Rack middleware of Request Decompression (gzip or deflate).

request_decompressor.rb

require 'zlib'

module Rack
   class UnknownCompressMethod < StandardError; end

   class RequestDecompressor
      def initialize(app)
         @app = app
      end

      def call(env)
         req = Rack::Request.new(env)
         env['rack.input'] = decompress(req.body, env['HTTP_CONTENT_ENCODING'])
         @app.call(env)
      end

      def decompress(body, method)
         case method
         when 'gzip'
            Zlib::GzipReader.wrap(StringIO.new body.read)
         when 'deflate'
            StringIO.new(Zlib::Inflate.inflate(body.read))
         when nil
            body
         else # unknown compressing method
            raise Rack::UnknownCompressMethod.new("unknown compress method '#{method}'.")
         end
      end
   end
end