Refactor Geo::SelectiveSync concern

Since GitLab 13.2 we don't rely on FDW query/models

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

@@ -45,19 +45,21 @@ module Geo::SelectiveSync
   private
 
   def selected_namespaces_and_descendants
-    relation = selected_namespaces_and_descendants_cte.apply_to(namespaces_model.all)
-    read_only(relation)
+    relation = selected_namespaces_and_descendants_cte.apply_to(Namespace.all)
+    read_only_relation(relation)
   end
 
   def selected_namespaces_and_descendants_cte
+    namespaces_table = Namespace.arel_table
+
     cte = Gitlab::SQL::RecursiveCTE.new(:base_and_descendants)
 
     cte << geo_node_namespace_links
-      .select(geo_node_namespace_links_table[:namespace_id].as('id'))
+      .select(geo_node_namespace_links.arel_table[:namespace_id].as('id'))
       .except(:order)
 
     # Recursively get all the descendants of the base set.
-    cte << namespaces_model
+    cte << Namespace
       .select(namespaces_table[:id])
       .from([namespaces_table, cte.table])
       .where(namespaces_table[:parent_id].eq(cte.table[:id]))
@@ -67,8 +69,8 @@ module Geo::SelectiveSync
   end
 
   def selected_leaf_namespaces_and_ancestors
-    relation = selected_leaf_namespaces_and_ancestors_cte.apply_to(namespaces_model.all)
-    read_only(relation)
+    relation = selected_leaf_namespaces_and_ancestors_cte.apply_to(Namespace.all)
+    read_only_relation(relation)
   end
 
   # Returns a CTE selecting namespace IDs for selected shards
@@ -78,14 +80,16 @@ module Geo::SelectiveSync
   # namespace of every project in those shards. We must also sync every
   # ancestor of those namespaces.
   def selected_leaf_namespaces_and_ancestors_cte
+    namespaces_table = Namespace.arel_table
+
     cte = Gitlab::SQL::RecursiveCTE.new(:base_and_ancestors)
 
-    cte << namespaces_model
+    cte << Namespace
       .select(namespaces_table[:id], namespaces_table[:parent_id])
       .where(id: projects.select(:namespace_id))
 
     # Recursively get all the ancestors of the base set.
-    cte << namespaces_model
+    cte << Namespace
       .select(namespaces_table[:id], namespaces_table[:parent_id])
       .from([namespaces_table, cte.table])
       .where(namespaces_table[:id].eq(cte.table[:parent_id]))
@@ -94,36 +98,10 @@ module Geo::SelectiveSync
     cte
   end
 
-  def read_only(relation)
+  def read_only_relation(relation)
     # relations using a CTE are not safe to use with update_all as it will
     # throw away the CTE, hence we mark them as read-only.
     relation.extend(Gitlab::Database::ReadOnlyRelation)
     relation
   end
-
-  # This concern doesn't define a geo_node_namespace_links relation. That's
-  # done in ::GeoNode or ::Geo::Fdw::GeoNode respectively. So when we use the
-  # same code from the two places, they act differently - the first doesn't
-  # use FDW, the second does.
-  def geo_node_namespace_links_table
-    geo_node_namespace_links.arel_table
-  end
-
-  # This concern doesn't define a namespaces relation. That's done in ::GeoNode
-  # or ::Geo::Fdw::GeoNode respectively. So when we use the same code from the
-  # two places, they act differently - the first doesn't use FDW, the second does.
-  def namespaces_model
-    namespaces.model
-  end
-
-  # This concern doesn't define a namespaces relation. That's done in ::GeoNode
-  # or ::Geo::Fdw::GeoNode respectively. So when we use the same code from the
-  # two places, they act differently - the first doesn't use FDW, the second does.
-  def namespaces_table
-    namespaces.arel_table
-  end
-
-  def projects_table
-    Project.arel_table
-  end
 end