share/playlist/youtube.lua

   1 -- libquvi-scripts
   2 -- Copyright (C) 2012-2013  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 YouTube = {} -- Utility functions unique to this script
  22
  23 -- Identify the playlist script.
  24 function ident(qargs)
  25   return {
  26     domains = table.concat({'youtube.com'}, ','),
  27     can_parse_url = YouTube.can_parse_url(qargs)
  28   }
  29 end
  30
  31 -- Parse playlist properties.
  32 function parse(qargs)
  33
  34   qargs.id = qargs.input_url:match('list=([%w_-]+)')
  35   if #qargs.id <16 then
  36     error('no match: playlist ID')
  37   end
  38
  39   local Y = require 'quvi/youtube'
  40   local U = require 'socket.url'
  41   local L = require 'quvi/lxph'
  42   local P = require 'lxp.lom'
  43
  44   local max_results = 25
  45   local start_index = 1
  46
  47   qargs.media = {}
  48   local r = {}
  49
  50   repeat -- Get the entire playlist.
  51     local u = YouTube.config_url(qargs, U, start_index, max_results)
  52     local c = quvi.http.fetch(u).data
  53
  54     local x = P.parse(c)
  55     YouTube.chk_error_resp(x)
  56
  57     YouTube.parse_thumb_url(qargs, L, x)
  58     YouTube.parse_title(qargs, L, x)
  59
  60     local n = YouTube.parse_media_urls(qargs, L, x)
  61     start_index = start_index + n
  62   until n == 0
  63
  64   return qargs
  65 end
  66
  67 --
  68 -- Utility functions
  69 --
  70
  71 function YouTube.can_parse_url(qargs)
  72   local U = require 'socket.url'
  73   local t = U.parse(qargs.input_url)
  74   if t and t.scheme and t.scheme:lower():match('^https?$')
  75        and t.host   and t.host:lower():match('youtube%.com$')
  76        and t.path   and t.path:lower():match('^/playlist$')
  77        and t.query  and t.query:lower():match('^list=[%w_-]+')
  78   then
  79     return true
  80   else
  81     return false
  82   end
  83 end
  84
  85 function YouTube.config_url(qargs, U, start_index, max_results)
  86   local u = U.parse(qargs.input_url)
  87   local t = { -- Refer to http://is.gd/0msY8X
  88     u.scheme, '://gdata.youtube.com/feeds/api/playlists/',
  89     qargs.id, '?v=2', '&start-index=', start_index,
  90     '&max-results=', max_results, '&strict=true'
  91   }
  92   return table.concat(t,'')
  93 end
  94
  95 function YouTube.entry_avail(x)
  96   --[[
  97   -- app:control may contain, for example:
  98   --  yt:state name='restricted' reasonCode='private'
  99   ]]--
 100   for i=1, #x do
 101     if x[i].tag == 'app:control' then return false end
 102   end
 103   return true
 104 end
 105
 106 function YouTube.parse_entry(qargs, L, x, i, r)
 107   for j=1, #x[i] do
 108     if x[i][j].tag == 'link' then
 109       if x[i][j].attr['rel'] == 'alternate' then
 110         local t = {
 111           title = L.find_first_tag(x[i], 'title')[1],
 112           duration_ms = YouTube.parse_duration(L, x[i]),
 113           url = x[i][j].attr['href']
 114         }
 115         table.insert(qargs.media, t)
 116       end
 117     end
 118   end
 119 end
 120
 121 function YouTube.parse_media_urls(qargs, L, x)
 122   if not x then return 0 end
 123   local n = 0
 124   for i=1, #x do
 125     if x[i].tag == 'entry' then
 126       if YouTube.entry_avail(x[i]) then
 127         YouTube.parse_entry(qargs, L, x, i, r)
 128       end
 129       n = n+1
 130     end
 131   end
 132   return n
 133 end
 134
 135 function YouTube.chk_error_resp(t)
 136   if not t then return end
 137   local r = {}
 138   for i=1, #t do
 139     if t[i].tag == 'error' then
 140       for j=1, #t[i] do
 141         if t[i][j].tag == 'domain' then
 142           r.domain = t[i][j][1]
 143         end
 144         if t[i][j].tag == 'code' then
 145           r.code = t[i][j][1]
 146         end
 147         if t[i][j].tag == 'internalReason' then
 148           r.reason = t[i][j][1]
 149         end
 150         if t[i][j].tag == 'location' then -- Ignores 'type' attribute.
 151           r.location = t[i][j][1]
 152         end
 153       end
 154     end
 155   end
 156   if #r >0 then
 157     local m
 158     for k,v in pairs(r) do
 159       m = m .. string.format("%s=%s ", k,v)
 160     end
 161     error(m)
 162   end
 163 end
 164
 165 function YouTube.parse_title(qargs, L, x)
 166   if not qargs.title then
 167     qargs.title = L.find_first_tag(x, 'title')[1]
 168   end
 169 end
 170
 171 function YouTube.parse_thumb_url(qargs, L, x)
 172   if qargs.thumb_url then return end
 173   local g = L.find_first_tag(x, 'media:group')
 174   for i=1, #g do
 175     if g[i].tag == 'media:thumbnail' then
 176       if g[i].attr['yt:name'] == 'hqdefault' then
 177         qargs.thumb_url = g[i].attr['url']
 178         break
 179       end
 180     end
 181   end
 182 end
 183
 184 function YouTube.parse_duration(L, x)
 185   local g = L.find_first_tag(x, 'media:group')
 186   local d = L.find_first_tag(g, 'yt:duration')
 187   return tonumber(d.attr['seconds']) * 1000
 188 end
 189
 190 -- vim: set ts=2 sw=2 tw=72 expandtab: