libs/httpd/luasrc/httpd/handler/luci.lua

   1 --[[
   2
   3 HTTP server implementation for LuCI - luci handler
   4 (c) 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 ]]--
  15
  16 module("luci.httpd.handler.luci", package.seeall)
  17
  18 require("luci.dispatcher")
  19 require("luci.http")
  20 require("luci.http.protocol.date")
  21 local ltn12 = require("luci.ltn12")
  22
  23 Luci = luci.util.class(luci.httpd.module.Handler)
  24 Response = luci.httpd.module.Response
  25
  26 function Luci.__init__(self, limit)
  27         luci.httpd.module.Handler.__init__(self)
  28         self.limit = limit or 5
  29         self.running = {}
  30         setmetatable(self.running, {__mode = "k"})
  31 end
  32
  33 function Luci.handle_head(self, ...)
  34         local response, sourceout = self:handle_get(...)
  35         return response
  36 end
  37
  38 function Luci.handle_post(self, ...)
  39         return self:handle_get(...)
  40 end
  41
  42 function Luci.handle_get(self, request, sourcein, sinkerr)
  43         local reaped  = false
  44         local running = 0
  45
  46         for _, v in pairs(self.running) do
  47                 if v then running = running + 1 end
  48         end
  49
  50         if self.limit and running >= self.limit then
  51                 for k, v in ipairs(self.running) do
  52                         if coroutine.status(k) == "dead" then
  53                                 self.running[k] = nil
  54                                 running = running - 1
  55                                 reaped  = true
  56                         end
  57                 end
  58
  59                 if reaped then collectgarbage() end
  60
  61                 if running >= self.limit then
  62                         return self:failure(503, "Overload %i/%i" % { running, self.limit } )
  63                 end
  64         end
  65
  66         self.running[coroutine.running()] = true
  67
  68         local r = luci.http.Request(
  69                 request.env,
  70                 sourcein,
  71                 sinkerr
  72         )
  73
  74         local res, id, data1, data2 = true, 0, nil, nil
  75         local headers = {}
  76         local status = 200
  77         local active = true
  78
  79         local x = coroutine.create(luci.dispatcher.httpdispatch)
  80         while not id or id < 3 do
  81                 coroutine.yield()
  82
  83                 res, id, data1, data2 = coroutine.resume(x, r)
  84
  85                 if not res then
  86                         status = 500
  87                         headers["Content-Type"] = "text/plain"
  88                         local err = {id}
  89                         return Response( status, headers ), function() return table.remove(err) end
  90                 end
  91
  92                 if id == 1 then
  93                         status = data1
  94                 elseif id == 2 then
  95                         headers[data1] = data2
  96                 end
  97         end
  98
  99         local function iter()
 100                 local res, id, data = coroutine.resume(x)
 101                 if not res then
 102                         return nil, id
 103                 elseif not id or not active then
 104                         return true
 105                 elseif id == 5 then
 106                         active = false
 107
 108                         while (coroutine.resume(x)) do
 109                         end
 110
 111                         return nil
 112                 elseif id == 4 then
 113                         return data
 114                 end
 115                 if coroutine.status(x) == "dead" then
 116                         return nil
 117                 end
 118         end
 119
 120         return Response(status, headers), iter
 121 end