This is a substantial release. Although there are no known 'showstopper' bugs as of release, we do recommend you test any planned upgrade to your application prior to running in production.

Some of the major changes include:

• We have officially dropped python 2.6 support
• The KafkaConsumer now includes a background thread to handle coordinator heartbeats
• API protocol handling has been separated from networking code into a new class, KafkaProtocol
• Added support for kafka message format v2
• Refactored DNS lookups during kafka broker connections
• SASL authentication is working (we think)
• Removed several circular references to improve gc on close()

Thanks to all contributors -- the state of the kafka-python community is strong!

Detailed changelog are listed below:

Client

• Fixes for SASL support
  • Refactor SASL/gssapi support (dpkp #1248 #1249 #1257 #1262 #1280)
  • Add security layer negotiation to the GSSAPI authentication (asdaraujo #1283)
  • Fix overriding sasl_kerberos_service_name in KafkaConsumer / KafkaProducer (natedogs911 #1264)
  • Fix typo in _try_authenticate_plain (everpcpc #1333)
  • Fix for Python 3 byte string handling in SASL auth (christophelec #1353)
• Move callback processing from BrokerConnection to KafkaClient (dpkp #1258)
• Use socket timeout of request_timeout_ms to prevent blocking forever on send (dpkp #1281)
• Refactor dns lookup in BrokerConnection (dpkp #1312)
• Read all available socket bytes (dpkp #1332)
• Honor reconnect_backoff in conn.connect() (dpkp #1342)

Consumer

• KAFKA-3977: Defer fetch parsing for space efficiency, and to raise exceptions to user (dpkp #1245)
• KAFKA-4034: Avoid unnecessary consumer coordinator lookup (dpkp #1254)
• Handle lookup_coordinator send failures (dpkp #1279)
• KAFKA-3888 Use background thread to process consumer heartbeats (dpkp #1266)
• Improve KafkaConsumer cleanup (dpkp #1339)
• Fix coordinator join_future race condition (dpkp #1338)
• Avoid KeyError when filtering fetchable partitions (dpkp #1344)
• Name heartbeat thread with group_id; use backoff when polling (dpkp #1345)
• KAFKA-3949: Avoid race condition when subscription changes during rebalance (dpkp #1364)
• Fix #1239 regression to avoid consuming duplicate compressed messages from mid-batch (dpkp #1367)

Producer

• Fix timestamp not passed to RecordMetadata (tvoinarovskyi #1273)
• Raise non-API exceptions (jeffwidman #1316)
• Fix reconnect_backoff_max_ms default config bug in KafkaProducer (YaoC #1352)

Core / Protocol

• Add kafka.protocol.parser.KafkaProtocol w/ receive and send (dpkp #1230)
• Refactor MessageSet and Message into LegacyRecordBatch to later support v2 message format (tvoinarovskyi #1252)
• Add DefaultRecordBatch implementation aka V2 message format parser/builder. (tvoinarovskyi #1185)
• optimize util.crc32 (ofek #1304)
• Raise better struct pack/unpack errors (jeffwidman #1320)
• Add Request/Response structs for kafka broker 1.0.0 (dpkp #1368)

Bugfixes

• use python standard max value (lukekingbru #1303)
• changed for to use enumerate() (TheAtomicOption #1301)
• Explicitly check for None rather than falsey (jeffwidman #1269)
• Minor Exception cleanup (jeffwidman #1317)
• Use non-deprecated exception handling (jeffwidman a699f6a)
• Remove assertion with side effect in client.wakeup() (bgedik #1348)
• use absolute imports everywhere (kevinkjt2000 #1362)

Test Infrastructure

• Use 0.11.0.2 kafka broker for integration testing (dpkp #1357 #1244)
• Add a Makefile to help build the project, generate docs, and run tests (tvoinarovskyi #1247)
• Add fixture support for 1.0.0 broker (dpkp #1275)
• Add kafka 1.0.0 to travis integration tests (dpkp #1365)
• Change fixture default host to localhost (asdaraujo #1305)
• Minor test cleanups (dpkp #1343)
• Use latest pytest 3.4.0, but drop pytest-sugar due to incompatibility (dpkp #1361)

Documentation

• Expand metrics docs (jeffwidman #1243)
• Fix docstring (jeffwidman #1261)
• Added controlled thread shutdown to example.py (TheAtomicOption #1268)
• Add license to wheel (jeffwidman #1286)
• Use correct casing for MB (jeffwidman #1298)

Logging / Error Messages

• Fix two bugs in printing bytes instance (jeffwidman #1296)