3.0.8 (Jul 9, 2026)

Fixes

• transport: Fix TLS SNI when ssl_check_hostname=False (#3114)

3.0.7 (Jun 28, 2026)

Fixes

• transport: cancel pending io coroutines on close() (#3109)
• producer: fix stalled shutdown when brokers unreachable (#3108)

3.0.6 (Jun 25, 2026)

Fixes

• consumer: track current leader epoch in addition to record epoch (#3107)

CI

• Also wait_for_topics on <0.10 test fixtures (#3105)

3.0.5 (Jun 24, 2026)

Fixes

• Reserve buffer capacity before every encode_into write (#3103)
• Fix backoff on bootstrap init failure after connection_made (#3098)

CI

• Bump actions/cache from 5 to 6 (#3099)
• only save kafka dist cache on master (#3100)
• Fix flakey test: test_send_during_backoff

Documentation

• Add new extended logging args to docs/cli

3.0.4 (Jun 23, 2026)

Fixes

• Fix _build_transport / conn.close race (#3097)
• net.transport: Fix closed/write_eof handling in _write_to_sock (#3095)
• Fix kafka.net.connection await: raise connection failures (#3091)

Logging

• bootstrap connection log changes (#3092)
• Improve connection logging; dont log version check if matches expected (#3089)
• tests: print integration fixture output to console if no log handlers

Documentation

• docs: Add title headings for KafkaConsumer/KafkaProducer; add sphinx-argparse to requirements-dev.txt (#3096)

3.0.2 (Jun 18, 2026)

Fixes

• fix memory leak of cancelled timeout tasks (@azdobylak / #3077)

3.0.1 (Jun 17, 2026)

Fixes

• receive_message_max_bytes default 100MiB (consumer/producer/admin); check against fetch_max_bytes and max_partition_fetch_bytes in Consumer (#3075)

Consumer

• Add MemberState to ConsumerGroupMetadata / consumer.group_metadata() (#3071)

Tests

• Add ConsumerGroupRunner fixture to manage multi-consumer group integration tests (#3072)
• Add MockGroup and test coordinator rebalance / metadata snapshot changes (#3069)
• Use 4.3 api_version for producer tests; fixup inadvertent sender thread leak in test (#3068)
• Add test coverage for producer acks (#3067)
• Fill-in empty sender tests (#3066)
• Add MockCluster; test failover on CoordinatorNotAvailableError (#3065)

Documentation

• Add ConsumerRecord, RecordMetadata, and FutureRecordMetadata to docs (#3070)

3.0.0 (Jun 11, 2026)

This is a major release with significant changes to kafka-python internals to simplify networking and feature development. It introduces a new networking layer (kafka.net) and a dynamic protocol system that uses JSON schema files imported from Apache Kafka. It substantially refactors and expands the Admin client, including breaking changes to some API signatures, and it lands a long list of KIP features/changes across the producer, consumer, admin, and networking/metadata clients. Protocol support across kafka-python is now at or beyond the apache kafka 3.0 baseline.

Breaking Changes

Python Compatibility

• Drop python2 support (#2699, #2774, #2837, #2846)

Default Configuration Changes

• KIP-679: Update Producer defaults -- enable_idempotence=True, acks='all' (#3013)
• KIP-735: Increase default consumer session_timeout_ms from 10s to 45s (#3030)
• Rename api_version_auto_timeout_ms -> bootstrap_timeout_ms; default 30s (#3028)
• Producer: Remove deprecation warning for buffer_memory config (now raises) (#3047)

Abstract Interface Changes

• Serializer/Deserializer: Pass headers to serialize/deserialize (#3046)
• Partitioner: pass both key/value, serialized and unserialized, to partition() (#3045)

Admin API Changes

• Admin: change response shapes to simple dicts (#2883)
• Admin: groups apis renames; add offsets, members apis (#2892)
• Admin: Deprecate NewTopics/NewPartitions in favor of simple dicts (#2869)

Consumer API Changes

• Consumer: use assignor instances, not classes (#2775)

Error Hierarchy

• KafkaError subclass Exception not RuntimeError (#2932)
• Make IncompatibleBrokerVersion a subclass of UnsupportedVersionError (#2924)
• Eliminate NoBrokersAvailableError (#2942)
• KafkaProtocolError is not retriable (#2941)
• Prefer raised Exceptions to assert / AssertionError (#3042)

Old Networking Stack Removal

• Remove kafka.client_async / kafka.conn legacy modules (#2918)
• Drop version probes for pre-0.10/ApiVersionsRequest brokers

SASL Module Rename

• Rename kafka.sasl -> kafka.net.sasl

Networking (kafka.net)

Complete refactor of the networking layer using a bespoke event-loop supporting async/await (but no asyncio yet). All three clients (Admin, Consumer, Producer) use a dedicated IO thread that drives a selector-based event loop. AdminClient/KafkaConsumer leverage a built-in io thread supplied by kafka.net, KafkaProducer continues to use its existing background Sender thread for now.

Async IO Substrate

• kafka.net: Refactored async networking modules (generator-based coroutines) (#2812)
• kafka.net: Network IO thread (#2965, #2980, #2961, #2968, #2963)
• KafkaNetClient: drop-in replacement for KafkaClient using kafka.net (#2816)
• KafkaNetSocket: interface class for socket and proxy connections (#2992)
• kafka.net.manager: Add call_soon(coro) and run(coro) for sync/async bridge (#2862)
• kafka.net.manager: Bootstrap is sync/blocking (#2919)
• connection: short-circuit send/recv when closed (#2967)
• Clamp broker_version to user-supplied api_version (#3052)

Transports and Proxies

• Default SSLContext -> PROTOCOL_TLS_CLIENT; minimum version TLS 1.2 (#2807)
• Enable TCP KeepAlive as default socket option (#2904)
• kafka.net: HTTP CONNECT proxy support (RFC 7231 s4.3.6) (#2990)

SASL Authentication

• kafka.net: Validate SASL/SCRAM iterations (#3026)
• SASL: Prefer node hostname to IP address when building mechanisms (#3003)

Timeouts and Connection Management

Per-request and per-stage timeouts replace the old single client-wide timeout.

