Rainbow extends ruby String class adding methods to wrap the string with ANSI escape codes.
Rainbow adds following methods to String class:
- foreground(color) (with color and colour aliases)
- italic (not well supported by terminal emulators).
Each of those methods returns string wrapped with some ANSI codes so you can chain calls as in example above.
Color can be one of following symbols:
:black, :red, :green, :yellow, :blue, :magenta, :cyan, :white, :default
If you have 256-colors capable terminal you can also specify color in RGB which will find the nearest match from 256 colors palette:
"Jolacz".color(115, 23, 98) "Jolacz".color("#FFC482") "Jolacz".color("FFC482")
For support on Windows, you should install the following gems:
gem install windows-pr win32console
If the gems aren't installed strings are simply returned unaltered.
Rainbow can be disabled globally by setting:
::. = false
It will be disabled by default if it detects that STDOUT is not a TTY.
gem install rainbow
require 'rainbow' puts "this is red".foreground(:red) + " and " + "this on yellow bg".background(:yellow) + " and " + "even bright underlined!".underline.bright
You're probably wanting to add colour to your logs. To do so you must explicity enable rainbow because it will detect that STDOUT (ie: the log file) is not a TTY.
To make things easy, create the file
config/initializers/rainbow.rb and include the following:
require 'rainbow' ::. = true
- Marcin Kulik
- Xavier Nayrac