Merge branch 'master' of https://github.com/bdurand/cocaine

README.md

@@ -119,6 +119,9 @@ But you don't have to, as you saw above where it doesn't use this. But you CAN l
 Cocaine::CommandLine.logger = Logger.new(STDOUT)
 Cocaine::CommandLine.new("date").run # => Logs this -> Command :: date
 ```
+## POSIX Spawn
+
+You can potentially increase performance by installing the posix-spawn gem (https://rubygems.org/gems/posix-spawn). This gem can keep your application's heap from being copied when forking command line processesG. For applications with large heaps the gain can be significant. To include posix-spawn, simply add it to your Gemfile or, if you don't use bundler, install the gem.
 
 ## License
 

cocaine.gemspec

@@ -20,5 +20,6 @@ Gem::Specification.new do |s|
   s.add_development_dependency('bourne')
   s.add_development_dependency('mocha')
   s.add_development_dependency('rake')
+  s.add_development_dependency('posix-spawn')
 end
 

lib/cocaine/command_line.rb

@@ -1,5 +1,13 @@
 module Cocaine
   class CommandLine
+    # Check for posix-spawn gem. If it is available it will prevent the invoked processes
+    # from getting a copy of the ruby heap which can lead to significant performance gains.
+    begin
+     require 'posix/spawn'
+    rescue LoadError => e
+      # posix-spawn gem not available
+    end
+
     class << self
       attr_accessor :path, :logger
     end
@@ -14,6 +22,7 @@ def initialize(binary, params = "", options = {})
       @swallow_stderr    = @options.delete(:swallow_stderr)
       @expected_outcodes = @options.delete(:expected_outcodes)
       @expected_outcodes ||= [0]
+      extend(POSIX::Spawn) if defined?(POSIX::Spawn)
     end
 
     def command
@@ -29,7 +38,7 @@ def run
       begin
         with_modified_path do
           @logger.info("\e[32mCommand\e[0m :: #{command}") if @logger
-          output = self.class.send(:'`', command)
+          output = send(:'`', command)
         end
       rescue Errno::ENOENT
         raise Cocaine::CommandNotFoundError

spec/cocaine/command_line_spec.rb

@@ -113,15 +113,15 @@
 
   it "runs the command it's given and return the output" do
     cmd = Cocaine::CommandLine.new("convert", "a.jpg b.png", :swallow_stderr => false)
-    cmd.class.stubs(:"`").with("convert a.jpg b.png").returns(:correct_value)
+    cmd.stubs(:"`").with("convert a.jpg b.png").returns(:correct_value)
     with_exitstatus_returning(0) do
       cmd.run.should == :correct_value
     end
   end
 
   it "raises a CommandLineError if the result code from the command isn't expected" do
     cmd = Cocaine::CommandLine.new("convert", "a.jpg b.png", :swallow_stderr => false)
-    cmd.class.stubs(:"`").with("convert a.jpg b.png").returns(:correct_value)
+    cmd.stubs(:"`").with("convert a.jpg b.png").returns(:correct_value)
     with_exitstatus_returning(1) do
       lambda do
         cmd.run
@@ -134,7 +134,7 @@
                                    "a.jpg b.png",
                                    :expected_outcodes => [0, 1],
                                    :swallow_stderr => false)
-    cmd.class.stubs(:"`").with("convert a.jpg b.png").returns(:correct_value)
+    cmd.stubs(:"`").with("convert a.jpg b.png").returns(:correct_value)
     with_exitstatus_returning(1) do
       lambda do
         cmd.run
@@ -184,4 +184,31 @@
     cmd = Cocaine::CommandLine.new("echo", "'Logging!'", :logger => nil)
     lambda { cmd.run }.should_not raise_error
   end
+
+  describe "command execution" do
+    it "should use the ` method to invoke the command line" do
+      cmd = Cocaine::CommandLine.new("echo", "hello")
+      cmd.stubs(:`).with(anything).returns(nil)
+      cmd.run
+      cmd.should have_received(:`).with("echo hello")
+    end
+
+    it "should use POSIX::Spawn to create processes if it is available" do
+      cmd = Cocaine::CommandLine.new("echo", "hello")
+      cmd.method(:`).owner.should == POSIX::Spawn
+      cmd.run.chomp.should == "hello"
+    end
+
+    it "should use the default Kernel spawning to create processes if POSIX::Spawn is not available" do
+      spawn = POSIX::Spawn
+      POSIX.send(:remove_const, :Spawn)
+      begin
+        cmd = Cocaine::CommandLine.new("echo", "hello")
+        cmd.method(:`).owner.should == Kernel
+        cmd.run.chomp.should == "hello"
+      ensure
+        POSIX.const_set(:Spawn, spawn)
+      end
+    end
+  end
 end