Fix unicorn pid auto-detection behavior

lib/capistrano-unicorn/config.rb

@@ -36,16 +36,7 @@ def self.load(config)
           _cset(:unicorn_config_stage_file_path) \
             { app_path + '/' + unicorn_config_stage_rel_file_path }
           _cset(:unicorn_default_pid)        { app_path + "/tmp/pids/unicorn.pid" }
-          _cset(:unicorn_pid) do
-            extracted_pid = extract_pid_file
-            if extracted_pid
-              extracted_pid
-            else
-              logger.important "err :: failed to auto-detect pid from #{local_unicorn_config}"
-              logger.important "err :: falling back to default: #{unicorn_default_pid}"
-              unicorn_default_pid
-            end
-          end
+          _cset(:unicorn_pid) { extract_pid_file || unicorn_default_pid }
       end
     end
   end

lib/capistrano-unicorn/utility.rb

@@ -2,35 +2,20 @@ module CapistranoUnicorn
   module Utility
 
     def local_unicorn_config
-      File.exist?(unicorn_config_rel_file_path) ?
-          unicorn_config_rel_file_path
-        : unicorn_config_stage_rel_file_path
+      File.exist?(unicorn_config_file_path) ?
+          unicorn_config_file_path
+        : unicorn_config_stage_file_path
     end
 
     def extract_pid_file
-      tmp = Tempfile.new('unicorn.rb')
-      begin
-        conf = local_unicorn_config
-        tmp.write <<-EOF.gsub(/^ */, '')
-          config_file = "#{conf}"
-
-          # stub working_directory to avoid chdir failure since this will
-          # run client-side:
-          def working_directory(path); end
-
-          instance_eval(File.read(config_file), config_file) if config_file
-          puts set[:pid]
-          exit 0
-        EOF
-        tmp.close
-        extracted_pid = `unicorn -c "#{tmp.path}"`
-        $?.success? ? extracted_pid.rstrip : nil
-      rescue StandardError => e
-        return nil
-      ensure
-        tmp.close
-        tmp.unlink
-      end
+      code = <<-EOC.gsub(/^ */, '').gsub(/\n/, '; ')
+        cfg = Unicorn::Configurator.new(:config_file => '#{local_unicorn_config}')
+        puts cfg.set[:pid]
+        exit 0
+      EOC
+
+      pid = capture("cd #{current_path} && unicorn -e \"#{code}\"", :roles => unicorn_roles).rstrip
+      pid == "unset" ? nil : File.expand_path(pid, app_path)
     end
 
     # Check if a remote process exists using its pid file

spec/config_spec.rb

@@ -32,39 +32,23 @@
         end
 
         it "should default to a sensible pid file when auto-detection failed" do
-          @configuration.should_receive(shell).with(/unicorn -c /).and_return('') do |cmd|
-            `false` # Simulate failure by setting $?
-          end
+          @configuration.should_receive(:capture).and_return('unset')
           @configuration.logger.stub(:important)
           @configuration.fetch(:unicorn_pid).should == app_path + "/tmp/pids/unicorn.pid"
         end
 
-        shared_examples "auto-detect pid file from unicorn config" do
-          |pid_file, primary_exists, config_file|
-          which_config = primary_exists ? 'primary' : 'stage'
-          it "should auto-detect pid file from #{which_config} unicorn config" do
-            # Tempfile.new in Ruby 1.9.2 will call File.exist?
-            allow(File).to receive(:exist?).with(/tmp/)
-
-            File.should_receive(:exist?).with('config/unicorn.rb').and_return(primary_exists)
-            tmpfile = nil
-            @configuration.should_receive(shell).with(/unicorn -c /) do |cmd|
-              (cmd =~ /^unicorn -c "(.+)"$/).should be_true
-              tmpfile = $~[1]
-              tmpfile.should include("tmp")
-              File.read(tmpfile).should include(%!config_file = "#{config_file}"!)
-              `true` # Simulate success by setting $?
-              pid_file
-            end
-            @configuration.fetch(:unicorn_pid).should == pid_file
+        shared_examples "auto-detect pid file from unicorn config" do |pid_file|
+          it "should auto-detect pid file from unicorn config" do
+            @configuration.should_receive(:capture).and_return(pid_file)
+            @configuration.fetch(:unicorn_pid).should == File.expand_path(pid_file, app_path)
           end
         end
 
         include_examples "auto-detect pid file from unicorn config", \
-          '/path/to/pid/from/config/file', true, "config/unicorn.rb"
+          '/path/to/pid/from/config/file'
 
         include_examples "auto-detect pid file from unicorn config", \
-          '/path/to/pid/from/stage/config/file', false, "config/unicorn/production.rb"
+          'relative/path/to/pid'
 
         specify "Gemfile should default correctly" do
           @configuration.fetch(:bundle_gemfile).should == app_path + "/Gemfile"