share/media/cbsnews.lua

   1 -- libquvi-scripts
   2 -- Copyright (C) 2010-2013  Toni Gundogdu <legatvs@gmail.com>
   3 --
   4 -- This file is part of libquvi-scripts <http://quvi.sourceforge.net/>.
   5 --
   6 -- This program is free software: you can redistribute it and/or
   7 -- modify it under the terms of the GNU Affero General Public
   8 -- License as published by the Free Software Foundation, either
   9 -- version 3 of the License, or (at your option) any later version.
  10 --
  11 -- This program is distributed in the hope that it will be useful,
  12 -- but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 -- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 -- GNU Affero General Public License for more details.
  15 --
  16 -- You should have received a copy of the GNU Affero General
  17 -- Public License along with this program.  If not, see
  18 -- <http://www.gnu.org/licenses/>.
  19 --
  20
  21 local CBSNews = {} -- Utility functions unique to this script
  22
  23 -- Identify the script.
  24 function ident(qargs)
  25   return {
  26     can_parse_url = CBSNews.can_parse_url(qargs),
  27     domains = table.concat({'cbsnews.com'}, ',')
  28   }
  29 end
  30
  31 -- Parse media properties.
  32 function parse(qargs)
  33   local c = CBSNews.get_data(qargs)
  34
  35   local L = require 'quvi/lxph'
  36   local U = require 'quvi/util'
  37   local P = require 'lxp.lom'
  38
  39   local x = P.parse(c)
  40
  41   local v = CBSNews.parse_optional(qargs, x, U, L)
  42
  43   qargs.streams = CBSNews.iter_streams(U, L, v)
  44
  45   return qargs
  46 end
  47
  48 --
  49 -- Utility functions
  50 --
  51
  52 function CBSNews.can_parse_url(qargs)
  53   local U = require 'socket.url'
  54   local t = U.parse(qargs.input_url)
  55   if t and t.scheme and t.scheme:lower():match('^http$')
  56        and t.host   and t.host:lower():match('cbsnews%.com$')
  57        and t.path   and t.path:lower():match('^/video/watch/')
  58        and t.query  and t.query:lower():match('^id=%w+$')
  59   then
  60     return true
  61   else
  62     return false
  63   end
  64 end
  65
  66 -- Queries the video data from the server.
  67 function CBSNews.get_data(qargs)
  68   local p = quvi.http.fetch(qargs.input_url).data
  69
  70   -- Make mandatory for the reason we need it to fetch the config.
  71   qargs.id = qargs.input_url:match('id=(%d+)') or error('no match: media ID')
  72
  73   local s = "http://api.cnet.com/restApi/v1.0/videoSearch?videoIds=%s"
  74               .. "&iod=videoMedia"
  75
  76   return quvi.http.fetch(string.format(s, qargs.id)).data
  77 end
  78
  79 -- Parse optional properties, e.g. title.
  80 function CBSNews.parse_optional(qargs, x, U, L)
  81   local v = L.find_first_tag(L.find_first_tag(x, 'Videos'), 'Video')
  82
  83   qargs.title = U.trim(L.find_first_tag(v, 'Title')[1]) or ''
  84
  85   local t = L.find_first_tag(v, 'ThumbnailImage')
  86   qargs.thumb_url = U.trim(L.find_first_tag(t, 'ImageURL')[1]) or ''
  87
  88   return v
  89 end
  90
  91 -- Iterates the available streams.
  92 function CBSNews.iter_streams(U, L, v)
  93   local m = L.find_first_tag(v, 'VideoMedias')
  94   local S = require 'quvi/stream'
  95   local r = {}
  96
  97   for i=1, #m do
  98     if m[i].tag == 'VideoMedia' then
  99       local u = U.trim(L.find_first_tag(m[i], 'DeliveryUrl')[1])
 100       local t = S.stream_new(u)
 101       t.video.bitrate_kbit_s = tonumber(L.find_first_tag(m[i], 'BitRate')[1])
 102       t.video.height =  tonumber(L.find_first_tag(m[i], 'Height')[1])
 103       t.video.width = tonumber(L.find_first_tag(m[i], 'Width')[1])
 104       t.video.encoding = ''
 105       t.container = u:match('%.(%w+)$') or ''
 106       t.id = CBSNews.to_id(t)
 107       table.insert(r, t)
 108     end
 109   end
 110
 111   if #r >1 then
 112     CBSNews.ch_best(S, r) -- Pick a stream that of the 'best' quality.
 113   end
 114
 115   return r
 116 end
 117
 118 -- Return an ID for a stream.
 119 function CBSNews.to_id(t)
 120   return string.format("%s_%dk_%dp", t.container,
 121                                      t.video.bitrate_kbit_s,
 122                                      t.video.height)
 123 end
 124
 125 -- Picks the stream with the highest video height property.
 126 function CBSNews.ch_best(S, t)
 127   local r = t[1] -- Set the first stream as the default 'best'.
 128   r.flags.best = true
 129   for _,v in pairs(t) do
 130     if v.video.height > r.video.height then
 131       r = S.swap_best(r, v)
 132     end
 133   end
 134 end
 135
 136 -- vim: set ts=2 sw=2 tw=72 expandtab: