Add connection_data method to Gitaly client

Backport of https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/7434

lib/gitlab/gitaly_client.rb

@@ -126,7 +126,11 @@ module Gitlab
     end
 
     def self.address_metadata(storage)
-      Base64.strict_encode64(JSON.dump({ storage => { 'address' => address(storage), 'token' => token(storage) } }))
+      Base64.strict_encode64(JSON.dump(storage => connection_data(storage)))
+    end
+
+    def self.connection_data(storage)
+      { 'address' => address(storage), 'token' => token(storage) }
     end
 
     # All Gitaly RPC call sites should use GitalyClient.call. This method

spec/lib/gitlab/gitaly_client_spec.rb

@@ -119,6 +119,15 @@ describe Gitlab::GitalyClient do
     end
   end
 
+  describe '.connection_data' do
+    it 'returns connection data' do
+      address = 'tcp://localhost:9876'
+      stub_repos_storages address
+
+      expect(described_class.connection_data('default')).to eq({ 'address' => address, 'token' => 'secret' })
+    end
+  end
+
   describe 'allow_n_plus_1_calls' do
     context 'when RequestStore is enabled', :request_store do
       it 'returns the result of the allow_n_plus_1_calls block' do