def query(self, service, num=0, timeout=10):
"""Query Notaries and return NotaryResponses instance
For any Notary not responding, a None will be in the array.
num specifies the number of Notaries to query. If 0, all notaries
are queried.
timeout is the timeout in seconds"""
if num == 0:
to_query = self
else:
if num > len(self):
raise ValueError("Too many notaries requested (%s > %s)" % (num, len(self)))
to_query = random.sample(self, num)
responses = NotaryResponses()
dispatchers = []
# Use own map here for thread safety
map = {}
for notary in to_query:
self.logger.debug("Querying %s about %s..." % (notary, service))
dispatchers.append((notary,
HTTP_dispatcher(notary.get_url(service),
map=map)))
self.logger.debug("Calling asyncore.loop()")
timed_asyncore.loop_with_timeout(timeout=timeout, map=map)
self.logger.debug("asyncore.loop() done.")
for notary, dispatcher in dispatchers:
try:
response = dispatcher.get_response()
xml = response.read()
self.logger.debug("Validating response from %s (%d bytes)" % (notary, len(xml)))
response = NotaryResponse(xml)
notary.verify_response(response, service)
self.logger.debug("Response signature verified")
responses.append(response)
except EOFError as e:
self.logger.error("Failed to get response from %s: %s" % (notary, str(e)))
responses.append(None)
except httplib.BadStatusLine as e:
self.logger.error("Failed to parse response from %s, bad status: %s" % (notary, e))
responses.append(None)
except NotaryException as e:
self.logger.error("Error validating response from %s: %s" % (notary, e))
responses.append(None)
except Exception as e:
self.logger.error("Unknown error handling response from %s: %s" % (notary, e))
responses.append(None)
return responses
def __init__(self, notary, service, map=None):
self.protocol = notary.get_protocol(service)
HTTP_dispatcher.__init__(self, self.protocol.get_url(), map=map)
def get_response(self):
"""Return NotaryResponse instance"""
response_fd = HTTP_dispatcher.get_response(self)
data = response_fd.read()
response = self.protocol.parse_response(data)
return response
