libs/httpd/luasrc/httpd/module.lua

   1 --[[
   2 LuCI - Lua Configuration Interface
   3
   4 Copyright 2008 Steven Barth <steven@midlink.org>
   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 module("luci.httpd.module", package.seeall)
  15 require("luci.util")
  16 require("ltn12")
  17
  18
  19
  20 -- Server handler implementation
  21 Handler = luci.util.class()
  22
  23 -- Constructor
  24 function Handler.__init__(self)
  25         self.filters = {}
  26 end
  27
  28
  29 -- Adds a filter to the filter chain
  30 function Handler.addfilter(self, filter)
  31         table.insert(self.filters, filter)
  32 end
  33
  34
  35 -- Creates a failure reply
  36 function Handler.failure(self, message)
  37         response = {
  38                 status = 500,
  39                 headers = {
  40                         ["Content-Type"] = "text/plain"
  41                 }
  42         }
  43
  44         sourceout = ltn12.source.string(message)
  45
  46         return response, sourceout
  47 end
  48
  49
  50 -- Processes a request
  51 function Handler.process(self, request, sourcein, sinkout, sinkerr)
  52         -- Process incoming filters
  53         for i, f in ipairs(self.filters) do
  54                 local i = f:get("input")
  55
  56                 if i then
  57                         sourcein = ltn12.source.chain(sourcein, i)
  58                 end
  59
  60                 if f.request then
  61                         f:request(request)
  62                 end
  63         end
  64
  65         -- Run the handler
  66         local stat, response, sourceout = luci.util.copcall(
  67                 self.handle, self, request, sourcein, sinkerr
  68         )
  69
  70         -- Check for any errors
  71         if not stat then
  72                 response, sourceout = self:failure(response)
  73         end
  74
  75         -- Check data
  76         if not luci.util.instanceof(response, Response) then
  77                 response, sourceout = self:failure("Core error: Invalid module response!")
  78         end
  79
  80         -- Process outgoing filters
  81         for i, f in ipairs(self.filters) do
  82                 local o = f:get("output")
  83
  84                 if o then
  85                         sourceout = ltn12.source.chain(sourceout, o)
  86                 end
  87
  88                 if f.response then
  89                         f:response(response)
  90                 end
  91         end
  92
  93
  94         -- Print status and headers
  95         sinkout("HTTP/1.1 " .. response.status .. " " .. statusmsg[response.status] .. "\r\n")
  96         for k, v in pairs(response.headers) do
  97                 sinkout(k .. ": " .. v .. "\r\n")
  98         end
  99
 100         -- End of Headers
 101         sinkout("\r\n")
 102
 103         -- Pump content
 104         if sourceout then
 105                 ltn12.pump.all(sourceout, sinkout)
 106         end
 107 end
 108
 109
 110
 111 -- Server Filter implementation
 112 Filter = luci.util.class()
 113
 114 function Filter.get(self, name)
 115         return self[name] and function(...) return self[name](self, ...) end
 116 end
 117
 118 -- Filters the incoming body stream
 119 -- abstract function Filter.input(chunk)
 120
 121 -- Filters the outgoing body stream
 122 -- abstract function Filter.output(chunk)
 123
 124 -- Filters the request object
 125 -- abstract function Filter.request(request)
 126
 127 -- Filters the response object
 128 -- abstract function Filter.response(response)
 129
 130
 131
 132 -- Handler Response
 133 Response = luci.util.class()
 134
 135 function Response.__init__(self, status, headers)
 136         self.status = tonumber(status) or 200
 137         self.headers = (type(headers) == "table") and headers or {}
 138 end
 139
 140 function Response.addheader(self, key, value)
 141         self.headers[key] = value
 142 end
 143
 144 function Response.setstatus(self, status)
 145         self.status = status
 146 end
 147
 148
 149 -- Status codes
 150 statusmsg = {
 151         [200] = "OK",
 152         [404] = "Not Found",
 153         [500] = "Internal Server Error",
 154 }