• KIP-601: support socket_connection_setup_timeout_ms w/ exponential backoff (#3027)
• kafka.net: Bootstrap if needed for metadata refresh (#2825)
• kafka.net: Raise UnknownBrokerIdError when connection fails because node_id is not in metadata (#2876)

Futures and Wakeups

The Future primitive gains __await__ and a faster slotted implementation; cross-thread wakeups are factored out into a reusable helper.

• Future.await support (#2811)
• Future: slots and callback/errback inlining optimization (#2848)
• Future: clear callbacks/errbacks when done to avoid reference cycles (#2891)
• WakeupNotifier primitive for cross-thread/task wakeups (#2925, #2933)

Concurrency and Error Handling

Defensive checks throughout the kafka.net event loop and transport stack: improved socket I/O error handling, RuntimeErrors on misuse of the IO thread, and lock-based detection of concurrent access.

• kafka.net.selector: Break scheduled heapq ties when tasks share scheduled_at (#3007)
• kafka.net.selector: Monitor slow tasks with slow_task_threshold_secs (#2946)
• kafka.net.selector: Use threading.Lock() to detect concurrent access to poll() (#2945)
• kafka.net.selector: Track pending tasks to prevent gc before completion (#2950)
• kafka.net.selector: Support reschedule(when, task); idempotent unschedule (#2939)
• kafka.net.selector: Raise RuntimeError on concurrent access to net.poll or wakeup() (#2938)
• kafka.net.selector: Raise RuntimeError on run/call_at/call_soon_threadsafe after closed (#2971)
• kafka.net.selector: Catch unhandled exceptions in IO thread (#2970)
• kafka.net.selector: Improve error handling on sock read/write (#2995)
• kafka.net.selector: Check locks in _poll_once; add net.drain() (#2949)
• kafka.net.transport: Close connection on socket write error (#2973)

Protocol

A new JSON-schema-based dynamic protocol generator now replaces the legacy hand-written protocol classes (moved to kafka.protocol.old).

Dynamic Protocol Classes

Protocol classes are now generated from the upstream Apache Kafka JSON schemas.

• Dynamic protocol classes using upstream json schemas (#2727, #2745, #2779, #2782, #2787, #2810, #3037)
• Add .pyi type annotation stubs for generated protocol classes (#2784)
• Migrate all internal usage to new protocol classes (#2764, #2765, #2766, #2767, #2768, #2772)
• Refactor treatment of versioned ApiMessage classes (#2739)
• Lookup request header -> response class via ResponseClassRegistry (#2730)
• Manual json schema edits to restore fields dropped in Apache 4.0 (#2738)

New Types and Messages

• Add UUID protocol type (#2703)
• Add UnsignedInt16 type
• KIP-893: support nullable structs (#2889)
• Replace kafka.structs BrokerMetadata/PartitionMetadata with MetadataResponse structs (#2794)
• Add ConsumerProtocol data schemas (#2754)
• Add StickyAssignorUserData json schema (#2755)

Performance

• Protocol encode/decode optimization with inline compile/exec (#2785)
• Protocol benchmarks and profiling (make bench-protocol) (#2783)

Protocol Fixes

• Fix TaggedFields encoding/decoding (#2725, #2745, #2779)
• Fix VarInt/VarLong encoding (#2706)
• Fix CompactBytes encoding of struct data (#2782)
• Fix compiled encode_into for None arrays (#2790)
• Validate network frame size (#3019)
• Validate DataContainer version (#2759)

Helpers and Debugging

• DataContainer.to_dict() helper (#2758, #2872, #2879)
• Store in-flight request headers only for protocol parser (#2723)
• Debug log send/recv bytes from protocol parser (#2707)
• Adjust protocol debug logging; add KAFKA_PYTHON_PROTOCOL_DEBUG_LOG (#2719)
• CoordinatorType enum (GROUP/TRANSACTION/SHARE) (#3049)

Broker Version Check

Broker version inference is consolidated into a single BrokerVersionData helper that tracks the broker's reported API versions and infers a broker version string. ApiVersionsRequest is always sent on connect.

BrokerVersionData

• BrokerVersionData: consolidated version checks (#2795)
• BrokerVersionData: infer up to 4.3 (#2835, #2836, #3032)
• BrokerVersionData: support request min/max version (#2868)
• BrokerVersionData: Fix IncompatibleBrokerVersion errors; add str (#2804)

ApiVersionsRequest

• Always send ApiVersionsRequest on connect (#2802)
• Improve ApiVersionsRequest fallbacks (#2803, #2817, #2821)

Client Bootstrap

• Fix bootstrap connection error handling (#2831)
• ClusterMetadata: bootstrap_brokers(), set_topics/add_topics/metadata_request (#2805, #2792, #2796, #2797)
• Move bootstrap_brokers fallback from brokers() to least_loaded_node() (#2809)
• KafkaClient.least_loaded_node: pass bootstrap_fallback=True if needed (#2830)
• Consumer: add explicit bootstrap() method (#2975)
• Admin: explicit bootstrap on init (#2864)
• Manage metadata refresh logic in ClusterMetadata via attached manager (#2920)
• kafka.cluster: End refresh loop on close(); refresh loop catches KafkaError (#2935, #2936)
• Respect metadata backoff in KafkaNetClient (#2854)

Consumer

KafkaConsumer drops the dedicated HeartbeatThread in favor of scheduled async tasks on the kafka.net IO thread. Internals have been substantially refactored to migrate from future callbacks to async/await syntax. Feature support added for incremental cooperative rebalancing (KIP-429), rack-aware fetch (KIP-392), and log truncation detection (KIP-320/KIP-595).

Threading and IO

All consumer network I/O now flows through the shared kafka.net IO thread; consumer.poll() no longer drives the event loop directly.

