lib/nitcorn/proxy.nit

   1 # This file is part of NIT ( http://www.nitlanguage.org ).
   2 #
   3 # Copyright 2015 Philippe Pépos Petitclerc <ppeposp@gmail.com>
   4 #
   5 # Licensed under the Apache License, Version 2.0 (the "License");
   6 # you may not use this file except in compliance with the License.
   7 # You may obtain a copy of the License at
   8 #
   9 #     http://www.apache.org/licenses/LICENSE-2.0
  10 #
  11 # Unless required by applicable law or agreed to in writing, software
  12 # distributed under the License is distributed on an "AS IS" BASIS,
  13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14 # See the License for the specific language governing permissions and
  15 # limitations under the License.
  16
  17 # Provides the `ProxyAction` action, which redirects requests to another interface
  18 module proxy
  19
  20 import curl
  21 import reactor
  22
  23 # A request proxy. All requests received by this action will be redirected to
  24 # its target. All headers are forwarded including User-Agent.
  25 #
  26 # Please note: Requests passed to this action are blocking.
  27 class ProxyAction
  28         super Action
  29
  30         # Target interface where to dispatch proxied requests
  31         var target: Interface
  32
  33         redef fun answer(http_request, turi) do
  34
  35                 var request = new CurlHTTPRequest("http://{self.target}{turi}")
  36
  37                 var curl_headers = new HeaderMap
  38
  39                 for k, v in http_request.header do
  40                         if k == "User-Agent" then
  41                                 request.user_agent = v
  42                         else
  43                                 curl_headers[k] = v
  44                         end
  45                 end
  46
  47                 var curl_response = request.execute
  48                 var response: HttpResponse
  49
  50                 if curl_response isa CurlResponseSuccess then
  51                         response = new HttpResponse(curl_response.status_code)
  52                         response.body = curl_response.body_str
  53                 else if curl_response isa CurlResponseFailed then
  54                         response = new HttpResponse(500)
  55
  56                         # CURLE_COULDNT_RESOLVE_HOST
  57                         if curl_response.error_code == 6 then
  58                                 response.status_code = 502 # Bad Gateway
  59                         # CURLE_URL_MALFORMAT
  60                         else if curl_response.error_code == 3 then
  61                                 response.status_code = 520 # Unknown Error
  62                         # CURLE_COULDNT_CONNECT
  63                         else if curl_response.error_code == 7 then
  64                                 response.status_code = 502 # Bad Gateway
  65                         end
  66                 else abort
  67
  68                 return response
  69
  70         end
  71 end