Added Titan::System, Titan::Thread#used_cpu and Titan::Thread#used_me…

…mory

CHANGELOG.md

@@ -1,3 +1,10 @@
+## dev
+
+- Features
+
+  * Added Titan::System that provides common methods
+  * Added Titan::Thread#used\_cpu and Titan::Thread#used\_memory
+
 ## 0.3.0 (December 12, 2010)
 
 - Features

lib/titan.rb

@@ -2,5 +2,6 @@
 
 module Titan
   autoload :CLI,      "titan/cli"
+  autoload :System,   "titan/system"
   autoload :Thread,   "titan/thread"
 end

lib/titan/system.rb

@@ -0,0 +1,22 @@
+module Titan
+  class System
+    class << self
+      #
+      # Calls the ps function of the OS with a given command and process
+      # id
+      #
+      # E.g., if you want to get the used memory of a given process
+      # (pid=10), you can do this by:
+      #
+      #     Titan::System.ps('rss', 10).to_i
+      #
+      def ps(command, pid)
+        if pid > 0
+          `ps -o #{command}= -p #{pid}`
+        else
+          nil
+        end
+      end
+    end
+  end
+end

lib/titan/thread.rb

@@ -56,6 +56,22 @@ def pid_file
       File.expand_path(@id.to_s + ".pid", Titan::Thread::TITAN_DIRECTORY)
     end
 
+    #
+    # Returns the used memory
+    #
+    def used_memory
+      used_memory = Titan::System.ps('rss', @pid)
+      used_memory ? used_memory.to_i : nil
+    end
+
+    #
+    # Returns the used CPU
+    #
+    def used_cpu
+      used_cpu = Titan::System.ps('%cpu', @pid)
+      used_cpu ? used_cpu.to_f : nil
+    end
+
     #
     # Opens the pid file and save its pid in it
     #

lib/titan/version.rb

@@ -1,3 +1,3 @@
 module Titan
-  VERSION = "0.3.0"
+  VERSION = "0.4.0.dev"
 end

spec/titan/system_spec.rb

@@ -0,0 +1,17 @@
+require 'spec_helper'
+
+describe Titan::System do
+  describe ".ps" do
+    context "given a pid that is greater than 0" do
+      it "should return a String" do
+        Titan::System.ps('rss', 1).should be_a(String)
+      end
+    end
+
+    context "given a pid that is equal 0" do
+      it "should return nil" do
+        Titan::System.ps('rss', 0).should be_nil
+      end
+    end
+  end
+end

spec/titan/thread_spec.rb

@@ -102,6 +102,60 @@ def new_thread(id=nil)
     end
   end
 
+  describe "#used_memory" do
+    before(:each) do
+      @thread = new_thread
+    end
+
+    it "should call Titan::System.ps" do
+      Titan::System.should_receive(:ps)
+      @thread.used_memory
+    end
+
+    context "given a pid exists" do
+      before(:each) do
+        @thread.run
+      end
+
+      it "should return an Integer" do
+         @thread.used_memory.should be_an(Integer)
+      end
+    end
+
+    context "given no pid exists" do
+      it "should return nil" do
+        @thread.used_memory.should be_nil
+      end
+    end
+  end
+
+  describe "#used_cpu" do
+    before(:each) do
+      @thread = new_thread
+    end
+
+    it "should call Titan::System.ps" do
+      Titan::System.should_receive(:ps)
+      @thread.used_cpu
+    end
+
+    context "given a pid exists" do
+      before(:each) do
+        @thread.run
+      end
+
+      it "should return a Float" do
+         @thread.used_cpu.should be_an(Float)
+      end
+    end
+
+    context "given no pid exists" do
+      it "should return nil" do
+        @thread.used_cpu.should be_nil
+      end
+    end
+  end
+
   describe "#save" do
     before(:each) do
       @thread = new_thread