Htmlcompressor

Put your html on a diet

Htmlcompressor provides tools to minify html code. It includes

HtmlCompressor::Compressor class which is a raw port of google's htmlcompressor
HtmlCompressor::Rack a rack middleware to compress html pages on the fly. Beware that the compressor has proved to be too slow in many circunstances to be used for on the fly or real time execution. I encourage you to use it only for build-time optimisations or decrease the number of optimisations that are run at execution time.

Please note that Htmlcompressor is still in alpha version and need some additional love.

Usage

Using the compressor class is straightforward:

  compressor = HtmlCompressor::Compressor.new
  compressor.compress('<html><body><div id="compress_me"></div></body></html>')

The compressor ships with basic and safe default options that may be overwritten passing the options hash to the constructor:

options = {
  :enabled => true,
  :remove_spaces_inside_tags => true,
  :remove_multi_spaces => true,
  :remove_comments => true,
  :remove_intertag_spaces => false,
  :remove_quotes => false,
  :compress_css => false,
  :compress_javascript => false,
  :simple_doctype => false,
  :remove_script_attributes => false,
  :remove_style_attributes => false,
  :remove_link_attributes => false,
  :remove_form_attributes => false,
  :remove_input_attributes => false,
  :remove_javascript_protocol => false,
  :remove_http_protocol => false,
  :remove_https_protocol => false,
  :preserve_line_breaks => false,
  :simple_boolean_attributes => false,
  :compress_js_templates => false
}

Htmlcompressor also ships a rack middleware that can be used with rails, sinatra or rack.

However keep in mind that compression is slow (especially when also compressing javascript or css) and can negatively impact the performance of your website. Take your measurements and adopt a different strategy if necessary

Using rack middleware (in rails) is as easy as:

config.middleware.use HtmlCompressor::Rack, options

And in sinatra:

use HtmlCompressor::Rack, options

The middleware uses a little more aggressive options by default:

options = {
  :enabled => true,
  :remove_multi_spaces => true,
  :remove_comments => true,
  :remove_intertag_spaces => false,
  :remove_quotes => true,
  :compress_css => false,
  :compress_javascript => false,
  :simple_doctype => false,
  :remove_script_attributes => true,
  :remove_style_attributes => true,
  :remove_link_attributes => true,
  :remove_form_attributes => false,
  :remove_input_attributes => true,
  :remove_javascript_protocol => true,
  :remove_http_protocol => false,
  :remove_https_protocol => false,
  :preserve_line_breaks => false,
  :simple_boolean_attributes => true
}

Rails 2.3 users may need to add

require 'htmlcompressor'

Javascript template compression

You can compress javascript templates that are present in the html. Setting the :compress_js_templates options to true will by default compress the content of script tags marked with type="text/x-jquery-tmpl". For compressing other types of templates, you can pass a string (or an array of strings) containing the type: :compress_js_templates => ['text/html']. Please note that activating template compression will disable the removal of quotes from attributes values, as this could lead to unexpected errors with compiled templates.

Custom preservation rules

If you need to define custom preservation rules, you can list regular expressions in the preserve_patterns option. For example, to preserve PHP blocks you might want to define:

options = {
  :preserve_patterns => [/<\?php.*?\?>/im]
}

CSS and JavaScript Compression

By default CSS/JS compression is disabled. In order to minify in page javascript and css, you need to supply a compressor in the options hash. A compressor can be :yui or :closure or any object that responds to :compress. E.g.: compressed = compressor.compress(source)

class MyCompressor

  def compress(source)
    return 'minified'
  end

end

options = {
  :compress_css => true,
  :css_compressor => MyCompressor.new,
  :compress_javascript => true,
  :javascript_compressor => MyCompressor.new
}

Please note that in order to use yui or closure compilers you need to manually add them to the Gemfile

gem 'yui-compressor'

...

options = {
  :compress_javascript => true,
  :javascript_compressor => :yui,
  :compress_css => true,
  :css_compressor => :yui
}

gem 'closure-compiler'

...

options = {
  :compress_javascript => true,
  :javascript_compressor => :closure
}

Statistics

As of now the statistic framework hasn't been ported. Refer to original htmlcompressor documentation for statistics on minified pages.

License

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

Contributing

Fork it
Create your feature branch (git checkout -b my-new-feature)
Commit your changes (git commit -am 'Added some feature')
Push to the branch (git push origin my-new-feature)
Create new Pull Request

htmlcompressor

Development