Load, parse and cascade CSS rule sets in Ruby.
If you are looking for a pure css stylesheet parser/tokenizer/lexer have a look at crass or syntax_tree-css
gem install css_parserYou initiate a document CssParser::Document.new and you can start to load it with css. Main methods to add css are: load_uri! (load url and follows @imports based on the full url), load_file! (loads file and follows @imports based on path from file imported) and load_string! (load a block of css). All of these apis tries to absolute all urls.
CssParser::Document -> Wrapper to holds all the rules on one block
CssParser::RuleSet -> Wrapper to hold each use like .a, .b { color: hotpink; }. notice this example has two selectors .a and .b
require 'css_parser'
include CssParser
document = CssParser::Document.new
document.load_uri!('http://example.com/styles/style.css')
document = CssParser::Document.new
document.load_uri!('file://home/user/styles/style.css')
# load a remote file, setting the base_uri and media_types
document.load_uri!('../style.css', {base_uri: 'http://example.com/styles/inc/', media_types: [:screen, :handheld]})
# load a local file, setting the base_dir and media_types
document.load_file!('print.css', '~/styles/', :print)
# load a string
document = CssParser::Document.new
document.load_string! 'a { color: hotpink; }'
# lookup a rule by a selector
document.find_by_selector('#content')
#=> 'font-size: 13px; line-height: 1.2;'
# lookup a rule by a selector and media type
document.find_by_selector('#content', [:screen, :handheld])
# iterate through selectors by media type
document.each_selector(:screen) do |selector, declarations, specificity|
...
end
# add a block of CSS
css = <<-EOT
body { margin: 0 1em; }
EOT
document.add_block!(css)
# output all CSS rules in a single stylesheet
document.to_s
=> #content { font-size: 13px; line-height: 1.2; }
body { margin: 0 1em; }
# capturing byte offsets within a file
document.load_uri!('../style.css', {base_uri: 'http://example.com/styles/inc/', capture_offsets: true)
content_rule = document.find_rule_sets(['#content']).first
content_rule.filename
#=> 'http://example.com/styles/styles.css'
content_rule.offset
#=> 10703..10752
# capturing byte offsets within a string
document.load_string!('a { color: hotpink; }', {filename: 'index.html', capture_offsets: true)
content_rule = document.find_rule_sets(['a']).first
content_rule.filename
#=> 'index.html'
content_rule.offset
#=> 0..21bundle
bundle exec rakeRuns on Ruby 3.0/JRuby 9.4 or above.
By Alex Dunae (dunae.ca, e-mail 'code' at the same domain), 2007-11.
License: MIT
Thanks to all the wonderful contributors for their updates.
Made on Vancouver Island.