net/http/parser.lua

   1
   2 local tonumber = tonumber;
   3 local assert = assert;
   4 local url_parse = require "socket.url".parse;
   5 local urldecode = require "net.http".urldecode;
   6
   7 local function preprocess_path(path)
   8         path = urldecode((path:gsub("//+", "/")));
   9         if path:sub(1,1) ~= "/" then
  10                 path = "/"..path;
  11         end
  12         local level = 0;
  13         for component in path:gmatch("([^/]+)/") do
  14                 if component == ".." then
  15                         level = level - 1;
  16                 elseif component ~= "." then
  17                         level = level + 1;
  18                 end
  19                 if level < 0 then
  20                         return nil;
  21                 end
  22         end
  23         return path;
  24 end
  25
  26 local httpstream = {};
  27
  28 function httpstream.new(success_cb, error_cb, parser_type, options_cb)
  29         local client = true;
  30         if not parser_type or parser_type == "server" then client = false; else assert(parser_type == "client", "Invalid parser type"); end
  31         local buf = "";
  32         local chunked;
  33         local state = nil;
  34         local packet;
  35         local len;
  36         local have_body;
  37         local error;
  38         return {
  39                 feed = function(self, data)
  40                         if error then return nil, "parse has failed"; end
  41                         if not data then -- EOF
  42                                 if state and client and not len then -- reading client body until EOF
  43                                         packet.body = buf;
  44                                         success_cb(packet);
  45                                 elseif buf ~= "" then -- unexpected EOF
  46                                         error = true; return error_cb();
  47                                 end
  48                                 return;
  49                         end
  50                         buf = buf..data;
  51                         while #buf > 0 do
  52                                 if state == nil then -- read request
  53                                         local index = buf:find("\r\n\r\n", nil, true);
  54                                         if not index then return; end -- not enough data
  55                                         local method, path, httpversion, status_code, reason_phrase;
  56                                         local first_line;
  57                                         local headers = {};
  58                                         for line in buf:sub(1,index+1):gmatch("([^\r\n]+)\r\n") do -- parse request
  59                                                 if first_line then
  60                                                         local key, val = line:match("^([^%s:]+): *(.*)$");
  61                                                         if not key then error = true; return error_cb("invalid-header-line"); end -- TODO handle multi-line and invalid headers
  62                                                         key = key:lower();
  63                                                         headers[key] = headers[key] and headers[key]..","..val or val;
  64                                                 else
  65                                                         first_line = line;
  66                                                         if client then
  67                                                                 httpversion, status_code, reason_phrase = line:match("^HTTP/(1%.[01]) (%d%d%d) (.*)$");
  68                                                                 if not status_code then error = true; return error_cb("invalid-status-line"); end
  69                                                                 have_body = not
  70                                                                          ( (options_cb and options_cb().method == "HEAD")
  71                                                                         or (status_code == 204 or status_code == 304 or status_code == 301)
  72                                                                         or (status_code >= 100 and status_code < 200) );
  73                                                                 chunked = have_body and headers["transfer-encoding"] == "chunked";
  74                                                         else
  75                                                                 method, path, httpversion = line:match("^(%w+) (%S+) HTTP/(1%.[01])$");
  76                                                                 if not method then error = true; return error_cb("invalid-status-line"); end
  77                                                         end
  78                                                 end
  79                                         end
  80                                         if not first_line then error = true; return error_cb("invalid-status-line"); end
  81                                         len = tonumber(headers["content-length"]); -- TODO check for invalid len
  82                                         if client then
  83                                                 -- FIXME handle '100 Continue' response (by skipping it)
  84                                                 if not have_body then len = 0; end
  85                                                 packet = {
  86                                                         code = status_code;
  87                                                         httpversion = httpversion;
  88                                                         headers = headers;
  89                                                         body = have_body and "" or nil;
  90                                                         -- COMPAT the properties below are deprecated
  91                                                         responseversion = httpversion;
  92                                                         responseheaders = headers;
  93                                                 };
  94                                         else
  95                                                 local parsed_url;
  96                                                 if path:byte() == 47 then -- starts with /
  97                                                         local _path, _query = path:match("([^?]*).?(.*)");
  98                                                         if _query == "" then _query = nil; end
  99                                                         parsed_url = { path = _path, query = _query };
 100                                                 else
 101                                                         parsed_url = url_parse(path);
 102                                                 end
 103                                                 path = preprocess_path(parsed_url.path);
 104                                                 headers.host = parsed_url.host or headers.host;
 105
 106                                                 len = len or 0;
 107                                                 packet = {
 108                                                         method = method;
 109                                                         url = parsed_url;
 110                                                         path = path;
 111                                                         httpversion = httpversion;
 112                                                         headers = headers;
 113                                                         body = nil;
 114                                                 };
 115                                         end
 116                                         buf = buf:sub(index + 4);
 117                                         state = true;
 118                                 end
 119                                 if state then -- read body
 120                                         if client then
 121                                                 if chunked then
 122                                                         local index = buf:find("\r\n", nil, true);
 123                                                         if not index then return; end -- not enough data
 124                                                         local chunk_size = buf:match("^%x+");
 125                                                         if not chunk_size then error = true; return error_cb("invalid-chunk-size"); end
 126                                                         chunk_size = tonumber(chunk_size, 16);
 127                                                         index = index + 2;
 128                                                         if chunk_size == 0 then
 129                                                                 state = nil; success_cb(packet);
 130                                                         elseif #buf - index + 1 >= chunk_size then -- we have a chunk
 131                                                                 packet.body = packet.body..buf:sub(index, index + chunk_size - 1);
 132                                                                 buf = buf:sub(index + chunk_size);
 133                                                         end
 134                                                         error("trailers"); -- FIXME MUST read trailers
 135                                                 elseif len and #buf >= len then
 136                                                         packet.body, buf = buf:sub(1, len), buf:sub(len + 1);
 137                                                         state = nil; success_cb(packet);
 138                                                 end
 139                                         elseif #buf >= len then
 140                                                 packet.body, buf = buf:sub(1, len), buf:sub(len + 1);
 141                                                 state = nil; success_cb(packet);
 142                                         else
 143                                                 break;
 144                                         end
 145                                 end
 146                         end
 147                 end;
 148         };
 149 end
 150
 151 return httpstream;