# frozen_string_literal: true
# Copyright, 2017, 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
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.
require 'rack'
require_relative 'input'
require_relative 'response'
require_relative 'early_hints'
require 'async/logger'
module Falcon
module Adapters
class Rack
# CGI keys (https://tools.ietf.org/html/rfc3875#section-4.1)
HTTP_HOST = 'HTTP_HOST'.freeze
PATH_INFO = 'PATH_INFO'.freeze
REQUEST_METHOD = 'REQUEST_METHOD'.freeze
REQUEST_PATH = 'REQUEST_PATH'.freeze
REQUEST_URI = 'REQUEST_URI'.freeze
SCRIPT_NAME = 'SCRIPT_NAME'.freeze
QUERY_STRING = 'QUERY_STRING'.freeze
SERVER_PROTOCOL = 'SERVER_PROTOCOL'.freeze
SERVER_NAME = 'SERVER_NAME'.freeze
SERVER_PORT = 'SERVER_PORT'.freeze
REMOTE_ADDR = 'REMOTE_ADDR'.freeze
CONTENT_TYPE = 'CONTENT_TYPE'.freeze
CONTENT_LENGTH = 'CONTENT_LENGTH'.freeze
# Rack environment variables
RACK_VERSION = 'rack.version'.freeze
RACK_ERRORS = 'rack.errors'.freeze
RACK_LOGGER = 'rack.logger'.freeze
RACK_INPUT = 'rack.input'.freeze
RACK_MULTITHREAD = 'rack.multithread'.freeze
RACK_MULTIPROCESS = 'rack.multiprocess'.freeze
RACK_RUNONCE = 'rack.run_once'.freeze
RACK_URL_SCHEME = 'rack.url_scheme'.freeze
RACK_HIJACK = 'rack.hijack'.freeze
RACK_IS_HIJACK = 'rack.hijack?'.freeze
RACK_HIJACK_IO = 'rack.hijack_io'.freeze
RACK_EARLY_HINTS = "rack.early_hints".freeze
ASYNC_HTTP_REQUEST = "async.http.request".freeze
# Header constants
HTTP_X_FORWARDED_PROTO = 'HTTP_X_FORWARDED_PROTO'.freeze
def initialize(app, logger = Async.logger)
@app = app
raise ArgumentError, "App must be callable!" unless @app.respond_to?(:call)
@logger = logger
end
# Rack separates multiple headers with the same key, into a single field with multiple "lines".
def unwrap_headers(headers, env)
headers.each do |key, value|
http_key = "HTTP_#{key.upcase.tr('-', '_')}"
if current_value = env[http_key]
env[http_key] = "#{current_value};#{value}"
else
env[http_key] = value
end
end
end
# Process the incoming request into a valid rack env.
def unwrap_request(request, env)
if content_type = request.headers.delete('content-type')
env[CONTENT_TYPE] = content_type
end
# In some situations we don't know the content length, e.g. when using chunked encoding, or when decompressing the body.
if body = request.body and length = body.length
env[CONTENT_LENGTH] = length.to_s
end
self.unwrap_headers(request.headers, env)
# HTTP/2 prefers `:authority` over `host`, so we do this for backwards compatibility.
env[HTTP_HOST] ||= request.authority
# This is the HTTP/1 header for the scheme of the request and is used by Rack.
# Technically it should use the Forwarded header but this is not common yet.
# https://tools.ietf.org/html/rfc7239#section-5.4
# https://github.com/rack/rack/issues/1310
env[HTTP_X_FORWARDED_PROTO] ||= request.scheme
if remote_address = request.remote_address
env[REMOTE_ADDR] = remote_address.ip_address if remote_address.ip?
end
end
def call(request)
request_path, query_string = request.path.split('?', 2)
server_name, server_port = (request.authority || '').split(':', 2)
env = {
RACK_VERSION => [2, 0, 0],
ASYNC_HTTP_REQUEST => request,
RACK_INPUT => Input.new(request.body),
RACK_ERRORS => $stderr,
RACK_LOGGER => Async.logger,
RACK_MULTITHREAD => true,
RACK_MULTIPROCESS => true,
RACK_RUNONCE => false,
# The HTTP request method, such as “GET” or “POST”. This cannot ever be an empty string, and so is always required.
REQUEST_METHOD => request.method,
# The initial portion of the request URL's “path” that corresponds to the application object, so that the application knows its virtual “location”. This may be an empty string, if the application corresponds to the “root” of the server.
SCRIPT_NAME => '',
# The remainder of the request URL's “path”, designating the virtual “location” of the request's target within the application. This may be an empty string, if the request URL targets the application root and does not have a trailing slash. This value may be percent-encoded when originating from a URL.
PATH_INFO => request_path,
REQUEST_PATH => request_path,
REQUEST_URI => request.path,
# The portion of the request URL that follows the ?, if any. May be empty, but is always required!
QUERY_STRING => query_string || '',
# The server protocol (e.g. HTTP/1.1):
SERVER_PROTOCOL => request.version,
# The request scheme:
RACK_URL_SCHEME => request.scheme,
# I'm not sure what sane defaults should be here:
SERVER_NAME => server_name || '',
SERVER_PORT => server_port || '',
# We support both request and response hijack.
RACK_IS_HIJACK => true,
}
self.unwrap_request(request, env)
if request.push?
env[RACK_EARLY_HINTS] = EarlyHints.new(request)
end
full_hijack = false
if request.hijack?
env[RACK_HIJACK] = lambda do
wrapper = request.hijack!
full_hijack = true
# We dup this as it might be taken out of the normal control flow, and the io will be closed shortly after returning from this method.
io = wrapper.io.dup
wrapper.close
# This is implicitly returned:
env[RACK_HIJACK_IO] = io
end
end
status, headers, body = @app.call(env)
# If there was a full hijack:
if full_hijack
return nil
else
return Response.wrap(status, headers, body, request)
end
rescue => exception
@logger.error(self) {exception}
return failure_response(exception)
end
def failure_response(exception)
Protocol::HTTP::Response.for_exception(exception)
end
end
end
end