Rake task that can install gitaly at a tag version

lib/gitlab/gitaly_client.rb

@@ -2,6 +2,8 @@ require 'gitaly'
 module Gitlab
   module GitalyClient
+    SERVER_VERSION_FILE = 'GITALY_SERVER_VERSION'.freeze
+
     def self.gitaly_address
       if Gitlab.config.gitaly.socket_path
         "unix://#{Gitlab.config.gitaly.socket_path}"
@@ -39,5 +41,10 @@ module Gitlab
         yield is_enabled
       end
     end
+
+    def self.expected_server_version
+      path = Rails.root.join(SERVER_VERSION_FILE)
+      path.read.chomp
+    end
   end
 end

lib/tasks/gitlab/gitaly.rake

+namespace :gitlab do
+  namespace :gitaly do
+    desc "GitLab | Install or upgrade gitaly"
+    task :install, [:dir] => :environment do |t, args|
+      warn_user_is_not_gitlab
+      unless args.dir.present?
+        abort %(Please specify the directory where you want to install gitaly:\n  rake "gitlab:gitaly:install[/home/git/gitaly]")
+      end
+
+      tag = "v#{Gitlab::GitalyClient.expected_server_version}"
+      repo = 'https://gitlab.com/gitlab-org/gitaly.git'
+
+      checkout_or_clone_tag(tag: tag, repo: repo, target_dir: args.dir)
+
+      _, status = Gitlab::Popen.popen(%w[which gmake])
+      command = status.zero? ? 'gmake' : 'make'
+
+      Dir.chdir(args.dir) do
+        run_command!([command])
+      end
+    end
+  end
+end

spec/tasks/gitlab/gitaly_rake_spec.rb

+require 'rake_helper'
+
+describe 'gitlab:gitaly namespace rake task' do
+  before :all do
+    Rake.application.rake_require 'tasks/gitlab/gitaly'
+  end
+
+  describe 'install' do
+    let(:repo) { 'https://gitlab.com/gitlab-org/gitaly.git' }
+    let(:clone_path) { Rails.root.join('tmp/tests/gitaly').to_s }
+    let(:tag) { "v#{File.read(Rails.root.join(Gitlab::GitalyClient::SERVER_VERSION_FILE)).chomp}" }
+    before do
+      allow(ENV).to receive(:[])
+    end
+
+    context 'no dir given' do
+      it 'aborts and display a help message' do
+        # avoid writing task output to spec progress
+        allow($stderr).to receive :write
+        expect { run_rake_task('gitlab:gitaly:install') }.to raise_error /Please specify the directory where you want to install gitaly/
+      end
+    end
+
+    context 'when an underlying Git command fail' do
+      it 'aborts and display a help message' do
+        expect_any_instance_of(Object).
+          to receive(:checkout_or_clone_tag).and_raise 'Git error'
+
+        expect { run_rake_task('gitlab:gitaly:install', clone_path) }.to raise_error 'Git error'
+      end
+    end
+
+    describe 'checkout or clone' do
+      before do
+        expect(Dir).to receive(:chdir).with(clone_path)
+      end
+
+      it 'calls checkout_or_clone_tag with the right arguments' do
+        expect_any_instance_of(Object).
+          to receive(:checkout_or_clone_tag).with(tag: tag, repo: repo, target_dir: clone_path)
+
+        run_rake_task('gitlab:gitaly:install', clone_path)
+      end
+    end
+
+    describe 'gmake/make' do
+      before do
+        FileUtils.mkdir_p(clone_path)
+        expect(Dir).to receive(:chdir).with(clone_path).and_call_original
+      end
+
+      context 'gmake is available' do
+        before do
+          expect_any_instance_of(Object).to receive(:checkout_or_clone_tag)
+          allow_any_instance_of(Object).to receive(:run_command!).with(['gmake']).and_return(true)
+        end
+
+        it 'calls gmake in the gitaly directory' do
+          expect(Gitlab::Popen).to receive(:popen).with(%w[which gmake]).and_return(['/usr/bin/gmake', 0])
+          expect_any_instance_of(Object).to receive(:run_command!).with(['gmake']).and_return(true)
+
+          run_rake_task('gitlab:gitaly:install', clone_path)
+        end
+      end
+
+      context 'gmake is not available' do
+        before do
+          expect_any_instance_of(Object).to receive(:checkout_or_clone_tag)
+          allow_any_instance_of(Object).to receive(:run_command!).with(['make']).and_return(true)
+        end
+
+        it 'calls make in the gitaly directory' do
+          expect(Gitlab::Popen).to receive(:popen).with(%w[which gmake]).and_return(['', 42])
+          expect_any_instance_of(Object).to receive(:run_command!).with(['make']).and_return(true)
+
+          run_rake_task('gitlab:gitaly:install', clone_path)
+        end
+      end
+    end
+  end
+end