lib/nitcorn/http_response.nit

   1 # This file is part of NIT ( http://www.nitlanguage.org ).
   2 #
   3 # Copyright 2013 Frederic Sevillano
   4 # Copyright 2013 Jean-Philippe Caissy <jpcaissy@piji.ca>
   5 # Copyright 2014 Alexis Laferrière <alexis.laf@xymus.net>
   6 #
   7 # Licensed under the Apache License, Version 2.0 (the "License");
   8 # you may not use this file except in compliance with the License.
   9 # You may obtain a copy of the License at
  10 #
  11 #     http://www.apache.org/licenses/LICENSE-2.0
  12 #
  13 # Unless required by applicable law or agreed to in writing, software
  14 # distributed under the License is distributed on an "AS IS" BASIS,
  15 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  16 # See the License for the specific language governing permissions and
  17 # limitations under the License.
  18
  19 # Provides the `HttpResponse` class and `http_status_codes`
  20 module http_response
  21
  22 import serialization
  23 private import template
  24
  25 # A response to send over HTTP
  26 class HttpResponse
  27         serialize
  28
  29         # HTTP protocol version
  30         var http_version = "HTTP/1.0" is writable
  31
  32         # Status code of this response (200, 404, etc.)
  33         var status_code: Int is writable
  34
  35         # Return the message associated to `status_code`
  36         fun status_message: nullable String do return http_status_codes[status_code]
  37
  38         # Headers of this response as a `Map`
  39         var header = new HashMap[String, String]
  40
  41         # Body of this response
  42         var body: Writable = "" is writable
  43
  44         # Files appended after `body`
  45         var files = new Array[String]
  46
  47         # Finalize this response before sending it over HTTP
  48         fun finalize
  49         do
  50                 # Set the content length if not already set
  51                 if not header.keys.has("Content-Length") then
  52                         # Size of the body
  53                         var len
  54                         var body = self.body
  55                         if body isa Text then
  56                                 len = body.byte_length
  57                         else if body isa Bytes then
  58                                 len = body.length
  59                         else
  60                                 # We need the length, but there is no length in a writable.
  61                                 # So just render it as a bytes then measure :/
  62                                 body = body.write_to_bytes
  63                                 len = body.length
  64                                 # Keep the body as bytes since we have it
  65                                 self.body = body
  66                         end
  67
  68                         # Size of included files
  69                         for path in files do
  70                                 # TODO handle these error cases elsewhere, an error here will result in an invalid response
  71                                 if not path.file_exists then
  72                                         print_error "File does not exists at '{path}'"
  73                                         continue
  74                                 end
  75
  76                                 var stat = path.file_stat
  77                                 if stat == null then
  78                                         print_error "Failed to stat file at '{path}'"
  79                                         continue
  80                                 end
  81
  82                                 len += stat.size
  83                         end
  84
  85                         # Set header
  86                         header["Content-Length"] = len.to_s
  87                 end
  88
  89                 # Set server ID
  90                 if not header.keys.has("Server") then header["Server"] = "nitcorn"
  91         end
  92
  93         # Get this reponse as a string according to HTTP protocol
  94         fun render: Writable
  95         do
  96                 finalize
  97
  98                 var buf = new Template
  99                 buf.add("{http_version} {status_code} {status_message or else ""}\r\n")
 100                 for key, value in header do
 101                         buf.add("{key}: {value}\r\n")
 102                 end
 103                 buf.add("\r\n")
 104                 buf.add body
 105                 return buf
 106         end
 107 end
 108
 109 # Helper class to associate HTTP status code to their message
 110 #
 111 # You probably want the default instance available as the top-level method
 112 # `http_status_codes`.
 113 class HttpStatusCodes
 114
 115         # All know code and their message
 116         var codes = new HashMap[Int, String]
 117
 118         # Init the status `codes` list.
 119         protected init is old_style_init do insert_status_codes
 120
 121         # Get the message associated to the status `code`, return `null` in unknown
 122         fun [](code: Int): nullable String
 123         do
 124                 if codes.keys.has(code) then
 125                         return codes[code]
 126                 else return null
 127         end
 128
 129         private fun insert_status_codes
 130         do
 131                 codes[100] = "Continue"
 132                 codes[101] = "Switching Protocols"
 133                 codes[200] = "OK"
 134                 codes[201] = "Created"
 135                 codes[202] = "Accepted"
 136                 codes[203] = "Non-Authoritative Information"
 137                 codes[204] = "No Content"
 138                 codes[205] = "Reset Content"
 139                 codes[206] = "Partial Content"
 140                 codes[300] = "Multiple Choices"
 141                 codes[301] = "Moved Permanently"
 142                 codes[302] = "Found"
 143                 codes[303] = "See Other"
 144                 codes[304] = "Not Modified"
 145                 codes[305] = "Use Proxy"
 146                 codes[307] = "Temporary Redirect"
 147                 codes[400] = "Bad Request"
 148                 codes[401] = "Unauthorized"
 149                 codes[402] = "Payment Requred"
 150                 codes[403] = "Forbidden"
 151                 codes[404] = "Not Found"
 152                 codes[405] = "Method Not Allowed"
 153                 codes[406] = "Not Acceptable"
 154                 codes[407] = "Proxy Authentication Required"
 155                 codes[408] = "Request Timeout"
 156                 codes[409] = "Conflict"
 157                 codes[410] = "Gone"
 158                 codes[411] = "Length Required"
 159                 codes[412] = "Precondition Failed"
 160                 codes[413] = "Request Entity Too Large"
 161                 codes[414] = "Request-URI Too Long"
 162                 codes[415] = "Unsupported Media Type"
 163                 codes[416] = "Requested Range Not Satisfiable"
 164                 codes[417] = "Expectation Failed"
 165                 codes[500] = "Internal Server Error"
 166                 codes[501] = "Not Implemented"
 167                 codes[502] = "Bad Gateway"
 168                 codes[503] = "Service Unavailable"
 169                 codes[504] = "Gateway Timeout"
 170                 codes[505] = "HTTP Version Not Supported"
 171         end
 172 end
 173
 174 # Get the default instance of `HttpStatusCodes`
 175 fun http_status_codes: HttpStatusCodes do return once new HttpStatusCodes