
-
-        Geo::ProjectRegistry.wikis_pending_verification
-          .and(fdw_repository_state_table[:wiki_verification_checksum].not_eq(nil))
-      end
-
       def project_registries
         return Geo::ProjectRegistry.all unless selective_sync?
 
@@ -67,11 +29,8 @@ module Geo
       private
 
       def registries_for_selected_namespaces
-        query = selected_namespaces_and_descendants
-
-        Geo::ProjectRegistry
-          .joins(self.class.fdw_inner_join_projects)
-          .where(fdw_projects_table.name => { namespace_id: query.select(:id) })
+        Geo::Fdw::ProjectRegistry
+          .within_namespaces(selected_namespaces_and_descendants.select(:id))
       end
 
       def selected_namespaces_and_descendants
@@ -98,13 +57,7 @@ module Geo
       end
 
       def registries_for_selected_shards
-        Geo::ProjectRegistry
-          .joins(self.class.fdw_inner_join_projects)
-          .where(fdw_projects_table.name => { repository_storage: selective_sync_shards })
-      end
-
-      def fdw_projects_table
-        Geo::Fdw::Project.arel_table
+        Geo::Fdw::ProjectRegistry.within_shards(selective_sync_shards)
       end
 
       def fdw_namespaces_table

ee/app/models/geo/fdw/project.rb

@@ -7,8 +7,6 @@ module Geo
 
       self.table_name = Gitlab::Geo::Fdw.foreign_table_name('projects')
 
-      scope :within_shard, -> (shard_name) { arel_table[:repository_storage].eq(shard_name) }
-
       class << self
         # Searches for a list of projects based on the query given in `query`.
         #

ee/app/models/geo/fdw/project_registry.rb

+# frozen_string_literal: true
+
+module Geo
+  module Fdw
+    class ProjectRegistry
+      class << self
+        def registries_pending_verification
+          Geo::ProjectRegistry
+            .joins(fdw_inner_join_projects)
+            .joins(fdw_inner_join_repository_state)
+            .where(repositories_pending_verification.or(wikis_pending_verification))
+        end
+
+        def within_namespaces(namespace_ids)
+          Geo::ProjectRegistry
+            .joins(fdw_inner_join_projects)
+            .where(fdw_projects_table.name => { namespace_id: namespace_ids })
+        end
+
+        def within_shards(shard_names)
+          Geo::ProjectRegistry
+            .joins(fdw_inner_join_projects)
+            .where(fdw_projects_table.name => { repository_storage: Array(shard_names) })
+        end
+
+        private
+
+        def project_registries_table
+          Geo::ProjectRegistry.arel_table
+        end
+
+        def fdw_projects_table
+          Geo::Fdw::Project.arel_table
+        end
+
+        def fdw_repository_state_table
+          Geo::Fdw::ProjectRepositoryState.arel_table
+        end
+
+        def fdw_inner_join_projects
+          project_registries_table
+            .join(fdw_projects_table, Arel::Nodes::InnerJoin)
+            .on(project_registries_table[:project_id].eq(fdw_projects_table[:id]))
+            .join_sources
+        end
+
+        def fdw_inner_join_repository_state
+          project_registries_table
+            .join(fdw_repository_state_table, Arel::Nodes::InnerJoin)
+            .on(project_registries_table[:project_id].eq(fdw_repository_state_table[:project_id]))
+            .join_sources
+        end
+
+        def repositories_pending_verification
+          Geo::ProjectRegistry.repositories_pending_verification
+            .and(fdw_repository_state_table[:repository_verification_checksum].not_eq(nil))
+        end
+
+        def wikis_pending_verification
+          Geo::ProjectRegistry.wikis_pending_verification
+            .and(fdw_repository_state_table[:wiki_verification_checksum].not_eq(nil))
+        end
+      end
+    end
+  end
+end