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authorMahendra M <mahendra.m@gmail.com>2013-05-31 14:57:57 +0530
committerDavid Arthur <mumrah@gmail.com>2013-06-04 09:16:29 -0400
commit6704050e50a2934806e349ac875f2ab31ccfcd9d (patch)
treec5ebdcb8bfde25c84078dd919bf1c6b619effe63 /kafka/client.py
parent58288d9f86a67772326cf946d0ff4729a764ad52 (diff)
downloadkafka-python-6704050e50a2934806e349ac875f2ab31ccfcd9d.tar.gz
Finish making remaining files pep8 ready
Diffstat (limited to 'kafka/client.py')
-rw-r--r--kafka/client.py169
1 files changed, 109 insertions, 60 deletions
diff --git a/kafka/client.py b/kafka/client.py
index eb2c25c..5595d49 100644
--- a/kafka/client.py
+++ b/kafka/client.py
@@ -10,43 +10,47 @@ import zlib
from kafka.common import *
from kafka.conn import KafkaConnection
-from kafka.protocol import KafkaProtocol
+from kafka.protocol import KafkaProtocol
log = logging.getLogger("kafka")
+
class KafkaClient(object):
CLIENT_ID = "kafka-python"
- ID_GEN = count()
+ ID_GEN = count()
def __init__(self, host, port, bufsize=4096):
- # We need one connection to bootstrap
+ # We need one connection to bootstrap
self.bufsize = bufsize
- self.conns = { # (host, port) -> KafkaConnection
+ self.conns = { # (host, port) -> KafkaConnection
(host, port): KafkaConnection(host, port, bufsize)
- }
- self.brokers = {} # broker_id -> BrokerMetadata
- self.topics_to_brokers = {} # topic_id -> broker_id
- self.topic_partitions = defaultdict(list) # topic_id -> [0, 1, 2, ...]
+ }
+ self.brokers = {} # broker_id -> BrokerMetadata
+ self.topics_to_brokers = {} # topic_id -> broker_id
+ self.topic_partitions = defaultdict(list) # topic_id -> [0, 1, 2, ...]
self._load_metadata_for_topics()
##################
# Private API #
##################
-
def _get_conn_for_broker(self, broker):
"Get or create a connection to a broker"
if (broker.host, broker.port) not in self.conns:
- self.conns[(broker.host, broker.port)] = KafkaConnection(broker.host, broker.port, self.bufsize)
+ self.conns[(broker.host, broker.port)] = \
+ KafkaConnection(broker.host, broker.port, self.bufsize)
+
return self.conns[(broker.host, broker.port)]
def _get_leader_for_partition(self, topic, partition):
key = TopicAndPartition(topic, partition)
if key not in self.topics_to_brokers:
self._load_metadata_for_topics(topic)
+
if key not in self.topics_to_brokers:
raise Exception("Partition does not exist: %s" % str(key))
+
return self.topics_to_brokers[key]
def _load_metadata_for_topics(self, *topics):
@@ -55,13 +59,18 @@ class KafkaClient(object):
recurse in the event of a retry.
"""
requestId = self._next_id()
- request = KafkaProtocol.encode_metadata_request(KafkaClient.CLIENT_ID, requestId, topics)
+ request = KafkaProtocol.encode_metadata_request(KafkaClient.CLIENT_ID,
+ requestId, topics)
+
response = self._send_broker_unaware_request(requestId, request)
if response is None:
raise Exception("All servers failed to process request")
+
(brokers, topics) = KafkaProtocol.decode_metadata_response(response)
+
log.debug("Broker metadata: %s", brokers)
log.debug("Topic metadata: %s", topics)
+
self.brokers.update(brokers)
self.topics_to_brokers = {}
for topic, partitions in topics.items():
@@ -77,7 +86,8 @@ class KafkaClient(object):
time.sleep(1)
self._load_metadata_for_topics(topic)
else:
- self.topics_to_brokers[TopicAndPartition(topic, partition)] = brokers[meta.leader]
+ topic_part = TopicAndPartition(topic, partition)
+ self.topics_to_brokers[topic_part] = brokers[meta.leader]
self.topic_partitions[topic].append(partition)
def _next_id(self):
@@ -86,8 +96,8 @@ class KafkaClient(object):
def _send_broker_unaware_request(self, requestId, request):
"""
- Attempt to send a broker-agnostic request to one of the available brokers.
- Keep trying until you succeed.
+ Attempt to send a broker-agnostic request to one of the available
+ brokers. Keep trying until you succeed.
"""
for conn in self.conns.values():
try:
@@ -95,32 +105,43 @@ class KafkaClient(object):
response = conn.recv(requestId)
return response
except Exception, e:
- log.warning("Could not send request [%r] to server %s, trying next server: %s" % (request, conn, e))
+ log.warning("Could not send request [%r] to server %s, "
+ "trying next server: %s" % (request, conn, e))
continue
+
return None
def _send_broker_aware_request(self, payloads, encoder_fn, decoder_fn):
"""
- Group a list of request payloads by topic+partition and send them to the
- leader broker for that partition using the supplied encode/decode functions
+ Group a list of request payloads by topic+partition and send them to
+ the leader broker for that partition using the supplied encode/decode
+ functions
Params
======
- payloads: list of object-like entities with a topic and partition attribute
- encode_fn: a method to encode the list of payloads to a request body, must accept
- client_id, correlation_id, and payloads as keyword arguments
- decode_fn: a method to decode a response body into response objects. The response
- objects must be object-like and have topic and partition attributes
+ payloads: list of object-like entities with a topic and
+ partition attribute
+ encode_fn: a method to encode the list of payloads to a request body,
+ must accept client_id, correlation_id, and payloads as
+ keyword arguments
+ decode_fn: a method to decode a response body into response objects.
+ The response objects must be object-like and have topic
+ and partition attributes
Return
======
List of response objects in the same order as the supplied payloads
"""
+
# Group the requests by topic+partition
original_keys = []
payloads_by_broker = defaultdict(list)
+
for payload in payloads:
- payloads_by_broker[self._get_leader_for_partition(payload.topic, payload.partition)].append(payload)
+ leader = self._get_leader_for_partition(payload.topic,
+ payload.partition)
+
+ payloads_by_broker[leader].append(payload)
original_keys.append((payload.topic, payload.partition))
# Accumulate the responses in a dictionary
@@ -130,7 +151,8 @@ class KafkaClient(object):
for broker, payloads in payloads_by_broker.items():
conn = self._get_conn_for_broker(broker)
requestId = self._next_id()
- request = encoder_fn(client_id=KafkaClient.CLIENT_ID, correlation_id=requestId, payloads=payloads)
+ request = encoder_fn(client_id=KafkaClient.CLIENT_ID,
+ correlation_id=requestId, payloads=payloads)
# Send the request, recv the response
conn.send(requestId, request)
@@ -149,33 +171,43 @@ class KafkaClient(object):
for conn in self.conns.values():
conn.close()
- def send_produce_request(self, payloads=[], acks=1, timeout=1000, fail_on_error=True, callback=None):
+ def send_produce_request(self, payloads=[], acks=1, timeout=1000,
+ fail_on_error=True, callback=None):
"""
Encode and send some ProduceRequests
- ProduceRequests will be grouped by (topic, partition) and then sent to a specific
- broker. Output is a list of responses in the same order as the list of payloads
- specified
+ ProduceRequests will be grouped by (topic, partition) and then
+ sent to a specific broker. Output is a list of responses in the
+ same order as the list of payloads specified
Params
======
payloads: list of ProduceRequest
- fail_on_error: boolean, should we raise an Exception if we encounter an API error?
- callback: function, instead of returning the ProduceResponse, first pass it through this function
+ fail_on_error: boolean, should we raise an Exception if we
+ encounter an API error?
+ callback: function, instead of returning the ProduceResponse,
+ first pass it through this function
Return
======
- list of ProduceResponse or callback(ProduceResponse), in the order of input payloads
+ list of ProduceResponse or callback(ProduceResponse), in the
+ order of input payloads
"""
- resps = self._send_broker_aware_request(payloads,
- partial(KafkaProtocol.encode_produce_request, acks=acks, timeout=timeout),
- KafkaProtocol.decode_produce_response)
+
+ encoder = partial(KafkaProtocol.encode_produce_request,
+ acks=acks, timeout=timeout)
+ decoder = KafkaProtocol.decode_produce_response
+ resps = self._send_broker_aware_request(payloads, encoder, decoder)
+
out = []
for resp in resps:
# Check for errors
- if fail_on_error == True and resp.error != ErrorMapping.NO_ERROR:
- raise Exception("ProduceRequest for %s failed with errorcode=%d" %
- (TopicAndPartition(resp.topic, resp.partition), resp.error))
+ if fail_on_error is True and resp.error != ErrorMapping.NO_ERROR:
+ raise Exception("ProduceRequest for %s failed with "
+ "errorcode=%d" % (
+ TopicAndPartition(resp.topic, resp.partition),
+ resp.error))
+
# Run the callback
if callback is not None:
out.append(callback(resp))
@@ -183,22 +215,27 @@ class KafkaClient(object):
out.append(resp)
return out
- def send_fetch_request(self, payloads=[], fail_on_error=True, callback=None):
+ def send_fetch_request(self, payloads=[], fail_on_error=True,
+ callback=None):
"""
Encode and send a FetchRequest
-
- Payloads are grouped by topic and partition so they can be pipelined to the same
- brokers.
