commit 65cd34c5d735f968b03c6e618db4e177ed80f1ac
parent 535267857601e4962d57108d5c7a755166a4ecff
Author: Ricardo Garcia <sarbalap+freshmeat@gmail.com>
Date: Sun, 27 Jul 2008 12:13:49 +0200
Add initial version of postprocessing framework
Diffstat:
| M | youtube-dl | | | 86 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |
1 file changed, 86 insertions(+), 0 deletions(-)
diff --git a/youtube-dl b/youtube-dl
@@ -42,6 +42,14 @@ class SameFileError(Exception):
"""
pass
+class PostProcessingError(Exception):
+ """Post Processing exception.
+
+ This exception may be raised by PostProcessor's .run() method to
+ indicate an error in the postprocessing task.
+ """
+ pass
+
class FileDownloader(object):
"""File Downloader class.
@@ -83,10 +91,12 @@ class FileDownloader(object):
_params = None
_ies = []
+ _pps = []
def __init__(self, params):
"""Create a FileDownloader object with the given options."""
self._ies = []
+ self._pps = []
self.set_params(params)
@staticmethod
@@ -176,6 +186,11 @@ class FileDownloader(object):
self._ies.append(ie)
ie.set_downloader(self)
+ def add_post_processor(self, pp):
+ """Add a PostProcessor object to the end of the chain."""
+ self._pps.append(pp)
+ pp.set_downloader(self)
+
def to_stdout(self, message, skip_eol=False):
"""Print message to stdout if not in quiet mode."""
if not self._params.get('quiet', False):
@@ -288,11 +303,26 @@ class FileDownloader(object):
except (urllib2.URLError, httplib.HTTPException, socket.error), err:
retcode = self.trouble('ERROR: unable to download video data: %s' % str(err))
continue
+ try:
+ self.post_process(filename, result)
+ except (PostProcessingError), err:
+ retcode = self.trouble('ERROR: postprocessing: %s' % str(err))
+ continue
+
break
if not suitable_found:
retcode = self.trouble('ERROR: no suitable InfoExtractor: %s' % url)
return retcode
+
+ def post_process(self, filename, ie_info):
+ """Run the postprocessing chain on the given file."""
+ info = dict(ie_info)
+ info['filepath'] = filename
+ for pp in self._pps:
+ info = pp.run(info)
+ if info is None:
+ break
def _do_download(self, stream, url):
request = urllib2.Request(url, None, std_headers)
@@ -736,6 +766,62 @@ class YoutubePlaylistIE(InfoExtractor):
information.extend(self._youtube_ie.extract('http://www.youtube.com/watch?v=%s' % id))
return information
+class PostProcessor(object):
+ """Post Processor class.
+
+ PostProcessor objects can be added to downloaders with their
+ add_post_processor() method. When the downloader has finished a
+ successful download, it will take its internal chain of PostProcessors
+ and start calling the run() method on each one of them, first with
+ an initial argument and then with the returned value of the previous
+ PostProcessor.
+
+ The chain will be stopped if one of them ever returns None or the end
+ of the chain is reached.
+
+ PostProcessor objects follow a "mutual registration" process similar
+ to InfoExtractor objects.
+ """
+
+ _downloader = None
+
+ def __init__(self, downloader=None):
+ self._downloader = downloader
+
+ def to_stdout(self, message):
+ """Print message to stdout if downloader is not in quiet mode."""
+ if self._downloader is None or not self._downloader.get_params().get('quiet', False):
+ print message
+
+ def to_stderr(self, message):
+ """Print message to stderr."""
+ print >>sys.stderr, message
+
+ def set_downloader(self, downloader):
+ """Sets the downloader for this PP."""
+ self._downloader = downloader
+
+ def run(self, information):
+ """Run the PostProcessor.
+
+ The "information" argument is a dictionary like the ones
+ returned by InfoExtractors. The only difference is that this
+ one has an extra field called "filepath" that points to the
+ downloaded file.
+
+ When this method returns None, the postprocessing chain is
+ stopped. However, this method may return an information
+ dictionary that will be passed to the next postprocessing
+ object in the chain. It can be the one it received after
+ changing some fields.
+
+ In addition, this method may raise a PostProcessingError
+ exception that will be taken into account by the downloader
+ it was called from.
+ """
+ return information # by default, do nothing
+
+### MAIN PROGRAM ###
if __name__ == '__main__':
try:
# Modules needed only when running the main program
