Test PostgreSQL 9.6 and postgres_fdw with Geo specs

.gitlab-ci.yml

@@ -69,6 +69,12 @@ stages:
     - redis:alpine
     - docker.elastic.co/elasticsearch/elasticsearch:5.5.2
 
+.use-pg-9-6: &use-pg-9-6
+  services:
+    - postgres:9.6
+    - redis:alpine
+    - docker.elastic.co/elasticsearch/elasticsearch:5.5.2
+
 .use-mysql: &use-mysql
   services:
     - mysql:latest
@@ -117,6 +123,17 @@ stages:
   <<: *use-pg
   <<: *except-docs
 
+.rspec-geo-pg-9-6: &rspec-metadata-pg-geo
+  <<: *use-pg-9-6
+  <<: *except-docs
+  stage: test
+  script:
+    - export NO_KNAPSACK=1
+    - export CACHE_CLASSES=true
+    - source scripts/prepare_postgres_fdw.sh
+    - scripts/gitaly-test-spawn
+    - bundle exec rspec --color --format documentation --tag geo spec/
+
 .rspec-metadata-mysql: &rspec-metadata-mysql
   <<: *rspec-metadata
   <<: *use-mysql
@@ -338,6 +355,8 @@ rspec-pg 22 25: *rspec-metadata-pg
 rspec-pg 23 25: *rspec-metadata-pg
 rspec-pg 24 25: *rspec-metadata-pg
 
+rspec-pg geo: *rspec-metadata-pg-geo
+
 rspec-mysql 0 25: *rspec-metadata-mysql
 rspec-mysql 1 25: *rspec-metadata-mysql
 rspec-mysql 2 25: *rspec-metadata-mysql

lib/gitlab/geo.rb

@@ -74,6 +74,18 @@ module Gitlab
       GeoNode.where(host: host, port: port).exists?
     end
 
+    def self.fdw?
+      self.cache_value(:geo_fdw?) do
+        ::Geo::BaseRegistry.connection.execute(
+          "SELECT COUNT(*) FROM information_schema.tables WHERE table_schema = '#{self.fdw_schema}' AND table_type = 'FOREIGN TABLE'"
+        ).first.fetch('count').to_i.positive?
+      end
+    end
+
+    def self.fdw_schema
+      'gitlab_secondary'.freeze
+    end
+
     def self.repository_sync_job
       Sidekiq::Cron::Job.find('geo_repository_sync_worker')
     end

scripts/prepare_postgres_fdw.sh

+#!/bin/bash
+
+psql -h postgres -U postgres gitlabhq_geo_test <<EOF
+CREATE EXTENSION postgres_fdw;
+CREATE SERVER gitlab_secondary FOREIGN DATA WRAPPER postgres_fdw OPTIONS (host 'localhost', dbname 'gitlabhq_test');
+CREATE USER MAPPING FOR current_user SERVER gitlab_secondary OPTIONS (user 'postgres', password '');
+CREATE SCHEMA gitlab_secondary;
+IMPORT FOREIGN SCHEMA public FROM SERVER gitlab_secondary INTO gitlab_secondary;
+GRANT USAGE ON FOREIGN SERVER gitlab_secondary TO current_user;
+EOF

spec/lib/gitlab/geo_spec.rb

 require 'spec_helper'
 
-describe Gitlab::Geo do
+describe Gitlab::Geo, :geo do
   include ::EE::GeoHelpers
 
   set(:primary_node)   { create(:geo_node, :primary) }
@@ -18,6 +18,26 @@ describe Gitlab::Geo do
     end
   end
 
+  describe 'fdw?' do
+    let(:fdw_check) { "SELECT COUNT(*) FROM information_schema.tables WHERE table_schema = 'gitlab_secondary' AND table_type = 'FOREIGN TABLE'" }
+
+    before do
+      allow(::Geo::BaseRegistry.connection).to receive(:execute).with(anything).and_call_original
+    end
+
+    it 'returns true when PostgreSQL FDW is enabled' do
+      expect(::Geo::BaseRegistry.connection).to receive(:execute).with(fdw_check).and_return([{ 'count' => 1 }])
+
+      expect(described_class.fdw?).to be_truthy
+    end
+
+    it 'returns false when PostgreSQL FDW is not enabled' do
+      expect(::Geo::BaseRegistry.connection).to receive(:execute).with(fdw_check).and_return([{ 'count' => 0 }])
+
+      expect(described_class.fdw?).to be_falsey
+    end
+  end
+
   describe 'primary?' do
     context 'when current node is a primary node' do
       it 'returns true' do

spec/spec_helper.rb

@@ -181,6 +181,10 @@ RSpec.configure do |config|
     example.run if Group.supports_nested_groups?
   end
 
+  config.around(:each, :geo) do |example|
+    example.run if Gitlab::Database.postgresql?
+  end
+
   config.around(:each, :postgresql) do |example|
     example.run if Gitlab::Database.postgresql?
   end

spec/workers/geo/file_download_dispatch_worker_spec.rb

 require 'spec_helper'
 
-describe Geo::FileDownloadDispatchWorker, :postgresql do
+describe Geo::FileDownloadDispatchWorker, :geo do
   include ::EE::GeoHelpers
 
   set(:primary)   { create(:geo_node, :primary, host: 'primary-geo-node') }