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("luci.http.protocol")
  17 local ltn12 = require("luci.ltn12")
  18
  19
  20
  21 -- Server handler implementation
  22 Handler = luci.util.class()
  23
  24 -- Constructor
  25 function Handler.__init__(self)
  26         self.filters = {}
  27         self.handler = {}
  28 end
  29
  30
  31 -- Adds a filter to the filter chain
  32 function Handler.addfilter(self, filter)
  33         table.insert(self.filters, filter)
  34 end
  35
  36
  37 -- Creates a failure reply
  38 function Handler.failure(self, code, message)
  39         local response = Response(code, { ["Content-Type"] = "text/plain" })
  40         local sourceout = ltn12.source.string(message)
  41
  42         return response, sourceout
  43 end
  44
  45 -- Processes a request
  46 function Handler.process(self, request, sourcein, sinkerr, ...)
  47         local stat, response, sourceout
  48
  49         -- Process incoming filters
  50         for i, f in ipairs(self.filters) do
  51                 local i = f:get("input")
  52
  53                 if i then
  54                         sourcein = ltn12.source.chain(sourcein, i)
  55                 end
  56
  57                 if f.request then
  58                         f:request(request)
  59                 end
  60         end
  61
  62         -- Detect request Method
  63         local hname = "handle_" .. request.request_method
  64         if self[hname] then
  65                 -- Run the handler
  66                 stat, response, sourceout = luci.util.copcall(
  67                         self[hname], self, request, sourcein, sinkerr, ...
  68                 )
  69
  70                 -- Check for any errors
  71                 if not stat then
  72                         response, sourceout = self:failure(500, response)
  73                 end
  74         else
  75                 response, sourceout = self:failure(405, luci.http.protocol.statusmsg[405])
  76         end
  77
  78         -- Check data
  79         if not luci.util.instanceof(response, Response) then
  80                 response, sourceout = self:failure(500, "Core error: Invalid module response!")
  81         end
  82
  83         -- Process outgoing filters
  84         for i, f in ipairs(self.filters) do
  85                 local o = f:get("output")
  86
  87                 if o then
  88                         sourceout = ltn12.source.chain(sourceout, o)
  89                 end
  90
  91                 if f.response then
  92                         f:response(response)
  93                 end
  94         end
  95
  96         return response, sourceout
  97 end
  98
  99
 100
 101 -- Server Filter implementation
 102 Filter = luci.util.class()
 103
 104 function Filter.get(self, name)
 105         return self[name] and function(...) return self[name](self, ...) end
 106 end
 107
 108 -- Filters the incoming body stream
 109 -- abstract function Filter.input(chunk)
 110
 111 -- Filters the outgoing body stream
 112 -- abstract function Filter.output(chunk)
 113
 114 -- Filters the request object
 115 -- abstract function Filter.request(request)
 116
 117 -- Filters the response object
 118 -- abstract function Filter.response(response)
 119
 120
 121
 122 -- Handler Response
 123 Response = luci.util.class()
 124
 125 function Response.__init__(self, status, headers)
 126         self.status = tonumber(status) or 200
 127         self.headers = (type(headers) == "table") and headers or {}
 128 end
 129
 130 function Response.addheader(self, key, value)
 131         self.headers[key] = value
 132 end
 133
 134 function Response.setstatus(self, status)
 135         self.status = status
 136 end