• Consumer: use background thread for all network io; drop HeartbeatThread (#2965)
• Consumer: send all requests from net io thread (#2980)
• Consumer: simplify poll() with fetcher.fetch_records (#2960)
• Consumer: sleep in poll() if timeout, no records, and no fetchable partitions (#3039)
• Consumer: drop poll loop optimizations for pending offset resets and rejoins (#2959)
• Consumer: _update_fetch_positions -> _refresh_committed_offsets; dont poll in position() (#2958)
• Consumer: convert fetcher reset_offsets/send_list_offsets_requests to async def
• Consumer: use new proto attrs in Fetcher (ListOffsets/Fetch) (#2923)

Group Membership and Rebalance

• KIP-429: Incremental Cooperative Rebalance (#2999)
• KIP-429: Add on_partitions_lost rebalance listener hook (#3016)
• KIP-559: Bump JoinGroup v7 / SyncGroup v5; verify protocol_type/name (#2998)
• Rebalance Listener: raise errors, block fetches on revoked, pre-revoke unsubscribed (#3018)
• Consumer: call RebalanceListener on close (#3020)
• Preserve member id on IllegalGeneration error (#3017)

Fetch

• KIP-320: Detect and handle Log Truncation (#2978)
• KIP-392: Rack-aware fetch from closest replica (#2986, #2996)
• KIP-595: Fetch v12 support; check for log truncation and leader updates in response (#3021)
• KAFKA-7548: Retain fetched data for paused partitions (#2981)
• KAFKA-9212: Leader Epoch unreliable before Metadata v9 (#2997)

Offsets and Commits

• KIP-447: OffsetFetch v7 set require_stable flag if read_committed (#3023)
• Consumer: handle retriable errors in offsets_for_times (#3022)
• Consumer: Improve retriable offset fetch error handling (#2977)
• Consumer: Retain subscription TopicPartitionState when possible (#3001)
• Consumer: drop max_version clamp on ListOffsetsRequest (#3012)

Configuration

• KIP-602: Support client_dns_lookup in Consumer/Producer/Admin config (#3004)
• Consumer: default request_timeout_ms 30s; use request-specific timeout for JoinGroup (#3011)

Consumer Fixes

• Retry metadata request if tracked topics have retriable errors (#2832)
• Fix KeyError in KafkaConsumer.committed() (#2710)
• Fix Fetcher._fetch_offsets_by_times retry handling (#2833)

Producer

KafkaProducer gains a sticky partitioner (KIP-480), enabled-by-default idempotence (KIP-679), tightened transaction handling, and a faster send/encode path.

Transactions and Idempotence

• KIP-360 (pt1): Add transaction manager state and helper methods (#2852)
• KIP-360 (pt2): Bump producer epoch with InitProducerIdRequest v3 on 2.5+ brokers (#2853)
• KIP-447: Include group metadata in TxnOffsetCommitRequest (#2984, #2988)
• KIP-654: Txn Producer aborts with non-fatal TransactionAbortedError (#3010)
• KAFKA-5793: Tighten up semantics of OutOfOrderSequenceNumber (pt1) (#2843)
• Enable producer idempotence with max_in_flight_requests_per_connection > 1 (#2841)
• Producer: Enforce guaranteed message order when idempotence_enabled (#2937)
• Producer: treat InvalidProducerEpochError as ProducerFencedError (#2885)
• Producer: Improve transaction manager retriable error handling (#2884)
• Producer: Use new-style request construction in Txn Manager (#2983)

Partitioning

• KIP-480: StickyPartitioner for KafkaProducer (#2982, #2989)

Batching and Send Path

Split-and-resend oversized batches instead of failing; avoid redundant validation and buffer copies on hot send-path.

• KIP-126: Allow KafkaProducer to split and resend oversized batches (#2839)
• Refactor producer.send / _wait_on_metadata for fast path (#2850)
• Only ensure_valid_topic_name new topics on send (#2849)
• Avoid unnecessary bytes/bytearray copies on send (#2845)
• MemoryRecordsBuilder.build() returns bytearray buffer not bytes copy (#2842)
• Drop PartitionResponse namedtuple; consolidate response and error handling (#2851)

Producer Fixes

• Fixup Sender error class logging (#2828)

Admin Client

Split KafkaAdminClient into focused mixin classes (cluster, topics, configs, groups, ACLs, log dirs, etc), and convert request-sending path to async def methods that run on the kafka.net IO thread. Support for new KIPs using new protocol stack.

Refactor and Async Migration

The admin client interface remains sync but wraps a fully-async internal api (does not support asyncio yet). Adds cached coordinator lookups and a mixin structure to separate logical resource groups.

• Admin: split into functional mixin classes (#2873, #2877, #2882)
• Admin: convert request paths to async; cache coordinator_ids (#2851, #2862, #2863, #2866, #2867, #2870, #2871, #3050)
• Admin: refactor _send_request_to_controller error handling (#2751)

Batch Protocol Support

• KIP-699: FindCoordinatorRequest v4 -- multi-group support (#3025)
• KIP-709: OffsetFetch v8 -- use batch interface when available (#3024)

New Cluster and Quorum APIs

• Admin: describe_metadata_quorum (#2914)
• Admin: cluster features describe/update (#2908, #3053)
• Admin: cluster get_broker_version_data / api_versions (#2903)

Configs

• Admin: list_config_resources (requires 4.1+) (#2900)
• Admin: support incremental alter configs (#2901)
• Admin: Improve alter_configs w/ filters and missing keys (#2899)

Topics and Partitions

• KIP-516: Support topic id (uuid) for describe topics (#3031)
• Admin: re-use config processing for CreateTopicsResponse (#3036)
• Admin: wait_for_topics() and create_topics() wait_for_metadata option (#2856)
• Admin: list_partition_offsets (#2894)
• Admin: Expand partitions api support (#2890)
• Admin: Cleanup alter_partition_reassignments (#3002)

Groups

• Admin: include latest offsets and lag in list_group_offsets; add reset_group_offsets (#2897)
• Admin: support group state/type filters for list_groups (#2910)
• Admin: add extended group reset options (#2911)
• Admin: Dont return MemberToRemove as key in remove_group_members dict result (#2893)

Transactions

• Admin: implement KIP-664 hanging-transaction tooling (#3051)

Log Dirs

• Admin: alter_log_dirs (#2912)
• Admin: Fix describe_log_dirs, accept optional topics/brokers (#2881)

Reliability

• Admin: retry delete_records / list_partition_offsets on NotLeaderForPartitionError (#2976)

CLI

The CLI adds shared parser config, SASL/SSL connection support across all subcommands, and several new admin subcommands (acls, configs alter, users).

