def __init__(self, brokers):
super(Client, self).__init__()
self.cluster = Cluster(brokers)
self.heal_cluster = False
self.closing = False
def __init__(self, brokers):
super(Client, self).__init__()
self.cluster = Cluster(brokers)
self.heal_cluster = False
self.closing = False
class Client(object):
"""
Base class for all client classes.
Handles basic cluster management and request sending.
"""
def __init__(self, brokers):
super(Client, self).__init__()
self.cluster = Cluster(brokers)
self.heal_cluster = False
self.closing = False
@gen.coroutine
def connect(self):
"""
Starts the underlying cluster, connecting and gathering metadata.
"""
self.cluster.abort()
yield self.cluster.start()
@gen.coroutine
def close(self):
"""
Marks a client as closing and winds down connections.
Calls the ``wind_down()`` coroutine that subclasses must implement.
"""
self.closing = True
yield self.wind_down()
self.cluster.stop()
@gen.coroutine
def wind_down(self):
"""
Cleanup method left to subclasses to define.
Called by ``close()``, should clean up any subclass-specific resources.
"""
raise NotImplementedError
@gen.coroutine
def send(self, request_by_broker):
"""
Sends a dict of requests keyed on broker ID and handles responses.
Returns a dictionary of the results of
``handle_<response.api>_response`` method calls, keyed to the
corresponding broker ID.
Raises ``UnhandledResponseError`` if the client subclass does not have
a ``handle_<response.api>_response`` method available to handle an
incoming response object.
If an error occurs in a response, the ``heal_cluster`` flag is set
and the ``heal()`` method on the cluster is called after processing
each response.
Responses are handled in the order they come in, but this method does
not yield a value until all responses are handled.
"""
iterator = gen.WaitIterator(
**{
str(broker_id): self.cluster[broker_id].send(request)
for broker_id, request in six.iteritems(request_by_broker)
})
results = {}
while not iterator.done():
self.heal_check = time.time()
try:
response = yield iterator.next()
except BrokerConnectionError as e:
log.info("Connection to %s:%s lost", e.host, e.port)
self.heal_cluster = True
break
except iostream.StreamClosedError:
log.info("Connection to broker lost.")
self.heal_cluster = True
break
except Exception:
log.exception("Error sending request.")
self.heal_cluster = True
continue
self.heal_check = time.time()
handler = getattr(self, "handle_%s_response" % response.api, None)
if handler is None:
raise UnhandledResponseError(response.api)
result = yield gen.maybe_future(handler(response))
results[int(iterator.current_index)] = result
if self.heal_cluster:
self.heal_cluster = False
yield self.cluster.heal()
raise gen.Return(results)
class Client(object):
"""
Base class for all client classes.
Handles basic cluster management and request sending.
"""
def __init__(self, brokers):
super(Client, self).__init__()
self.cluster = Cluster(brokers)
self.heal_cluster = False
self.closing = False
@gen.coroutine
def connect(self):
"""
Starts the underlying cluster, connecting and gathering metadata.
"""
yield self.cluster.start()
@gen.coroutine
def close(self):
"""
Marks a client as closing and winds down connections.
Calls the ``wind_down()`` coroutine that subclasses must implement.
"""
self.closing = True
yield self.wind_down()
self.cluster.stop()
@gen.coroutine
def wind_down(self):
"""
Cleanup method left to subclasses to define.
Called by ``close()``, should clean up any subclass-specific resources.
"""
raise NotImplementedError
@gen.coroutine
def send(self, request_by_broker):
"""
Sends a dict of requests keyed on broker ID and handles responses.
Returns a dictionary of the results of
``handle_<response.api>_response`` method calls, keyed to the
corresponding broker ID.
Raises ``UnhandledResponseError`` if the client subclass does not have
a ``handle_<response.api>_response`` method available to handle an
incoming response object.
If an error occurs in a response, the ``heal_cluster`` flag is set
and the ``heal()`` method on the cluster is called after processing
each response.
Responses are handled in the order they come in, but this method does
not yield a value until all responses are handled.
"""
iterator = gen.WaitIterator(**{
str(broker_id): self.cluster[broker_id].send(request)
for broker_id, request in six.iteritems(request_by_broker)
})
results = {}
while not iterator.done():
try:
response = yield iterator.next()
except BrokerConnectionError as e:
log.info("Connection to %s:%s lost", e.host, e.port)
self.heal_cluster = True
continue
except iostream.StreamClosedError:
log.info("Connection to broker lost.")
continue
except Exception:
log.exception("Error sending request.")
self.heal_cluster = True
continue
handler = getattr(self, "handle_%s_response" % response.api, None)
if handler is None:
raise UnhandledResponseError(response.api)
result = yield gen.maybe_future(handler(response))
results[int(iterator.current_index)] = result
if self.heal_cluster:
yield self.cluster.heal()
self.heal_cluster = False
raise gen.Return(results)