Colorize Output

This change adds some color to the staging output.  Specifically it highlights
the component names, versions, and download times to make them more apparent
in logs.

Note this is a first attempt and the color scheme may be updated as better
alternatives are found.

Author: nebhale

lib/java_buildpack/buildpack_version.rb

@@ -14,6 +14,7 @@
 # limitations under the License.
 
 require 'java_buildpack'
+require 'java_buildpack/util/colorize'
 require 'java_buildpack/util/configuration_utils'
 require 'java_buildpack/util/to_b'
 

lib/java_buildpack/component/base_component.rb

@@ -90,7 +90,12 @@ def download(version, uri, name = @component_name)
         print "#{'----->'.red.bold} Downloading #{name.blue.bold} #{version.to_s.blue} from #{uri.sanitize_uri} "
 
         JavaBuildpack::Util::Cache::ApplicationCache.new.get(uri) do |file, downloaded|
-          puts downloaded ? "(#{(Time.now - download_start_time).duration})".green.italic : '(found in cache)'.green.italic
+          if downloaded
+            puts "(#{(Time.now - download_start_time).duration})".green.italic
+          else
+            puts '(found in cache)'.green.italic
+          end
+
           yield file
         end
       end

lib/java_buildpack/util/colorize.rb

@@ -15,88 +15,136 @@
 
 class String
 
-  def bg_black
-    "\e[40m#{self}\e[0m"
+  @color_enabled = true
+
+  class << self
+    attr_accessor :color_enabled
   end
 
-  def bg_blue
-    "\e[44m#{self}\e[0m"
+  # Sets the string to bold
+  def bold
+    return self unless @color_enabled
+    "\e[1m#{self}\e[22m"
   end
 
-  def bg_brown
-    "\e[43m#{self}\e[0m"
+  # Sets the string to italic
+  def italic
+    return self unless @color_enabled
+    "\e[3m#{self}\e[23m"
   end
 
-  def bg_cyan
-    "\e[46m#{self}\e[0m"
+  # Sets the string to underlined
+  def underline
+    return self unless @color_enabled
+    "\e[4m#{self}\e[24m"
   end
 
-  def bg_gray
-    "\e[47m#{self}\e[0m"
+  # Sets the string to blink
+  def blink
+    return self unless @color_enabled
+    "\e[5m#{self}\e[25m"
   end
 
-  def bg_green
-    "\e[42m#{self}\e[0m"
+  # Sets the string reverse the current colors
+  def reverse_color
+    return self unless @color_enabled
+    "\e[7m#{self}\e[27m"
   end
 
-  def bg_magenta
-    "\e[45m#{self}\e[0m"
+  # Sets the string to black
+  def black
+    return self unless @color_enabled
+    "\e[30m#{self}\e[0m"
   end
 
-  def bg_red
-    "\e[41m#{self}\e[0m"
+  # Sets the string to red
+  def red
+    return self unless @color_enabled
+    "\e[31m#{self}\e[0m"
   end
 
-  def black
-    "\e[30m#{self}\e[0m"
+  # Sets the string to green
+  def green
+    return self unless @color_enabled
+    "\e[32m#{self}\e[0m"
   end
 
-  def blink
-    "\e[5m#{self}\e[25m"
+  # Sets the string to yellow
+  def yellow
+    return self unless @color_enabled
+    "\e[33m#{self}\e[0m"
   end
 
+  # Sets the string to blue
   def blue
+    return self unless @color_enabled
     "\e[34m#{self}\e[0m"
   end
 
-  def bold
-    "\e[1m#{self}\e[22m"
-  end
-
-  def brown
-    "\e[33m#{self}\e[0m"
+  # Sets the string to magenta
+  def magenta
+    return self unless @color_enabled
+    "\e[35m#{self}\e[0m"
   end
 
+  # Sets the string to cyan
   def cyan
+    return self unless @color_enabled
     "\e[36m#{self}\e[0m"
   end
 
-  def gray
+  # Sets the string to white
+  def white
+    return self unless @color_enabled
     "\e[37m#{self}\e[0m"
   end
 
-  def green
-    "\e[32m#{self}\e[0m"
+  # Sets the string background to black
+  def bg_black
+    return self unless @color_enabled
+    "\e[40m#{self}\e[0m"
   end
 
-  def italic
-    "\e[3m#{self}\e[23m"
+  # Sets the string background to red
+  def bg_red
+    return self unless @color_enabled
+    "\e[41m#{self}\e[0m"
   end
 
-  def magenta
-    "\e[35m#{self}\e[0m"
+  # Sets the string background to green
+  def bg_green
+    return self unless @color_enabled
+    "\e[42m#{self}\e[0m"
   end
 
-  def red
-    "\e[31m#{self}\e[0m"
+  # Sets the string background to yellow
+  def bg_yellow
+    return self unless @color_enabled
+    "\e[43m#{self}\e[0m"
   end
 
-  def reverse_color
-    "\e[7m#{self}\e[27m"
+  # Sets the string background to blue
+  def bg_blue
+    return self unless @color_enabled
+    "\e[44m#{self}\e[0m"
   end
 
-  def underline
-    "\e[4m#{self}\e[24m"
+  # Sets the string background to magenta
+  def bg_magenta
+    return self unless @color_enabled
+    "\e[45m#{self}\e[0m"
+  end
+
+  # Sets the string background to cyan
+  def bg_cyan
+    return self unless @color_enabled
+    "\e[46m#{self}\e[0m"
+  end
+
+  # Sets the string background to white
+  def bg_white
+    return self unless @color_enabled
+    "\e[47m#{self}\e[0m"
   end
 
-end
+end

spec/console_helper.rb

@@ -15,6 +15,7 @@
 
 require 'spec_helper'
 require 'tee'
+require 'java_buildpack/util/colorize'
 
 shared_context 'console_helper' do
 
@@ -32,6 +33,8 @@
       $stdout.add STDOUT
       $stderr.add STDERR
     end
+
+    String.color_enabled = false
   end
 
   after do

spec/java_buildpack/buildpack_version_spec.rb

@@ -21,6 +21,7 @@
 
 describe JavaBuildpack::BuildpackVersion do
   include_context 'application_helper'
+  include_context 'console_helper'
   include_context 'logging_helper'
 
   let(:buildpack_version) { described_class.new }