+++ /dev/null
-#
-# Copyright Michael Orlitzky
-#
-# http://michael.orlitzky.com/
-#
-# This program is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-# GNU General Public License for more details.
-#
-# http://www.fsf.org/licensing/licenses/gpl.html
-#
-
-require 'src/website'
-require 'cgi'
-
-class Youtube < Website
-
- VALID_YOUTUBE_URL_REGEX = /^(http:\/\/)?([a-z0-9]+\.)?youtube\.com\/((watch\?v=)|(v\/)|([a-z]+\#[a-z]\/[a-z]\/[0-9]\/))[a-z0-9_\-]+(\&.*)?\#?$/i
-
- def self.owns_url?(url)
- return url =~ VALID_YOUTUBE_URL_REGEX
- end
-
-
- def initialize(url)
- super
-
- # The @format variable just caches the format of the video we're
- # downloading. Storing it will prevent us from having to calculate
- # it twice.
- @format = 0
- end
-
-
- def get_video_url()
- video_id = self.parse_video_id()
-
- # The video's URL (the "page data" URL) may be different from the
- # URL that was passed to the program. We support the /v/video_id
- # URL format, but that is *not* the main video page where we can
- # retrieve the "t" parameter. We can only get that from the
- # /watch?v=video_id form.
- page_data_url = "http://www.youtube.com/watch?v=#{video_id}"
- page_data = self.get_page_data(page_data_url)
-
- begin
- # Get the URL map from the page.
- fmt_url_map = get_format_url_map(page_data)
-
- # Figure out which formats are available, and if any are,
- # choose the best one.
- available_formats = fmt_url_map.keys()
- desired_format = get_desired_format(available_formats)
-
- # First we cache the format so that when we're asked for the
- # video filename later, we don't have to recompute the format.
- @format = desired_format
-
- # And then use whatever URL is available for the desired format.
- # We assume that all available formats will have an entry in the
- # fmt_url_map hash.
- video_url = fmt_url_map[desired_format]
- return video_url
- rescue StandardError
- # If at first you do not succeed, maybe someone decided to
- # change some shit. This alternate method parses
- # url_encoded_fmt_stream_map.
- fmt_streams = get_fmt_stream_list(page_data)
- video_url = self.choose_best_fmt_stream_url(fmt_streams)
-
- # A duplicated "itag" parameter results in a 403.
- itag_regex = /&itag=\d+/
- matches = video_url.scan(itag_regex)
-
- if matches.length > 1
- # Get rid of the first occurrence.
- video_url.sub!(itag_regex, '')
- end
- end
-
- return video_url
- end
-
-
- def get_video_filename()
- # The format -> extension mapping is available on Wikipedia:
- #
- # http://en.wikipedia.org/wiki/YouTube#Quality_and_codecs
- #
- # The default extension is .flv.
- extension = '.flv'
-
- if [18, 22, 35, 37].include?(@format)
- extension = '.mp4'
- elsif (@format == 17)
- extension = '.3gp'
- end
-
- return (self.parse_video_id() + extension)
- end
-
-
- protected;
-
- def choose_best_fmt_stream_url(fmt_stream_urls)
- # Take a list, generated by get_fmt_stream_list(), and choose the
- # best URL out of the bunch based on the video format.
- fmt_stream_urls.each do |fs|
- if fs =~ /video\/mp4/ and fs =~ /quality=large/
- return fs
- elsif fs =~ /quality=large/
- return fs
- elsif fs =~ /video\/mp4/
- return fs
- else
- return fs
- end
- end
- end
-
-
- def unicode_unescape(string)
- # Unescape sequences like '\u0026'.
- # Ok, only '\u0026' for now.
- return string.gsub('\u0026', '&')
- end
-
-
- def get_fmt_stream_list(page_data)
- # This is another (new?) method of embedding the video URLs.
- # The url_encoded_fmt_stream_map variable contains a list of URLs
- # in the form url=foo1,url=foo2...
- #
- # It looks like the first one in the list is the highest
- # quality? Let's just take that one for now.
- fmt_stream_regex = /\"url_encoded_fmt_stream_map\": \"(.+?)\"/
-
- matches = fmt_stream_regex.match(page_data)
-
- if (matches.nil? || matches.length < 2)
- raise StandardError.new("Could not parse the url_encoded_fmt_stream_map Flash variable.")
- end
-
- urlstring = matches[1]
- urlstring.gsub!('url=', '')
- urls = urlstring.split(',')
-
- urls.each_index do |idx|
- urls[idx] = self.unicode_unescape(urls[idx])
- urls[idx] = CGI::unescape(urls[idx])
- # Strip off everything after the first space in the URL.
- # I don't know why this works, but if we leave the space
- # in (encoded, even), Youtube throws us 403 errors.
- urls[idx].gsub!(/ .+$/, '')
- end
-
- return urls
- end
-
-
- # Get the video id from the URL. Should be relatively easy,
- # unless Youtube supports some URL formats of which I'm unaware.
- def parse_video_id()
- # Both URLs are fairly easy to parse if you handle
- # them one at a time. The only tricky situation is when
- # parameters like "&hl=en" are tacked on to the end.
- # We'll call /watch?v=video_id the "first form."
- first_form_video_id_regex = /v=([0-9a-z_\-]+)/i
- first_form_matches = first_form_video_id_regex.match(@url)
- if not first_form_matches.nil? || first_form_matches.length < 2
- return first_form_matches[1]
- end
-
- # First form didn't work? Try the second.
- second_form_video_id_regex = /\/v\/([0-9a-z_\-]+)/i
- second_form_matches = second_form_video_id_regex.match(@url)
- if not second_form_matches.nil? || second_form_matches.length < 2
- return second_form_matches[1]
- end
-
- # ...and the third.
- third_form_video_id_regex = /\/([[:alnum:]]+)$/i
- third_form_matches = third_form_video_id_regex.match(@url)
- if not third_form_matches.nil? || third_form_matches.length < 2
- return third_form_matches[1]
- end
-
- # If we made it here, we couldn't figure out the video id. Yes,
- # this is fatal, since we don't know where the video file is
- # located.
- raise StandardError.new("Could not parse the video id.")
- end
-
-
-
- def get_format_url_map(page_data)
- # Youtube has implemented a new fmt_url_map that (perhaps
- # unsurprisingly) maps formats to video URLs. This makes it
- # easyish to parse the video URLs.
- url_map = {}
- url_map_regex = /fmt_url_map=([^&\"]+)/
-
- matches = url_map_regex.match(page_data)
-
- if (matches.nil? || matches.length < 1)
- raise StandardError.new("Could not parse the fmt_url_map Flash variable.")
- end
-
- # The map is stored entirely in one Flash variable. The format is
- # key|value,key|value,...
- maptext = CGI::unescape(matches[1])
- entries = maptext.split(',')
- entries.each do |entry|
- key = entry.split('|')[0].to_i
- value = entry.split('|')[1]
- url_map[key] = value
- end
-
- if (url_map.length < 1)
- raise StandardError.new("Could not find any valid format URLs.")
- end
-
- return url_map
- end
-
-
- def get_desired_format(available_formats)
- # Check for the presence of formats, in order of preference
- # (quality). That is, we check for the best formats first. As soon
- # as a format is found to be available, we return it as the
- # desired format, since the first format we find is going to be
- # the best available format.
- return 37 if available_formats.include?(37)
- return 22 if available_formats.include?(22)
- return 35 if available_formats.include?(35)
- return 18 if available_formats.include?(18)
- return 34 if available_formats.include?(34)
- return 17 if available_formats.include?(17)
-
- # Available formats can't be empty (we would have raised an error
- # in get_available_formats), so if there's some unknown format
- # here we might as well return it as a last resort.
- return available_formats[0]
- end
-
-end
projects / dead / whatever-dl.git / blobdiff