add ability to generate static gzip files

[beanieboi]

hey

i needed to generate static gzip files for nginx. here is the feature

thanks
ben

[ixti]

Thanks for your pull request. Can you please add tests?
Also I think there's no need to gzip JPEGs, so probably we can have configuration option as: list of mimetypes that are OK to be gzippable, true for default list of mimrtypes or false (default) for no gzipping at all.

[beanieboi]

hey @ixti

i added some basic test for the configuration option. i couldn't find any test for the generated files. did i miss something? please point me to some!

i'm not sure if if we need a list of mimetypes. i never had this setup where you enabled static gzip only for a few assets, it was always an all or nothing. (YMMV)
do you have suggestions for such a list?
i theory you are right, maybe its not worth compressing JPEGs (i have some which are reduced by 5-8% in file size) but i would suggest that we add this feature later, if there is a demand for this?

[ixti]

Well, I would set default list to js + css only, but I tend to agree that most of the time it's all or nothing. And we can add it once somebody will hit other than this requirement - leaving true/false for now. Well I can add test by myself, or you can add it close to this one:

https://github.com/ixti/jekyll-assets/blob/master/spec/lib/jekyll/assets_plugin/site_patch_spec.rb#L103

Also, make gzip false by default please. And if you can a small description in config would be highly appreciated :D

[beanieboi]

cool! i will add test and description!

[ixti]

Thanks! And then I'll publish fresh version!

[ixti]

Re what types to gzip. I think we will stick to the same logic as Sprockets does for it's manifest:
sstephenson/sprockets@eb84c41

In our case it would be something like:

class AssetFile
  # ...

  def write
    # ...
    @asset.write_to dest_path
    @asset.write_to "#{dest_path}.gz" if zip?
    # ...
  end

  def zip?
    @site.assets_config.gzip and @asset.is_a? Sprockets::BundledAsset
  end

  # ...
end

[ixti]

Thanks for your help.

[ixti]

After some considerations - I have made gzip options to be either an array of mime-types that should be gzipped (text/css and application/javascript by default) or boolean false to disable gzipping. Thanks for your work once again.