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 require("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 end
  28
  29
  30 -- Adds a filter to the filter chain
  31 function Handler.addfilter(self, filter)
  32         table.insert(self.filters, filter)
  33 end
  34
  35
  36 -- Creates a failure reply
  37 function Handler.failure(self, message)
  38         response = {
  39                 status = 500,
  40                 headers = {
  41                         ["Content-Type"] = "text/plain"
  42                 }
  43         }
  44
  45         sourceout = ltn12.source.string(message)
  46
  47         return response, sourceout
  48 end
  49
  50
  51 -- Processes a request
  52 function Handler.process(self, request, sourcein, sinkout, sinkerr)
  53         -- Process incoming filters
  54         for i, f in ipairs(self.filters) do
  55                 local i = f:get("input")
  56
  57                 if i then
  58                         sourcein = ltn12.source.chain(sourcein, i)
  59                 end
  60
  61                 if f.request then
  62                         f:request(request)
  63                 end
  64         end
  65
  66         -- Run the handler
  67         local stat, response, sourceout = luci.util.copcall(
  68                 self.handle, self, request, sourcein, sinkerr
  69         )
  70
  71         -- Check for any errors
  72         if not stat then
  73                 response, sourceout = self:failure(response)
  74         end
  75
  76         -- Check data
  77         if not luci.util.instanceof(response, Response) then
  78                 response, sourceout = self:failure("Core error: Invalid module response!")
  79         end
  80
  81         -- Process outgoing filters
  82         for i, f in ipairs(self.filters) do
  83                 local o = f:get("output")
  84
  85                 if o then
  86                         sourceout = ltn12.source.chain(sourceout, o)
  87                 end
  88
  89                 if f.response then
  90                         f:response(response)
  91                 end
  92         end
  93
  94         luci.http.protocol.push_response(request, response, sourceout, sinkout, sinkerr)
  95 end
  96
  97
  98
  99 -- Server Filter implementation
 100 Filter = luci.util.class()
 101
 102 function Filter.get(self, name)
 103         return self[name] and function(...) return self[name](self, ...) end
 104 end
 105
 106 -- Filters the incoming body stream
 107 -- abstract function Filter.input(chunk)
 108
 109 -- Filters the outgoing body stream
 110 -- abstract function Filter.output(chunk)
 111
 112 -- Filters the request object
 113 -- abstract function Filter.request(request)
 114
 115 -- Filters the response object
 116 -- abstract function Filter.response(response)
 117
 118
 119
 120 -- Handler Response
 121 Response = luci.util.class()
 122
 123 function Response.__init__(self, status, headers)
 124         self.status = tonumber(status) or 200
 125         self.headers = (type(headers) == "table") and headers or {}
 126 end
 127
 128 function Response.addheader(self, key, value)
 129         self.headers[key] = value
 130 end
 131
 132 function Response.setstatus(self, status)
 133         self.status = status
 134 end
 135
 136
 137 -- Status codes
 138 statusmsg = {
 139         [200] = "OK",
 140         [404] = "Not Found",
 141         [500] = "Internal Server Error",
 142 }