def _redirect(self, new_url, old_query):
"""Update announce URL from HTTP redirect"""
if self._redirects >= self.MAX_REDIRECTS:
raise IOError(('http error', 500,
'Internal Server Error: Redirect Recursion'))
scheme, netloc, path, query, frag = urllib.parse.urlsplit(new_url)
# If we got our own query string back, remove it
oq_dict = urllib.parse.parse_qs(old_query)
new_query = urllib.parse.urlencode(
(key, val) for key, val in urllib.parse.parse_qsl(query)
if val != oq_dict.get(key, ''))
tracker_url = urllib.parse.urlunsplit(
(scheme, netloc, path, new_query, frag))
with self.announcer_lock:
# It's possible to have the same redirect happen
if tracker_url in self.announcers and \
self.announcers[tracker_url] == self:
return
self._redirects += 1
self.announcers[tracker_url] = self
self.stream = SharedStream(tracker_url)
self.basequery = path + '?' + new_query + '&'[:bool(new_query)]
def __new__(cls, tracker_url, port, *args, **kwargs):
"""Return the Announcer associated with the tracker URL, creating a
new one, if needed.
Client port is made available to Announcer objects, but is assumed
not to vary within a program, so calling with the same URL and two
different ports will return the same object."""
# Use Announcer() to allow scheme to decide on subclass
if cls is Announcer:
scheme = urllib.parse.urlsplit(tracker_url)[0]
return cls.subclasses[scheme](tracker_url, port, *args, **kwargs)
with cls.announcer_lock:
# Assume port will not change within single Python instance
# If this changes, change key to (tracker_url, port)
if tracker_url not in cls.announcers:
announcer = super(Announcer, cls).__new__(cls)
# Keys allow trackers to recognize clients with IP changes
announcer.key = random.randint(0,
0xffffffff).to_bytes(4, 'big')
announcer.stream = SharedStream(tracker_url)
cls.announcers[tracker_url] = announcer
return cls.announcers[tracker_url]