Common Infrastructure

• Add kafka-python cli script to wrap admin/consumer/producer (#3034)
• kafka.cli: common parser args; support sasl/ssl connections (#2887)
• kafka.cli: common configuration for logging and connect kwargs (#2906)
• Add --enable-logger/--disable-logger to cli options (#2798)
• Set default cli log level => CRITICAL (#2760)

Admin CLI

• admin cli: acls, users, configs alter (#2888)
• admin cli: refactor admin group/command parsers; consumer/producer option groups (#2909)
• admin cli: --id support for describe-topics
• admin cli: close() after running command
• admin cli: dont print stacktrace for BrokerResponseError or ValueError (#2895)
• admin cli: catch AttributeError and print_help() (#2880)
• admin cli: fix describe_configs (#2875)

Consumer CLI

• consumer cli does not require group_id (#3044)

Compatibility / Misc

Small quality-of-life additions to the public API surface.

• Support context manager interface for consumer/producer/admin (#2969)
• Make IncompatibleBrokerVersion a subclass of UnsupportedVersionError (#2924)
• Add OffsetSpec / IsolationLevel to kafka imports (#2898)
• Errors: subclasses for RetriableError and InvalidMetadataError (#3041)
• Helper classes: DefaultSerializer and JsonSerializer (#3046)

Fixes

Codec and Python-3-compatibility fixes that aren't specific to a single client.

• Fix zstd multi-frame decompression failure (#2717)
• Use time.monotonic() instead of time.time() for elapsed time calculations (#2714)
• Fix deprecated log.warn() -> log.warning()
• REF: Switch to deque.copy() for Python 3 compatibility (#2712)

Tests

A new in-memory MockBroker / MockTransport enables deterministic protocol-level tests, and the integration test fixtures have been substantially consolidated.

MockBroker and Fixtures

• MockBroker / MockTransport for deterministic protocol tests (#2861, #2902)
• Organize test files into consumer/ producer/ admin/ directories (#2844)
• Consolidate consumer integration tests (#2857)
• Consolidate more pytest fixtures (admin/client) (#2921)
• Integration fixtures use contextmanager (#2966)
• Refactor coordinator test fixtures; prefer MockBroker to patched_coord (#2953)
• Support SSL transports in KafkaFixture (#2806)
• Simplify interacting with KafkaFixture (client factories, create_topics) (#2808)
• Use producer/consumer/admin factories in producer_integration tests (#2829)
• Set api_version for integration tests; fix test_group missing consumers (#2824)
• Close local fixtures in tests (#2962)
• Catch exceptions in fixture.open() -> close() (#2907)
• Create topic on 0.8.2 broker to fix bootstrap (#2896)

Reliability

• Reduce timing flakiness in test_group (#3006)
• Test timeouts: use pytest-timeout method=thread and add faulthandler

Project Infra

• Enable pylint workflow; disable/fix all outstanding errors (#2701)
• Add coverage step to CI (#2786)
• CI test matrix updated to python 3.14 / kafka 4.3 (#2836, #3032)
• Add lint-unicode make target; include in make lint test (#2993)
• pyproject updates: no more universal wheels; requres py3.8+; fix license files; drop setup.py (#3033)
• Bump actions/cache from 4 to 5; actions/upload-artifact from 4 to 7 (#2702, #2789)

2.3.2 (Jun 3, 2026)

Fixes

• kafka.conn: Improve error handling for sasl authenticate mechanisms
• kafka.net: Validate SASL/SCRAM iterations (#3026)
• KafkaProtocol: validate network frame size (backport of #3019)
• Clear _callbacks/_errbacks list when future is_done to avoid reference cycles (#2891)

2.3.1 (Apr 9, 2026)

Fixes

• Fix TaggedFields value encoding; add test coverage (#2725)
• Fix zstd multi-frame decompression failure (#2717)
• Fix KeyError in KafkaConsumer.committed() (#2710)
• Fix VarInt/VarLong encoding; move tests to test/protocol/ (#2706)
• Fix Fetcher._fetch_offsets_by_times retry handling (#2833)
• Fixes to support integration testing with external KAFKA_URI (#2838)
• Minor py2 fixes: consumer integration test; dont pip install python-snappy

2.3.0 (Nov 20, 2025)

2.3.x will be the last release branch with python2 support!

CLI

• python -m cli interfaces for kafka.admin, kafka.consumer, kafka.producer (#2650)

Producer

• KIP-654: Abort transaction with pending data with TransactionAbortedError (#2662)
• KafkaProducer: Handle UnknownProducerIdError (#2663)
• KIP-467: Augment ProduceResponse error messaging for specific culprit records (#2661)

Consumer

• KIP-345: Consumer group static membership (#2625)
• KIP-207: Add ListOffsetsRequest v5 / handle OffsetNotAvailableError (#2657)
• Fetcher: Add missing argument in debug log (#2665)

AdminClient

• KIP-430: Return Authorized Operations in Describe Responses (#2656)
• Add send_request() and send_requests() to KafkaAdminClient (#2649)

Maintenance

• Remove old/unused kafka.protocol.pickle (#2653)
• Switch protocol code to getattr/setattr from dict (#2654)
• Drop unused imports (#2651)

Project Infra

• Bump github/codeql-action from 3 to 4 (#2678)
• Bump actions/setup-python from 5 to 6 (#2674)
• Bump actions/setup-java from 4 to 5 (#2673)
• Bump actions/checkout from 4 to 5 (#2669)
• Bump actions/checkout from 5 to 6 (#2694)
• NixOS helpers

2.2.20 (Jun 3, 2026)

Fixes

• kafka.conn: Improve error handling for sasl authenticate mechanisms
• kafka.net: Validate SASL/SCRAM iterations (#3026)
• KafkaProtocol: validate network frame size (backport of #3019)
• Clear _callbacks/_errbacks list when future is_done to avoid reference cycles (#2891)

2.2.19 (Apr 9, 2026)

Fixes

• Fix TaggedFields value encoding; add test coverage (#2725)
• Fix zstd multi-frame decompression failure (#2717)
• Fix KeyError in KafkaConsumer.committed() (#2710)
• Fix VarInt/VarLong encoding; move tests to test/protocol/ (#2706)
• Fix Fetcher._fetch_offsets_by_times retry handling (#2833)
• Fixes to support integration testing with external KAFKA_URI (#2838)
• Minor py2 fixes: consumer integration test; done pip install python-snappy

Fixes

• Add ProducerBatch.lt for heapq (#2698)

Fixes

• Add internal poll to consumer.position() (#2696)
• Initiate Coordinator Reconnect w/ Backoff from Heartbeat Thread (#2695)

Networking

• SOCKS5: support looking up names remotely (jschwartzenberg / #2666)

Documentation

• Add transactional_id to KafkaProducer Keyword Arguments docstring

Fixes

• Fix thread not waking up when there is still data to be sent (gqmelo / #2670)
• Ensure timeout is checked after each fetch position update in Consumer.position() (k61n / #2668)

2.2.15 (July 1, 2025)

Fixes

• Fix KafkaProducer broken method names (@llk89 / #2660)
• Fix spelling mistake in KafkaConsumer docs (@Xeus-CC / #2659)

2.2.14 (June 27, 2025)

Fixes

• python2 fixups (#2655)
• Fix coordinator lock contention during close() (#2652)

2.2.13 (June 20, 2025)

Fixes

• Use client.await_ready() to simplify blocking wait and add timeout to admin client (#2648)
• Fixup import style in example.py

Documentation

• update README kafka version badge to include 4.0

2.2.12 (June 18, 2025)

Fixes

• Fix construction of final GSSAPI authentication message (#2647)
• Avoid RuntimeError on mutated _completed_fetches deque in consumer fetcher (#2646)
• Throw exception on invalid bucket type (#2642)

2.2.11 (June 5, 2025)

Fixes

• Do not ignore metadata response for single topic with error (#2640)
• Fix decoding bug in AWS_MSK_IAM mechanism (#2639)
• Add synchronized decorator; add lock to subscription state (#2636)
• Update build links in documentation (#2634)

2.2.10 (May 22, 2025)

Fixes

• Set the current host in the SASL configs (#2633)
• Fix sasl gssapi plugin: do not rely on client_ctx.complete in auth_bytes() (#2631)

2.2.9 (May 21, 2025)

Fixes

• Do not reset fetch positions if offset commit fetch times out (#2629)

Logging / Error Messages

• More / updated debug logging for coordinator / consumer (#2630)

2.2.8 (May 20, 2025)

Fixes

• Wait for next heartbeat in thread loop; check for connected coordinator (#2622)
• Acquire client lock in heartbeat thread before sending requests (#2620)

Logging / Error Messages

• Log all SyncGroupResponse errors as info+
• More coordinator / heartbeat logging (#2621)
• Fix timeout seconds error message in KafkaProducer (#2627)
• Update offset commit error handling; use RebalanceInProgressError if applicable (#2623)

2.2.7 (May 13, 2025)

Fixes

• Minor Heartbeat updates: catch more exceptions / log configuration / raise KafkaConfigurationError (#2618)

2.2.6 (May 8, 2025)

Fixes

• Only disable heartbeat thread once at beginning of join-group (#2617)

2.2.5 (May 8, 2025)

Fixes

• Fix producer busy loop with no pending batches (#2616)
• Fixup py27 fetcher test failure

2.2.4 (May 3, 2025)

Fixes

• Do not reset_generation after RebalanceInProgressError; improve CommitFailed error messages (#2614)
• Fix KafkaConsumer.poll() with zero timeout (#2613)
• Fix Fetch._reset_offsets_async() KeyError when fetching from multiple nodes (#2612)

2.2.3 (May 1, 2025)

Fixes

• Ignore leading SECURITY_PROTOCOL:// in bootstrap_servers (#2608)
• Only create fetch requests for ready nodes (#2607)

2.2.2 (Apr 30, 2025)

Fixes

• Fix lint errors

2.2.1 (Apr 29, 2025)

Fixes

• Always try ApiVersionsRequest v0, even on broker disconnect (#2603)
• Fix SubscriptionState AttributeError in KafkaConsumer (#2599)

Documentation

• Add transactional examples to docs

2.2.0 (Apr 28, 2025)

KafkaProducer

• KIP-98: Add idempotent producer support (#2569)
• KIP-98: Transactional Producer (#2587)
• KIP-98: Add offsets support to transactional KafkaProducer (#2590)
• Prefix producer logs w/ client id and transactional id (#2591)
• KAFKA-5429: Ignore produce response if batch was previously aborted
• KIP-91: KafkaProducer delivery_timeout_ms
• Default retries -> infinite
• Expand KafkaProducer docstring w/ idempotent and transactional notes
• RecordAccumulator: Use helper method to get/set _tp_locks; get dq with lock in reenqueue()

KafkaConsumer

• KIP-98: Add Consumer support for READ_COMMITTED (#2582)
• KIP-394: handle MEMBER_ID_REQUIRED error w/ second join group request (#2598)
• KAFKA-5078: Defer fetch record exception if iterator has already moved across a valid record
• KAFKA-5075: Defer consumer fetcher exception if fetch position has already increased
• KAFKA-4937: Batch offset fetches in the Consumer
• KAFKA-4547: Avoid resetting paused partitions to committed offsets
• KAFKA-6397: Consumer should not block setting positions of unavailable partitions (#2593)

Potentially Breaking Changes (internal)

• Rename CorruptRecordException -> CorruptRecordError
• Rename Coordinator errors to generic not group (#2585)
• Rename ClusterMetadata.add_group_coordinator -> add_coordinator + support txn type
• Use SaslAuthenticationFailedError in kafka.conn connection failure; Drop unused AuthenticationFailedError
• Remove old/unused errors; reorder; KafkaTimeout -> retriable
• Drop log_start_offset from producer RecordMetadata

