Remove ES parent relation for project snippets

https://gitlab.com/gitlab-org/gitlab/merge_requests/18459 added a join
relation on project snippets to support searching public/internal
projects.

Since this requires recreating the index this broke indexing on existing
indices, so we decided to revert this change for now.

We're keeping most of the changes from the original MR since it also
refactored the ES snippet classes to align with the other models.

ee/changelogs/unreleased/34558-revert-es-project-snippets.yml

+---
+title: Revert ES support for public/internal project snippets
+merge_request: 19715
+author:
+type: fixed

ee/lib/elastic/latest/config.rb

@@ -66,7 +66,6 @@ module Elastic
               blob
               wiki_blob
               commit
-              snippet
             )
           }
         # ES6 requires a single type per index, so we implement our own "type"

ee/lib/elastic/latest/snippet_class_proxy.rb

@@ -74,28 +74,6 @@ module Elastic
 
         filter_conditions = []
 
-        # Include public/internal project snippets for accessible projects
-        filter_conditions << {
-          bool: {
-            filter: [
-              { terms: { visibility_level: Gitlab::VisibilityLevel.levels_for_user(user) } },
-              {
-                has_parent: {
-                  parent_type: 'project',
-                  query: {
-                    bool: project_ids_query(
-                      user,
-                      options[:project_ids],
-                      options[:public_and_internal_projects],
-                      'snippets'
-                    )
-                  }
-                }
-              }
-            ]
-          }
-        }
-
         # Include all project snippets for authorized projects
         if user
           filter_conditions << {

ee/lib/elastic/latest/snippet_instance_proxy.rb

@@ -30,6 +30,12 @@ module Elastic
 
         data.merge(generic_attributes)
       end
+
+      # TODO: Reenable support for public/internal project snippets
+      # https://gitlab.com/gitlab-org/gitlab/issues/2358
+      def es_parent
+        nil
+      end
     end
   end
 end

ee/spec/features/search/elastic/snippet_search_spec.rb

@@ -2,7 +2,7 @@
 
 require 'spec_helper'
 
-describe 'Snippet elastic search', :js, :elastic, :sidekiq_might_not_need_inline do
+describe 'Snippet elastic search', :js, :elastic, :aggregate_failures, :sidekiq_might_not_need_inline do
   let(:public_project) { create(:project, :public) }
   let(:authorized_user) { create(:user) }
   let(:authorized_project) { create(:project, namespace: authorized_user.namespace) }
@@ -31,13 +31,16 @@ describe 'Snippet elastic search', :js, :elastic, :sidekiq_might_not_need_inline
     submit_search('snippet')
   end
 
+  # TODO: Reenable support for public/internal project snippets
+  # https://gitlab.com/gitlab-org/gitlab/issues/35760
+
   context 'as anonymous user' do
     let(:current_user) { nil }
 
     it 'finds only public snippets' do
       within('.results') do
         expect(page).to have_content('public personal snippet')
-        expect(page).to have_content('public project snippet')
+        expect(page).not_to have_content('public project snippet')
 
         expect(page).not_to have_content('internal personal snippet')
         expect(page).not_to have_content('internal project snippet')
@@ -57,10 +60,10 @@ describe 'Snippet elastic search', :js, :elastic, :sidekiq_might_not_need_inline
     it 'finds only public and internal snippets' do
       within('.results') do
         expect(page).to have_content('public personal snippet')
-        expect(page).to have_content('public project snippet')
+        expect(page).not_to have_content('public project snippet')
 
         expect(page).to have_content('internal personal snippet')
-        expect(page).to have_content('internal project snippet')
+        expect(page).not_to have_content('internal project snippet')
 
         expect(page).not_to have_content('private personal snippet')
         expect(page).not_to have_content('private project snippet')
@@ -77,10 +80,10 @@ describe 'Snippet elastic search', :js, :elastic, :sidekiq_might_not_need_inline
     it 'finds only public, internal, and authorized private snippets' do
       within('.results') do
         expect(page).to have_content('public personal snippet')
-        expect(page).to have_content('public project snippet')
+        expect(page).not_to have_content('public project snippet')
 
         expect(page).to have_content('internal personal snippet')
-        expect(page).to have_content('internal project snippet')
+        expect(page).not_to have_content('internal project snippet')
 
         expect(page).not_to have_content('private personal snippet')
         expect(page).not_to have_content('private project snippet')

ee/spec/models/concerns/elastic/snippet_spec.rb

@@ -137,11 +137,7 @@ describe Snippet, :elastic do
       'author_id',
       'visibility_level'
     ).merge({
-      'type' => snippet.es_type,
-      'join_field' => {
-        'name' => snippet.es_type,
-        'parent' => snippet.es_parent
-      }
+      'type' => snippet.es_type
     })
 
     expect(snippet.__elasticsearch__.as_indexed_json).to eq(expected_hash)

ee/spec/services/elastic/index_record_service_spec.rb

@@ -101,8 +101,7 @@ describe Elastic::IndexRecordService, :elastic do
         'issue',
         'merge_request',
         'milestone',
-        'note',
-        'snippet'
+        'note'
       )
     end