Support require directory for sidekiq-cluster

sidekiq-cluster now supports the same -r/--require option as Sidekiq
itself does. This is needed as Omnibus changes the working directory,
preventing us from properly starting the sidekiq processes.

lib/gitlab/sidekiq_cluster.rb

@@ -59,15 +59,17 @@ module Gitlab
     # queues - An Array containing Arrays. Each sub Array should specify the
     #          queues to use for a single process.
     #
+    # directory - The directory of the Rails application.
+    #
     # Returns an Array containing the PIDs of the started processes.
-    def self.start(queues, env)
-      queues.map { |pair| start_sidekiq(pair, env) }
+    def self.start(queues, env, directory = Dir.pwd)
+      queues.map { |pair| start_sidekiq(pair, env, directory) }
     end
 
     # Starts a Sidekiq process that processes _only_ the given queues.
     #
     # Returns the PID of the started process.
-    def self.start_sidekiq(queues, env)
+    def self.start_sidekiq(queues, env, directory = Dir.pwd)
       switches = queues.map { |q| "-q #{q},1" }
 
       pid = Process.spawn(

lib/gitlab/sidekiq_cluster/cli.rb

@@ -14,6 +14,7 @@ module Gitlab
         @alive = true
         @processes = []
         @logger = Logger.new(log_output)
+        @rails_path = Dir.pwd
 
         # Use a log format similar to Sidekiq to make parsing/grepping easier.
         @logger.formatter = proc do |level, date, program, message|
@@ -33,7 +34,7 @@ module Gitlab
 
         @logger.info("Starting cluster with #{queues.length} processes")
 
-        @processes = SidekiqCluster.start(queues, @environment)
+        @processes = SidekiqCluster.start(queues, @environment, @rails_path)
 
         write_pid
         trap_signals
@@ -88,6 +89,10 @@ module Gitlab
             @pid = pid
           end
 
+          opt.on('-r', '--require PATH', 'Location of the Rails application') do |path|
+            @rails_path = path
+          end
+
           opt.on('-i', '--interval INT', 'The number of seconds to wait between worker checks') do |int|
             @interval = int.to_i
           end

spec/lib/gitlab/sidekiq_cluster_spec.rb

@@ -58,12 +58,12 @@ describe Gitlab::SidekiqCluster do
   describe '.start' do
     it 'starts Sidekiq with the given queues and environment' do
       expect(described_class).to receive(:start_sidekiq).
-        ordered.with(%w(foo), :production)
+        ordered.with(%w(foo), :production, 'foo/bar')
 
       expect(described_class).to receive(:start_sidekiq).
-        ordered.with(%w(bar baz), :production)
+        ordered.with(%w(bar baz), :production, 'foo/bar')
 
-      described_class.start([%w(foo), %w(bar baz)], :production)
+      described_class.start([%w(foo), %w(bar baz)], :production, 'foo/bar')
     end
   end