Internal

• MemoryRecords iterator; MemoryRecordsBuilder records() helper
• Convert DefaultRecordsBuilder.size_in_bytes to classmethod

Fixes

• Resolve datetime deprecation warnings (#2589)
• Avoid self refcount in log messages; test thread close on all pythons
• Fix client.wakeup() race from producer/sender close
• Fix ElectionNotNeededError handling in admin client

Tests

• Move integration tests and fixtures to test/integration/; simplify unit fixtures (#2588)
• Expand Sender test coverage (#2586)
• py2 test fixups
• Drop unused KafkaClient import from test_fetcher

2.1.6 (May 2, 2025)

Fixes

• Only create fetch requests for ready nodes (#2607)

2.1.5 (Apr 4, 2025)

Fixes

• Fix python2.7 errors (#2578)

Improvements

• Move benchmark scripts to kafka.benchmarks module (#2584)
• Use __slots__ for metrics (#2583)
• Pass metrics_enabled=False to disable metrics (#2581)
• Drop unused kafka.producer.buffer / SimpleBufferPool (#2580)
• Raise UnsupportedVersionError from coordinator (#2579)

2.1.4 (Mar 28, 2025)

Fixes

• Dont block pending FetchRequests when Metadata update requested (#2576)
• Fix MetadataRequest for no topics (#2573)
• Send final error byte x01 on Sasl OAuth failure (#2572)
• Reset SASL state on disconnect (#2571)
• Try import new Sequence before old to avoid DeprecationWarning

Improvements

• Update Makefile default to 4.0 broker; add make fixture
• Improve connection state logging (#2574)

2.1.3 (Mar 25, 2025)

Fixes

• Fix crash when switching to closest compatible api_version in KafkaClient (#2567)
• Fix maximum version to send an OffsetFetchRequest in KafkaAdminClient (#2563)
• Return empty set from consumer.partitions_for_topic when topic not found (#2556)

Improvements

• KIP-511: Use ApiVersions v4 on initial connect w/ client_software_name + version (#2558)
• KIP-74: Manage assigned partition order in consumer (#2562)
• KIP-70: Auto-commit offsets on consumer.unsubscribe(), defer assignment changes to rejoin (#2560)
• Use SubscriptionType to track topics/pattern/user assignment (#2565)
• Add optional timeout_ms kwarg to consumer.close() (#2564)
• Move ensure_valid_topic_name to kafka.util; use in client and producer (#2561)

Testing

• Support KRaft / 4.0 brokers in tests (#2559)
• Test older pythons against 4.0 broker

Compatibility

• Add python 3.13 to compatibility list

2.1.2 (Mar 17, 2025)

Fixes

• Simplify consumer.poll send fetches logic
• Fix crc validation in consumer / fetcher
• Lazy _unpack_records in PartitionRecords to fix premature fetch offset advance in consumer.poll() (#2555)
• Debug log fetch records return; separate offsets update log
• Fix Fetcher retriable error handling (#2554)
• Use six.add_metaclass for py2/py3 compatible abc (#2551)

Improvements

• Add FetchMetrics class; move topic_fetch_metrics inside aggregator
• DefaultRecordsBatchBuilder: support empty batch
• MemoryRecordsBuilder: support arbitrary offset, skipping offsets
• Add record.validate_crc() for v0/v1 crc checks
• Remove fetcher message_generator / iterator interface
• Add size_in_bytes to ABCRecordBatch and implement for Legacy and Default
• Add magic property to ABCRecord and implement for LegacyRecord

2.1.1 (Mar 16, 2025)

Fixes

• Fix packaging of 2.1.0 in Fedora: testing requires "pytest-timeout". (#2550)
• Improve connection error handling when try_api_versions_check fails all attempts (#2548)
• Add lock synchronization to Future success/failure (#2549)
• Fix StickyPartitionAssignor encode

2.1.0 (Mar 15, 2025)

Support Kafka Broker 2.1 API Baseline

• Add baseline leader_epoch support for ListOffsets v4 / FetchRequest v10 (#2511)
• Support OffsetFetch v5 / OffsetCommit v6 (2.1 baseline) (#2505)
• Support 2.1 baseline consumer group apis (#2503)
• Support FindCoordinatorRequest v2 in consumer and admin client (#2502)
• Support ListOffsets v3 in consumer (#2501)
• Support Fetch Request/Response v6 in consumer (#2500)
• Add support for Metadata Request/Response v7 (#2497)
• Implement Incremental Fetch Sessions / KIP-227 (#2508)
• Implement client-side connection throttling / KIP-219 (#2510)
• Add KafkaClient.api_version(operation) for best available from api_versions (#2495)

Consumer

• Timeout coordinator poll / ensure_coordinator_ready / ensure_active_group (#2526)
• Add optional timeout_ms kwarg to remaining consumer/coordinator methods (#2544)
• Check for coordinator.poll failure in KafkaConsumer
• Only mark coordinator dead if connection_delay > 0 (#2530)
• Delay group coordinator until after bootstrap (#2539)
• KAFKA-4160: Ensure rebalance listener not called with coordinator lock (#1438)
• Call default_offset_commit_callback after _maybe_auto_commit_offsets_async (#2546)
• Remove legacy/v1 consumer message iterator (#2543)
• Log warning when attempting to list offsets for unknown topic/partition (#2540)
• Add heartbeat thread id to debug logs on start
• Add inner_timeout_ms handler to fetcher; add fallback (#2529)

Producer

• KafkaProducer: Flush pending records before close() (#2537)
• Raise immediate error on producer.send after close (#2542)
• Limit producer close timeout to 1sec in del; use context managers to close in test_producer
• Use NullLogger in producer atexit cleanup
• Attempt to fix metadata race condition when partitioning in producer.send (#2523)
• Remove unused partial KIP-467 implementation (ProduceResponse batch error details) (#2524)

AdminClient

• Implement perform leader election (#2536)
• Support delete_records (#2535)

