Adding pidfile option

lib/sidekiq/cli.rb

@@ -29,6 +29,7 @@ module Sidekiq
     def parse(args=ARGV)
       Sidekiq::Util.logger
       parse_options(args)
+      write_pid
       validate!
       boot_system
     end
@@ -127,6 +128,10 @@ module Sidekiq
         o.on '-c', '--concurrency INT', "processor threads to use" do |arg|
           @options[:processor_count] = arg.to_i
         end
+
+        o.on '-p', '--pidfile PATH', "path to use" do |arg|
+          @options[:pidfile] = arg
+        end
       end
 
       @parser.banner = "sidekiq [options]"
@@ -137,5 +142,13 @@ module Sidekiq
       @parser.parse!(argv)
     end
 
+    def write_pid
+      if path = @options[:pidfile]
+        File.open(path, 'w') do |f|
+          f.puts Process.pid
+        end
+      end
+    end
+
   end
 end

test/test_cli.rb

@@ -1,5 +1,6 @@
 require 'helper'
 require 'sidekiq/cli'
+require 'tempfile'
 
 class TestCli < MiniTest::Unit::TestCase
   describe 'with cli' do
@@ -34,6 +35,28 @@ class TestCli < MiniTest::Unit::TestCase
       assert_equal %w(bar foo foo foo), @cli.options[:queues].sort
     end
 
+    describe 'with pidfile' do
+      before do
+        @tmp_file = Tempfile.new('sidekiq-test')
+        @tmp_path = @tmp_file.path
+        @tmp_file.close!
+        File.unlink @tmp_path if File.exist? @tmp_path
+        @cli.parse(['sidekiq', '-p', @tmp_path, '-r', './test/fake_env.rb'])
+      end
+
+      after do
+        File.unlink @tmp_path if File.exist? @tmp_path
+      end
+
+      it 'sets pidfile path' do
+        assert_equal @tmp_path, @cli.options[:pidfile]
+      end
+
+      it 'writes pidfile' do
+        assert_equal File.read(@tmp_path).strip.to_i, Process.pid
+      end
+    end
+
     def new_cli
       cli = Sidekiq::CLI.new
       def cli.die(code)