libs/httpd/luasrc/httpd/server.lua

   1 --[[
   2
   3 HTTP server implementation for LuCI - helper class
   4 (c) 2008 Freifunk Leipzig / Jo-Philipp Wich <xm@leipzig.freifunk.net>
   5
   6 Licensed under the Apache License, Version 2.0 (the "License");
   7 you may not use this file except in compliance with the License.
   8 You may obtain a copy of the License at
   9
  10         http://www.apache.org/licenses/LICENSE-2.0
  11
  12 $Id$
  13
  14 ]]--
  15
  16 module("luci.httpd.server", package.seeall)
  17 require("luci.util")
  18
  19 READ_BUFSIZE = 1024
  20
  21
  22 VHost = luci.util.class()
  23
  24 function VHost.__init__(self, handler)
  25         self.handler = handler
  26         self.dhandler = {}
  27 end
  28
  29 function VHost.process(self, request, sourcein, sinkout, sinkerr)
  30         local handler = self.handler
  31
  32         local uri = request.env.REQUEST_URI:match("^([^?]*)")
  33
  34         -- SCRIPT_NAME
  35         request.env.SCRIPT_NAME = ""
  36
  37         -- Call URI part
  38         request.env.PATH_INFO = uri
  39
  40         for k, dhandler in pairs(self.dhandler) do
  41                 if k == uri or k.."/" == uri:sub(1, #k+1) then
  42                         handler = dhandler
  43                         request.env.SCRIPT_NAME = k
  44                         request.env.PATH_INFO   = uri:sub(#k+1)
  45                         break;
  46                 end
  47         end
  48
  49         if handler then
  50                 handler:process(request, sourcein, sinkout, sinkerr)
  51                 return true
  52         else
  53                 return false
  54         end
  55 end
  56
  57
  58 function VHost.set_default_handler(self, handler)
  59         self.handler = handler
  60 end
  61
  62
  63 function VHost.set_handler(self, match, handler)
  64         self.dhandler[match] = handler
  65 end
  66
  67
  68
  69 Server = luci.util.class()
  70
  71 function Server.__init__(self, host)
  72         self.clhandler = client_handler
  73         self.errhandler = error503
  74         self.host = host
  75         self.vhosts = {}
  76 end
  77
  78 function Server.set_default_vhost(self, vhost)
  79         self.host = vhost
  80 end
  81
  82 -- Sets a vhost
  83 function Server.set_vhost(self, name, vhost)
  84         self.vhosts[name] = vhost
  85 end
  86
  87 function Server.create_daemon_handlers(self)
  88         return function(...) return self:process(...) end,
  89                 function(...) return self:error503(...) end
  90 end
  91
  92 function Server.create_client_sources(self, client)
  93         -- Create LTN12 block source
  94         local block_source = function()
  95
  96                 -- Yielding here may cause chaos in coroutine based modules, be careful
  97                 -- coroutine.yield()
  98
  99                 local chunk, err, part = client:receive( READ_BUFSIZE )
 100
 101                 if chunk == nil and err == "timeout" then
 102                         return part
 103                 elseif chunk ~= nil then
 104                         return chunk
 105                 else
 106                         return nil, err
 107                 end
 108
 109         end
 110
 111
 112         -- Create LTN12 line source
 113         local line_source = ltn12.source.simplify( function()
 114
 115                 coroutine.yield()
 116
 117                 local chunk, err, part = client:receive("*l")
 118
 119                 -- Line too long
 120                 if chunk == nil and err ~= "timeout" then
 121
 122                         return nil, part
 123                                 and "Line exceeds maximum allowed length["..part.."]"
 124                                 or  "Unexpected EOF"
 125
 126                 -- Line ok
 127                 elseif chunk ~= nil then
 128
 129                         -- Strip trailing CR
 130                         chunk = chunk:gsub("\r$","")
 131
 132                         -- We got end of headers, switch to dummy source
 133                         if #chunk == 0 then
 134                                 return "", function()
 135                                         return nil
 136                                 end
 137                         else
 138                                 return chunk, nil
 139                         end
 140                 end
 141         end )
 142
 143         return block_source, line_source
 144 end
 145
 146
 147 function Server.error400(self, socket, msg)
 148         socket:send( "HTTP/1.0 400 Bad request\r\n" )
 149         socket:send( "Content-Type: text/plain\r\n\r\n" )
 150
 151         if msg then
 152                 socket:send( msg .. "\r\n" )
 153         end
 154
 155         socket:close()
 156 end
 157
 158 function Server.error500(self, socket, msg)
 159         socket:send( "HTTP/1.0 500 Internal Server Error\r\n" )
 160         socket:send( "Content-Type: text/plain\r\n\r\n" )
 161
 162         if msg then
 163                 socket:send( msg .. "\r\n" )
 164         end
 165
 166         socket:close()
 167 end
 168
 169 function Server.error503(self, socket)
 170         socket:send( "HTTP/1.0 503 Server unavailable\r\n" )
 171         socket:send( "Content-Type: text/plain\r\n\r\n" )
 172         socket:send( "There are too many clients connected, try again later\r\n" )
 173         socket:close()
 174 end
 175
 176
 177 function Server.process(self, client)
 178
 179         client:settimeout( 0 )
 180         local sourcein, sourcehdr = self:create_client_sources(client)
 181         local sinkerr = ltn12.sink.file(io.stderr)
 182
 183         -- FIXME: Add keep-alive support
 184         local sinkout = socket.sink("close-when-done", client)
 185
 186         coroutine.yield()
 187
 188         -- parse headers
 189         local message, err = luci.http.protocol.parse_message_header( sourcehdr )
 190
 191         if message then
 192                 -- If we have a HTTP/1.1 client and an Expect: 100-continue header then
 193                 -- respond with HTTP 100 Continue message
 194                 if message.http_version == 1.1 and message.headers['Expect'] and
 195                         message.headers['Expect'] == '100-continue'
 196                 then
 197                         client:send("HTTP/1.1 100 Continue\r\n\r\n")
 198                 end
 199
 200                 local host = self.vhosts[message.env.HTTP_HOST] or self.host
 201                 if host then
 202                         if host:process(message, sourcein, sinkout, sinkerr) then
 203                                 sinkout()
 204                         else
 205                                 self:error500( client, "No suitable path handler found" )
 206                         end
 207                 else
 208                         self:error500( client, "No suitable host handler found" )
 209                 end
 210         else
 211                 self:error400( client, err )
 212                 return nil
 213         end
 214 end