net/httpserver.lua

   1 -- Prosody IM
   2 -- Copyright (C) 2008-2009 Matthew Wild
   3 -- Copyright (C) 2008-2009 Waqas Hussain
   4 --
   5 -- This project is MIT/X11 licensed. Please see the
   6 -- COPYING file in the source package for more information.
   7 --
   8
   9
  10 local socket = require "socket"
  11 local server = require "net.server"
  12 local url_parse = require "socket.url".parse;
  13
  14 local connlisteners_start = require "net.connlisteners".start;
  15 local connlisteners_get = require "net.connlisteners".get;
  16 local listener;
  17
  18 local t_insert, t_concat = table.insert, table.concat;
  19 local s_match, s_gmatch = string.match, string.gmatch;
  20 local tonumber, tostring, pairs = tonumber, tostring, pairs;
  21
  22 local urlencode = function (s) return s and (s:gsub("%W", function (c) return string.format("%%%02x", c:byte()); end)); end
  23
  24 local log = require "util.logger".init("httpserver");
  25
  26 local http_servers = {};
  27
  28 module "httpserver"
  29
  30 local default_handler;
  31
  32 local function expectbody(reqt)
  33     return reqt.method == "POST";
  34 end
  35
  36 local function send_response(request, response)
  37         -- Write status line
  38         local resp;
  39         if response.body then
  40                 log("debug", "Sending response to %s", request.id);
  41                 resp = { "HTTP/1.0 ", response.status or "200 OK", "\r\n"};
  42                 local h = response.headers;
  43                 if h then
  44                         for k, v in pairs(h) do
  45                                 t_insert(resp, k);
  46                                 t_insert(resp, ": ");
  47                                 t_insert(resp, v);
  48                                 t_insert(resp, "\r\n");
  49                         end
  50                 end
  51                 if response.body and not (h and h["Content-Length"]) then
  52                         t_insert(resp, "Content-Length: ");
  53                         t_insert(resp, #response.body);
  54                         t_insert(resp, "\r\n");
  55                 end
  56                 t_insert(resp, "\r\n");
  57
  58                 if response.body and request.method ~= "HEAD" then
  59                         t_insert(resp, response.body);
  60                 end
  61         else
  62                 -- Response we have is just a string (the body)
  63                 log("debug", "Sending response to %s: %s", request.id or "<none>", response or "<none>");
  64
  65                 resp = { "HTTP/1.0 200 OK\r\n" };
  66                 t_insert(resp, "Connection: close\r\n");
  67                 t_insert(resp, "Content-Length: ");
  68                 t_insert(resp, #response);
  69                 t_insert(resp, "\r\n\r\n");
  70
  71                 t_insert(resp, response);
  72         end
  73         request.write(t_concat(resp));
  74         if not request.stayopen then
  75                 request:destroy();
  76         end
  77 end
  78
  79 local function call_callback(request, err)
  80         if request.handled then return; end
  81         request.handled = true;
  82         local callback = request.callback;
  83         if not callback and request.path then
  84                 local path = request.url.path;
  85                 local base = path:match("^/([^/?]+)");
  86                 if not base then
  87                         base = path:match("^http://[^/?]+/([^/?]+)");
  88                 end
  89
  90                 callback = (request.server and request.server.handlers[base]) or default_handler;
  91                 if callback == default_handler then
  92                         log("debug", "Default callback for this request (base: "..tostring(base)..")")
  93                 end
  94         end
  95         if callback then
  96                 if err then
  97                         log("debug", "Request error: "..err);
  98                         if not callback(nil, err, request) then
  99                                 destroy_request(request);
 100                         end
 101                         return;
 102                 end
 103
 104                 local response = callback(request.method, request.body and t_concat(request.body), request);
 105                 if response then
 106                         if response == true and not request.destroyed then
 107                                 -- Keep connection open, we will reply later
 108                                 log("warn", "Request %s left open, on_destroy is %s", request.id, tostring(request.on_destroy));
 109                         elseif response ~= true then
 110                                 -- Assume response
 111                                 send_response(request, response);
 112                                 destroy_request(request);
 113                         end
 114                 else
 115                         log("debug", "Request handler provided no response, destroying request...");
 116                         -- No response, close connection
 117                         destroy_request(request);
 118                 end
 119         end
 120 end
 121
 122 local function request_reader(request, data, startpos)
 123         if not data then
 124                 if request.body then
 125                         call_callback(request);
 126                 else
 127                         -- Error.. connection was closed prematurely
 128                         call_callback(request, "connection-closed");
 129                 end
 130                 -- Here we force a destroy... the connection is gone, so we can't reply later
 131                 destroy_request(request);
 132                 return;
 133         end
 134         if request.state == "body" then
 135                 log("debug", "Reading body...")
 136                 if not request.body then request.body = {}; request.havebodylength, request.bodylength = 0, tonumber(request.headers["content-length"]); end
 137                 if startpos then
 138                         data = data:sub(startpos, -1)
 139                 end
 140                 t_insert(request.body, data);
 141                 if request.bodylength then
 142                         request.havebodylength = request.havebodylength + #data;
 143                         if request.havebodylength >= request.bodylength then
 144                                 -- We have the body
 145                                 call_callback(request);
 146                         end
 147                 end
 148         elseif request.state == "headers" then
 149                 log("debug", "Reading headers...")
 150                 local pos = startpos;
 151                 local headers = request.headers or {};
 152                 for line in data:gmatch("(.-)\r\n") do
 153                         startpos = (startpos or 1) + #line + 2;
 154                         local k, v = line:match("(%S+): (.+)");
 155                         if k and v then
 156                                 headers[k:lower()] = v;
 157 --                              log("debug", "Header: "..k:lower().." = "..v);
 158                         elseif #line == 0 then
 159                                 request.headers = headers;
 160                                 break;
 161                         else
 162                                 log("debug", "Unhandled header line: "..line);
 163                         end
 164                 end
 165
 166                 if not expectbody(request) then
 167                         call_callback(request);
 168                         return;
 169                 end
 170
 171                 -- Reached the end of the headers
 172                 request.state = "body";
 173                 if #data > startpos then
 174                         return request_reader(request, data:sub(startpos, -1));
 175                 end
 176         elseif request.state == "request" then
 177                 log("debug", "Reading request line...")
 178                 local method, path, http, linelen = data:match("^(%S+) (%S+) HTTP/(%S+)\r\n()", startpos);
 179                 if not method then
 180                         return call_callback(request, "invalid-status-line");
 181                 end
 182
 183                 request.method, request.path, request.httpversion = method, path, http;
 184
 185                 request.url = url_parse(request.path);
 186
 187                 log("debug", method.." request for "..tostring(request.path) .. " on port "..request.handler.serverport());
 188
 189                 if request.onlystatus then
 190                         if not call_callback(request) then
 191                                 return;
 192                         end
 193                 end
 194
 195                 request.state = "headers";
 196
 197                 if #data > linelen then
 198                         return request_reader(request, data:sub(linelen, -1));
 199                 end
 200         end
 201 end
 202
 203 -- The default handler for requests
 204 default_handler = function (method, body, request)
 205         log("debug", method.." request for "..tostring(request.path) .. " on port "..request.handler.serverport());
 206         return { status = "404 Not Found",
 207                         headers = { ["Content-Type"] = "text/html" },
 208                         body = "<html><head><title>Page Not Found</title></head><body>Not here :(</body></html>" };
 209 end
 210
 211
 212 function new_request(handler)
 213         return { handler = handler, conn = handler.socket,
 214                         write = handler.write, state = "request",
 215                         server = http_servers[handler.serverport()],
 216                         send = send_response,
 217                         destroy = destroy_request,
 218                         id = tostring{}:match("%x+$")
 219                          };
 220 end
 221
 222 function destroy_request(request)
 223         log("debug", "Destroying request %s", request.id);
 224         listener = listener or connlisteners_get("httpserver");
 225         if not request.destroyed then
 226                 request.destroyed = true;
 227                 if request.on_destroy then
 228                         log("debug", "Request has destroy callback");
 229                         request.on_destroy(request);
 230                 else
 231                         log("debug", "Request has no destroy callback");
 232                 end
 233                 request.handler.close()
 234                 if request.conn then
 235                         listener.disconnect(request.conn, "closed");
 236                 end
 237         end
 238 end
 239
 240 function new(params)
 241         local http_server = http_servers[params.port];
 242         if not http_server then
 243                 http_server = { handlers = {} };
 244                 http_servers[params.port] = http_server;
 245                 -- We weren't already listening on this port, so start now
 246                 connlisteners_start("httpserver", params);
 247         end
 248         if params.base then
 249                 http_server.handlers[params.base] = params.handler;
 250         end
 251 end
 252
 253 _M.request_reader = request_reader;
 254 _M.send_response = send_response;
 255 _M.urlencode = urlencode;
 256
 257 return _M;