net/httpserver.lua

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