diff options
Diffstat (limited to 'kafka/client_async.py')
| -rw-r--r-- | kafka/client_async.py | 45 |
1 files changed, 19 insertions, 26 deletions
diff --git a/kafka/client_async.py b/kafka/client_async.py index 5a1d624..d70e4f2 100644 --- a/kafka/client_async.py +++ b/kafka/client_async.py @@ -152,8 +152,8 @@ class KafkaClient(object): conn = self._conns[node_id] return conn.state is ConnectionStates.DISCONNECTED and not conn.blacked_out() - def _initiate_connect(self, node_id): - """Initiate a connection to the given node (must be in metadata)""" + def _maybe_connect(self, node_id): + """Idempotent non-blocking connection attempt to the given node id.""" if node_id not in self._conns: broker = self.cluster.broker_metadata(node_id) assert broker, 'Broker id %s not in current metadata' % node_id @@ -164,22 +164,21 @@ class KafkaClient(object): host, port, afi = get_ip_port_afi(broker.host) self._conns[node_id] = BrokerConnection(host, broker.port, afi, **self.config) - return self._finish_connect(node_id) - - def _finish_connect(self, node_id): - assert node_id in self._conns, '%s is not in current conns' % node_id state = self._conns[node_id].connect() if state is ConnectionStates.CONNECTING: self._connecting.add(node_id) + + # Whether CONNECTED or DISCONNECTED, we need to remove from connecting elif node_id in self._connecting: log.debug("Node %s connection state is %s", node_id, state) self._connecting.remove(node_id) + # Connection failures imply that our metadata is stale, so let's refresh if state is ConnectionStates.DISCONNECTED: log.warning("Node %s connect failed -- refreshing metadata", node_id) self.cluster.request_update() - return state + return self._conns[node_id].connected() def ready(self, node_id): """Check whether a node is connected and ok to send more requests. @@ -190,19 +189,15 @@ class KafkaClient(object): Returns: bool: True if we are ready to send to the given node """ - if self.is_ready(node_id): - return True - - if self._can_connect(node_id): - # if we are interested in sending to a node - # and we don't have a connection to it, initiate one - self._initiate_connect(node_id) - - if node_id in self._connecting: - self._finish_connect(node_id) - + self._maybe_connect(node_id) return self.is_ready(node_id) + def connected(self, node_id): + """Return True iff the node_id is connected.""" + if node_id not in self._conns: + return False + return self._conns[node_id].connected() + def close(self, node_id=None): """Closes the connection to a particular node (if there is one). @@ -295,15 +290,13 @@ class KafkaClient(object): request (Struct): request object (not-encoded) Raises: - NodeNotReadyError: if node_id is not ready + AssertionError: if node_id is not in current cluster metadata Returns: - Future: resolves to Response struct + Future: resolves to Response struct or Error """ - if not self._can_send_request(node_id): - raise Errors.NodeNotReadyError("Attempt to send a request to node" - " which is not ready (node id %s)." - % node_id) + if not self._maybe_connect(node_id): + return Future().failure(Errors.NodeNotReadyError(node_id)) # Every request gets a response, except one special case: expect_response = True @@ -341,7 +334,7 @@ class KafkaClient(object): # Attempt to complete pending connections for node_id in list(self._connecting): - self._finish_connect(node_id) + self._maybe_connect(node_id) # Send a metadata request if needed metadata_timeout_ms = self._maybe_refresh_metadata() @@ -557,7 +550,7 @@ class KafkaClient(object): elif self._can_connect(node_id): log.debug("Initializing connection to node %s for metadata request", node_id) - self._initiate_connect(node_id) + self._maybe_connect(node_id) return 0 |