share/lua/playlist/youtube.lua

   1 -- libquvi-scripts
   2 -- Copyright (C) 2012  Toni Gundogdu <legatvs@gmail.com>
   3 --
   4 -- This file is part of libquvi-scripts <http://quvi.sourceforge.net/>.
   5 --
   6 -- This library is free software; you can redistribute it and/or
   7 -- modify it under the terms of the GNU Lesser General Public
   8 -- License as published by the Free Software Foundation; either
   9 -- version 2.1 of the License, or (at your option) any later version.
  10 --
  11 -- This library 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 GNU
  14 -- Lesser General Public License for more details.
  15 --
  16 -- You should have received a copy of the GNU Lesser General Public
  17 -- License along with this library; if not, write to the Free Software
  18 -- Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19 -- 02110-1301  USA
  20 --
  21
  22 local YouTube = {} -- Utility functions unique to this script
  23
  24 -- Identify the playlist script.
  25 function ident(qargs)
  26   local A = require 'quvi/accepts'
  27   local r = {
  28     accepts = A.accepts(qargs.input_url, {"youtube%.com"}, nil, {"list=%w+"})
  29   }
  30   return r
  31 end
  32
  33 -- Parse playlist properties.
  34 function parse(qargs)
  35
  36   qargs.id = qargs.input_url:match('list=(%w+)')
  37   while #qargs.id > 16 do -- Strip playlist ID prefix (e.g. "PL")
  38     qargs.id = qargs.id:gsub("^%w", "")
  39   end
  40   if #qargs.id < 16 then
  41     error('no match: playlist ID')
  42   end
  43
  44   local Y = require 'quvi/youtube'
  45   local P = require 'lxp.lom'
  46
  47   local max_results = 25
  48   local start_index = 1
  49
  50   qargs.media_url = {}
  51   local t = {}
  52
  53   repeat -- Get the entire playlist.
  54     local u = YouTube.config_url(qargs, start_index, max_results)
  55     local c = quvi.fetch(u, {type='playlist'})
  56     local r = P.parse(c)
  57
  58     YouTube.chk_error_resp(r)
  59     t = YouTube.parse_media_urls(r)
  60
  61     for _,u in pairs(t) do Y.append_if_unique(qargs, u) end
  62
  63     start_index = start_index + #t
  64   until #t == 0
  65
  66   return qargs
  67 end
  68
  69 --
  70 -- Utility functions
  71 --
  72
  73 function YouTube.config_url(qargs, start_index, max_results)
  74   return string.format( -- Refer to http://is.gd/0msY8X
  75     'http://gdata.youtube.com/feeds/api/playlists/%s?v=2'
  76     .. '&start-index=%s&max-results=%s&strict=true',
  77       qargs.id, start_index, max_results)
  78 end
  79
  80 function YouTube.parse_media_urls(t)
  81   local r = {}
  82   if not t then return r end
  83   for i=1, #t do
  84     if t[i].tag == 'entry' then
  85       for j=1, #t[i] do
  86         if t[i][j].tag == 'link' then
  87           if t[i][j].attr['rel'] == 'alternate' then
  88             table.insert(r, t[i][j].attr['href'])
  89           end
  90         end
  91       end
  92     end
  93   end
  94   return r
  95 end
  96
  97 function YouTube.chk_error_resp(t)
  98   if not t then return end
  99   local r = {}
 100   for i=1, #t do
 101     if t[i].tag == 'error' then
 102       for j=1, #t[i] do
 103         if t[i][j].tag == 'domain' then
 104           r.domain = t[i][j][1]
 105         end
 106         if t[i][j].tag == 'code' then
 107           r.code = t[i][j][1]
 108         end
 109         if t[i][j].tag == 'internalReason' then
 110           r.reason = t[i][j][1]
 111         end
 112         if t[i][j].tag == 'location' then -- Ignores 'type' attribute.
 113           r.location = t[i][j][1]
 114         end
 115       end
 116     end
 117   end
 118   if #r >0 then
 119     local m
 120     for k,v in pairs(r) do
 121       m = m .. string.format("%s=%s ", k,v)
 122     end
 123     error(m)
 124   end
 125 end
 126
 127 -- vim: set ts=2 sw=2 tw=72 expandtab: