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 L = require 'quvi/lxph'
  41   local P = require 'lxp.lom'
  42
  43   local max_results = 25
  44   local start_index = 1
  45
  46   qargs.media = {}
  47   local r = {}
  48
  49   repeat -- Get the entire playlist.
  50     local u = YouTube.config_url(qargs, start_index, max_results)
  51     local c = quvi.http.fetch(u).data
  52     local x = P.parse(c)
  53
  54     YouTube.chk_error_resp(x)
  55
  56     YouTube.parse_thumb_url(qargs, L, x)
  57     YouTube.parse_title(qargs, L, x)
  58
  59     local n = YouTube.parse_media_urls(qargs, L, x)
  60
  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, start_index, max_results)
  86   return string.format( -- Refer to http://is.gd/0msY8X
  87     'http://gdata.youtube.com/feeds/api/playlists/%s?v=2'
  88     .. '&start-index=%s&max-results=%s&strict=true',
  89       qargs.id, start_index, max_results)
  90 end
  91
  92 function YouTube.entry_avail(x)
  93   --[[
  94   -- app:control may contain, for example:
  95   --  yt:state name='restricted' reasonCode='private'
  96   ]]--
  97   for i=1, #x do
  98     if x[i].tag == 'app:control' then return false end
  99   end
 100   return true
 101 end
 102
 103 function YouTube.parse_entry(qargs, L, x, i, r)
 104   for j=1, #x[i] do
 105     if x[i][j].tag == 'link' then
 106       if x[i][j].attr['rel'] == 'alternate' then
 107         local t = {
 108           title = L.find_first_tag(x[i], 'title')[1],
 109           duration_ms = YouTube.parse_duration(L, x[i]),
 110           url = x[i][j].attr['href']
 111         }
 112         table.insert(qargs.media, t)
 113       end
 114     end
 115   end
 116 end
 117
 118 function YouTube.parse_media_urls(qargs, L, x)
 119   if not x then return 0 end
 120   local n = 0
 121   for i=1, #x do
 122     if x[i].tag == 'entry' then
 123       if YouTube.entry_avail(x[i]) then
 124         YouTube.parse_entry(qargs, L, x, i, r)
 125       end
 126       n = n+1
 127     end
 128   end
 129   return n
 130 end
 131
 132 function YouTube.chk_error_resp(t)
 133   if not t then return end
 134   local r = {}
 135   for i=1, #t do
 136     if t[i].tag == 'error' then
 137       for j=1, #t[i] do
 138         if t[i][j].tag == 'domain' then
 139           r.domain = t[i][j][1]
 140         end
 141         if t[i][j].tag == 'code' then
 142           r.code = t[i][j][1]
 143         end
 144         if t[i][j].tag == 'internalReason' then
 145           r.reason = t[i][j][1]
 146         end
 147         if t[i][j].tag == 'location' then -- Ignores 'type' attribute.
 148           r.location = t[i][j][1]
 149         end
 150       end
 151     end
 152   end
 153   if #r >0 then
 154     local m
 155     for k,v in pairs(r) do
 156       m = m .. string.format("%s=%s ", k,v)
 157     end
 158     error(m)
 159   end
 160 end
 161
 162 function YouTube.parse_title(qargs, L, x)
 163   if not qargs.title then
 164     qargs.title = L.find_first_tag(x, 'title')[1]
 165   end
 166 end
 167
 168 function YouTube.parse_thumb_url(qargs, L, x)
 169   if qargs.thumb_url then return end
 170   local g = L.find_first_tag(x, 'media:group')
 171   for i=1, #g do
 172     if g[i].tag == 'media:thumbnail' then
 173       if g[i].attr['yt:name'] == 'hqdefault' then
 174         qargs.thumb_url = g[i].attr['url']
 175         break
 176       end
 177     end
 178   end
 179 end
 180
 181 function YouTube.parse_duration(L, x)
 182   local g = L.find_first_tag(x, 'media:group')
 183   local d = L.find_first_tag(g, 'yt:duration')
 184   return tonumber(d.attr['seconds']) * 1000
 185 end
 186
 187 -- vim: set ts=2 sw=2 tw=72 expandtab: