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()
page_data_url = "http://www.youtube.com/watch?v=#{video_id}"
page_data = self.get_page_data(page_data_url)
- # Magic.
- t_parameter = self.parse_t_parameter(page_data)
-
- video_url = "http://www.youtube.com/get_video?video_id=#{video_id}&t=#{t_parameter}"
-
- # Figure out which formats are available, and if any are,
- # choose the best one.
- available_formats = get_available_formats(page_data)
- desired_format = get_desired_format(available_formats)
-
- if not desired_format.nil?
+ 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 stick the format parameter on the end of the URL.
- video_url = video_url + "&fmt=#{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 => e
+ # 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
#
# 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()
- # Return nil if we get no matches below.
- video_id = nil
-
# 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.
# 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)
- video_id = second_form_matches[1] if not (second_form_matches.nil? ||
- second_form_matches.length < 2)
-
- return video_id
+ return second_form_matches[1] if not (second_form_matches.nil? ||
+ second_form_matches.length < 2)
+
+ # ...and the third.
+ third_form_video_id_regex = /\/([[:alnum:]]+)$/i
+ third_form_matches = third_form_video_id_regex.match(@url)
+ return third_form_matches[1] if not (third_form_matches.nil? ||
+ third_form_matches.length < 2)
+
+ # 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
- # Parse out the "t" parameter from the video's page. I'm not sure
- # what "t" stands for, but it's located in some JSON, and is required
- # for the final video URL to work.
- def parse_t_parameter(page_data)
- t_parameter = nil
-
- t_parameter_regex = /\"t\"\:[[:space:]]\"([^\"]+?)\"/
- matches = t_parameter_regex.match(page_data)
- t_parameter = matches[1] if not (matches.nil? || matches.length < 2)
- return t_parameter
- end
-
-
- def get_available_formats(page_data)
- # Parse the list of available formats from the "fmt_list" Flash
- # variable.
- available_formats = []
- fmt_list_regex = /\"fmt_list\"\:[[:space:]]\"([^\"]+?)\"/
- matches = fmt_list_regex.match(page_data)
-
- if matches.nil?
- return nil
- else
- fmts_string = CGI::unescape(matches[1])
-
- fmts_string.split(',').each do |fmt|
- # Each "fmt" will look something like,
- #
- # 35/640000/9/0/115
- #
- # with the format identifier coming before the first slash.
- first_slash_idx = fmt.index('/')
- available_formats << fmt[0...first_slash_idx].to_i
- 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
-
- return available_formats
+
+ # 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
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