lib/falcon/adapters/rewindable.rb



# Copyright, 2018, by Samuel G. D. Williams. <http://www.codeotaku.com>
# 
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
# 
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
# 
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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# THE SOFTWARE.

require 'async/http/body/rewindable'

module Falcon
	module Adapters
		# Content type driven input buffering.
		class Rewindable < Async::HTTP::Middleware
			BUFFERED_MEDIA_TYPES = %r{
				application/x-www-form-urlencoded|
				multipart/form-data|
				multipart/related|
				multipart/mixed
			}x
			
			POST = 'POST'.freeze
			
			def initialize(app)
				super(app)
			end
			
			def needs_rewind?(request)
				content_type = request.headers['content-type']
				
				if request.method == POST and content_type.nil?
					return true
				end
				
				if BUFFERED_MEDIA_TYPES =~ content_type
					return true
				end
				
				return false
			end
			
			def call(request)
				if body = request.body and needs_rewind?(request)
					request.body = Async::HTTP::Body::Rewindable.new(body)
				end
				
				response = super
			end
		end
	end
end