+
+ Payloads are grouped by topic and partition so they can be pipelined
+ to the same brokers.
"""
resps = self._send_broker_aware_request(payloads,
KafkaProtocol.encode_fetch_request,
KafkaProtocol.decode_fetch_response)
+
out = []
for resp in resps:
# Check for errors
- if fail_on_error == True and resp.error != ErrorMapping.NO_ERROR:
- raise Exception("FetchRequest for %s failed with errorcode=%d" %
- (TopicAndPartition(resp.topic, resp.partition), resp.error))
+ if fail_on_error is True and resp.error != ErrorMapping.NO_ERROR:
+ raise Exception("FetchRequest for %s failed with "
+ "errorcode=%d" % (
+ TopicAndPartition(resp.topic, resp.partition),
+ resp.error))
+
# Run the callback
if callback is not None:
out.append(callback(resp))
@@ -206,43 +243,55 @@ class KafkaClient(object):
out.append(resp)
return out
-
- def send_offset_request(self, payloads=[], fail_on_error=True, callback=None):
+ def send_offset_request(self, payloads=[], fail_on_error=True,
+ callback=None):
resps = self._send_broker_aware_request(payloads,
KafkaProtocol.encode_offset_request,
KafkaProtocol.decode_offset_response)
+
out = []
for resp in resps:
- if fail_on_error == True and resp.error != ErrorMapping.NO_ERROR:
- raise Exception("OffsetRequest failed with errorcode=%s", resp.error)
+ if fail_on_error is True and resp.error != ErrorMapping.NO_ERROR:
+ raise Exception("OffsetRequest failed with errorcode=%s",
+ resp.error)
if callback is not None:
out.append(callback(resp))
else:
out.append(resp)
return out
- def send_offset_commit_request(self, group, payloads=[], fail_on_error=True, callback=None):
- resps = self._send_broker_aware_request(payloads,
- partial(KafkaProtocol.encode_offset_commit_request, group=group),
- KafkaProtocol.decode_offset_commit_response)
+ def send_offset_commit_request(self, group, payloads=[],
+ fail_on_error=True, callback=None):
+ encoder = partial(KafkaProtocol.encode_offset_commit_request,
+ group=group)
+ decoder = KafkaProtocol.decode_offset_commit_response
+ resps = self._send_broker_aware_request(payloads, encoder, decoder)
+
out = []
for resp in resps:
- if fail_on_error == True and resp.error != ErrorMapping.NO_ERROR:
- raise Exception("OffsetCommitRequest failed with errorcode=%s", resp.error)
+ if fail_on_error is True and resp.error != ErrorMapping.NO_ERROR:
+ raise Exception("OffsetCommitRequest failed with "
+ "errorcode=%s", resp.error)
+
if callback is not None:
out.append(callback(resp))
else:
out.append(resp)
return out
- def send_offset_fetch_request(self, group, payloads=[], fail_on_error=True, callback=None):
- resps = self._send_broker_aware_request(payloads,
- partial(KafkaProtocol.encode_offset_fetch_request, group=group),
- KafkaProtocol.decode_offset_fetch_response)
+ def send_offset_fetch_request(self, group, payloads=[],
+ fail_on_error=True, callback=None):
+
+ encoder = partial(KafkaProtocol.encode_offset_fetch_request,
+ group=group)
+ decoder = KafkaProtocol.decode_offset_fetch_response
+ resps = self._send_broker_aware_request(payloads, encoder, decoder)
+
out = []
for resp in resps:
- if fail_on_error == True and resp.error != ErrorMapping.NO_ERROR:
- raise Exception("OffsetCommitRequest failed with errorcode=%s", resp.error)
+ if fail_on_error is True and resp.error != ErrorMapping.NO_ERROR:
+ raise Exception("OffsetCommitRequest failed with errorcode=%s",
+ resp.error)
if callback is not None:
out.append(callback(resp))
else: