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         luci.http.push_response(request, status, response, sourceout, sinkout, sinkerr)
  94 end
  95
  96
  97
  98 -- Server Filter implementation
  99 Filter = luci.util.class()
 100
 101 function Filter.get(self, name)
 102         return self[name] and function(...) return self[name](self, ...) end
 103 end
 104
 105 -- Filters the incoming body stream
 106 -- abstract function Filter.input(chunk)
 107
 108 -- Filters the outgoing body stream
 109 -- abstract function Filter.output(chunk)
 110
 111 -- Filters the request object
 112 -- abstract function Filter.request(request)
 113
 114 -- Filters the response object
 115 -- abstract function Filter.response(response)
 116
 117
 118
 119 -- Handler Response
 120 Response = luci.util.class()
 121
 122 function Response.__init__(self, status, headers)
 123         self.status = tonumber(status) or 200
 124         self.headers = (type(headers) == "table") and headers or {}
 125 end
 126
 127 function Response.addheader(self, key, value)
 128         self.headers[key] = value
 129 end
 130
 131 function Response.setstatus(self, status)
 132         self.status = status
 133 end
 134
 135
 136 -- Status codes
 137 statusmsg = {
 138         [200] = "OK",
 139         [404] = "Not Found",
 140         [500] = "Internal Server Error",
 141 }