Set compression level when generating a ZIP file using RubyZip

Question

I have a Ruby program that zips a directory tree of XML files using the rubyzip gem. My problem is that the file is starting to be heavy and I would like to increase the compression level, since compression time is not an issue.

I could not find in the rubyzip documentation a way to specify the compression level for the created ZIP file.

Anyone know how to change this setting? Is there another Ruby library that allows to specify compression level?

Answer 1

Here is the code I created by looking at rubyzip internal.

level = Zlib::BEST_COMPRESSION
Zip::ZipOutputStream.open(zip_file) do |zip|
    Dir.glob("**/*") do |filename|
        entry = Zip::ZipEntry.new("", filename)
        entry.gather_fileinfo_from_srcpath(filename)
        zip.put_next_entry(entry, nil, nil, Zip::ZipEntry::DEFLATED, level)
        entry.get_input_stream { |is| IOExtras.copy_stream(zip, is) }
    end
end

Answer 2

you'll probably get better traction by calling out to the 'zip' program or what not to do the zipping.