Networking

• Call ApiVersionsRequest during connection, prior to Sasl Handshake (#2493)
• Fake api_versions for old brokers, rename to ApiVersionsRequest, and handle error decoding (#2494)
• Debug log when skipping api_versions request with pre-configured api_version
• Only refresh metadata if connection fails all dns records (#2532)
• Support connections through SOCKS5 proxies (#2531)
• Fix OverflowError when connection_max_idle_ms is 0 or inf (#2538)
• socket.setblocking for eventlet/gevent compatibility
• Support custom per-request timeouts (#2498)
• Include request_timeout_ms in request debug log
• Support client.poll with future and timeout_ms
• mask unused afi var
• Debug log if check_version connection attempt fails

SASL Modules

• Refactor Sasl authentication with SaslMechanism abstract base class; support SaslAuthenticate (#2515)
• Add SSPI (Kerberos for Windows) authentication mechanism (#2521)
• Support AWS_MSK_IAM authentication (#2519)
• Cleanup sasl mechanism configuration checks; fix gssapi bugs; add sasl_kerberos_name config (#2520)
• Move kafka.oauth.AbstractTokenProvider -> kafka.sasl.oauth.AbstractTokenProvider (#2525)

Testing

• Bump default python to 3.13 in CI tests (#2541)
• Update pytest log_format: use logger instead of filename; add thread id
• Improve test_consumer_group::test_group logging before group stabilized (#2534)
• Limit test duration to 5mins w/ pytest-timeout
• Fix external kafka/zk fixtures for testing (#2533)
• Disable zookeeper admin server to avoid port conflicts
• Set default pytest log level to debug
• test_group: shorter timeout, more logging, more sleep
• Cache servers/dist in github actions workflow (#2527)
• Remove tox.ini; update testing docs
• Use thread-specific client_id in test_group
• Fix subprocess log warning; specify timeout_ms kwarg in consumer.poll tests
• Only set KAFKA_JVM_PERFORMANCE_OPTS in makefile if unset; add note re: 2.0-2.3 broker testing
• Add kafka command to test.fixtures; raise FileNotFoundError if version not installed

Documentation

• Improve ClusterMetadata docs re: node_id/broker_id str/int types
• Document api_version_auto_timeout_ms default; override in group tests

Fixes

• Signal close to metrics expire_loop
• Add kafka.util timeout_ms_fn
• fixup TopicAuthorizationFailedError construction
• Fix lint issues via ruff check (#2522)
• Make the "mock" dependency optional (only used in Python < 3.3). (#2518)

2.0.6 (Mar 4, 2025)

Networking

• Improve error handling in client._maybe_connect (#2504)
• Client connection / maybe_refresh_metadata changes (#2507)
• Improve too-large timeout handling in client poll
• Default client.check_version timeout to api_version_auto_timeout_ms (#2496)

Fixes

• Decode and skip transactional control records in consumer (#2499)
• try / except in consumer coordinator __del__

Testing

• test_conn fixup for py2

Project Maintenance

• Add 2.0 branch for backports

2.0.5 (Feb 25, 2025)

Networking

• Remove unused client bootstrap backoff code
• 200ms timeout for client.poll in ensure_active_group and admin client

Fixes

• Admin client: check_version only if needed, use node_id kwarg for controller
• Check for -1 controller_id in admin client
• Only acquire coordinator lock in heartbeat thread close if not self thread

Testing

• Also sleep when waiting for consumers in test_describe_consumer_group_exists
• Refactor sasl_integration test_client - wait for node ready; use send future
• Add timeout to test_kafka_consumer
• Add error str to assert_message_count checks
• Retry on error in test fixture create_topic_via_metadata
• Fixup variable interpolation in test fixture error

Documentation

• Update compatibility docs
• Include client_id in BrokerConnection str output

Project Maintenance

• Add make targets servers/*/api_versions and servers/*/messages

2.0.4 (Feb 21, 2025)

Networking

• Check for wakeup socket errors on read and close and reinit to reset (#2482)
• Improve client networking backoff / retry (#2480)
• Check for socket and unresolved futures before creating selector in conn.check_version (#2477)
• Handle socket init errors, e.g., when IPv6 is disabled (#2476)

Fixes

• Avoid self-join in heartbeat thread close (#2488)

Error Handling

• Always log broker errors in producer.send (#2478)
• Retain unrecognized broker response error codes with dynamic error class (#2481)
• Update kafka.errors with latest types (#2485)

Compatibility

• Do not validate snappy xerial header version and compat fields (for redpanda) (#2483)

Documentation

• Added missing docstrings in admin/client.py (#2487)

Testing

• Update kafka broker test matrix; test against 3.9.0 (#2486)
• Add default resources for new kafka server fixtures (#2484)
• Drop make test-local; add PYTESTS configuration var
• Fix pytest runs when KAFKA_VERSION is not set

Project Maintenance

• Migrate to pyproject.toml / PEP-621
• Remove old travis files; update compatibility tests link to gha

2.0.3 (Feb 12, 2025)

Improvements

• Add optional compression libs to extras_require (#2123, #2387)
• KafkaConsumer: Exit poll if consumer is closed (#2152)
• Support configuration of custom kafka client for Admin/Consumer/Producer (#2144)
• Core Protocol: Add support for flexible versions (#2151)
• (Internal) Allow disabling thread wakeup in _send_request_to_node (#2335)
• Change loglevel of cancelled errors to info (#2467)
• Strip trailing dot off hostname for SSL validation. (#2472)
• Log connection close(error) at ERROR level (#2473)
• Support DescribeLogDirs admin api (#2475)

Compatibility

• Support for python 3.12 (#2379, #2382)
• Kafka 2.5 / 2.6 (#2162)
• Try collections.abc imports in vendored selectors34 (#2394)
• Catch OSError when checking for gssapi import for windows compatibility (#2407)
• Update vendored six to 1.16.0 (#2398)

Documentation

• Update usage.rst (#2308, #2334)
• Fix typos (#2319, #2207, #2178)
• Fix links to the compatibility page (#2295, #2226)
• Cleanup install instructions for optional libs (#2139)
• Update license_file to license_files (#2462)
• Update some RST documentation syntax (#2463)
• Add .readthedocs.yaml; update copyright date (#2474)

Fixes

• Use isinstance in builtin crc32 (#2329)
• Use six.viewitems instead of six.iteritems to avoid encoding problems in StickyPartitionAssignor (#2154)
• Fix array encoding TypeError: object of type 'dict_itemiterator' has no len() (#2167)
• Only try to update sensors fetch lag if the unpacked list contains elements (#2158)
• Avoid logging errors during test fixture cleanup (#2458)
• Release coordinator lock before calling maybe_leave_group (#2460)
• Dont raise RuntimeError for dead process in SpawnedService.wait_for() (#2461)
• Cast the size of a MemoryRecordsBuilder object (#2438)
• Fix DescribeConfigsResponse_v1 config_source (#2464)
• Fix base class of DescribeClientQuotasResponse_v0 (#2465)
• Update socketpair w/ CVE-2024-3219 fix (#2468)

Testing

• Transition CI/CD to GitHub Workflows (#2378, #2392, #2381, #2406, #2419, #2418, #2417, #2456)
• Refactor Makefile (#2457)
• Use assert_called_with in client_async tests (#2375)
• Cover sticky assignor's metadata method with tests (#2161)
• Update fixtures.py to check "127.0.0.1" for auto port assignment (#2384)
• Use -Djava.security.manager=allow for Java 23 sasl tests (#2469)
• Test with Java 23 (#2470)
• Update kafka properties template; disable group rebalance delay (#2471)

2.0.2 (Sep 29, 2020)

Consumer

• KIP-54: Implement sticky partition assignment strategy (aynroot / PR #2057)
• Fix consumer deadlock when heartbeat thread request timeout (huangcuiyang / PR #2064)

Compatibility

• Python 3.8 support (Photonios / PR #2088)

Cleanups

• Bump dev requirements (jeffwidman / PR #2129)
• Fix crc32c deprecation warning (crc32c==2.1) (jeffwidman / PR #2128)
• Lint cleanup (jeffwidman / PR #2126)
• Fix initialization order in KafkaClient (pecalleja / PR #2119)
• Allow installing crc32c via extras (mishas / PR #2069)
• Remove unused imports (jameslamb / PR #2046)

Admin Client

• Merge _find_coordinator_id methods (jeffwidman / PR #2127)
• Feature: delete consumergroups (swenzel / PR #2040)
• Allow configurable timeouts in admin client check version (sunnyakaxd / PR #2107)
• Enhancement for Kafka Admin Client's "Describe Consumer Group" (Apurva007 / PR #2035)

Protocol

• Add support for zstd compression (gabriel-tincu / PR #2021)
• Add protocol support for brokers 1.1.0 - 2.5.0 (gabriel-tincu / PR #2038)
• Add ProduceRequest/ProduceResponse v6/v7/v8 (gabriel-tincu / PR #2020)
• Fix parsing NULL header values (kvfi / PR #2024)

Tests

• Add 2.5.0 to automated CI tests (gabriel-tincu / PR #2038)
• Add 2.1.1 to build_integration (gabriel-tincu / PR #2019)

Documentation / Logging / Errors

• Disable logging during producer object gc (gioele / PR #2043)
• Update example.py; use threading instead of multiprocessing (Mostafa-Elmenbawy / PR #2081)
• Fix typo in exception message (haracejacob / PR #2096)
• Add kafka.structs docstrings (Mostafa-Elmenbawy / PR #2080)
• Fix broken compatibility page link (anuragrana / PR #2045)
• Rename README to README.md (qhzxc0015 / PR #2055)
• Fix docs by adding SASL mention (jeffwidman / #1990)

2.0.1 (Feb 19, 2020)

Admin Client

• KAFKA-8962: Use least_loaded_node() for AdminClient.describe_topics() (jeffwidman / PR #2000)
• Fix AdminClient topic error parsing in MetadataResponse (jtribble / PR #1997)

2.0.0 (Feb 10, 2020)

This release includes breaking changes for any application code that has not migrated from older Simple-style classes to newer Kafka-style classes.

Deprecation

• Remove deprecated SimpleClient, Producer, Consumer, Unittest (jeffwidman / PR #1196)

Admin Client

• Use the controller for topic metadata requests (TylerLubeck / PR #1995)
• Implement list_topics, describe_topics, and describe_cluster (TylerLubeck / PR #1993)
• Implement eq and hash for ACL objects (TylerLubeck / PR #1955)
• Fixes KafkaAdminClient returning IncompatibleBrokerVersion when passing an api_version (ian28223 / PR #1953)
• Admin protocol updates (TylerLubeck / PR #1948)
• Fix describe config for multi-broker clusters (jlandersen / PR #1869)

Miscellaneous Bugfixes / Improvements

• Enable SCRAM-SHA-256 and SCRAM-SHA-512 for sasl (swenzel / PR #1918)
• Fix slots usage and use more slots (carsonip / PR #1987)
• Optionally return OffsetAndMetadata from consumer.committed(tp) (dpkp / PR #1979)
• Reset conn configs on exception in conn.check_version() (dpkp / PR #1977)
• Do not block on sender thread join after timeout in producer.close() (dpkp / PR #1974)
• Implement methods to convert a Struct object to a pythonic object (TylerLubeck / PR #1951)

Test Infrastructure / Documentation / Maintenance

• Update 2.4.0 resource files for sasl integration (dpkp)
• Add kafka 2.4.0 to CI testing (vvuibert / PR #1972)
• convert test_admin_integration to pytest (ulrikjohansson / PR #1923)
• xfail test_describe_configs_topic_resource_returns_configs (dpkp / Issue #1929)
• Add crc32c to README and docs (dpkp)
• Improve docs for reconnect_backoff_max_ms (dpkp / PR #1976)
• Fix simple typo: managementment -> management (timgates42 / PR #1966)
• Fix typos (carsonip / PR #1938)
• Fix doc import paths (jeffwidman / PR #1933)
• Update docstring to match conn.py's (dabcoder / PR #1921)
• Do not log topic-specific errors in full metadata fetch (dpkp / PR #1980)
• Raise AssertionError if consumer closed in poll() (dpkp / PR #1978)
• Log retriable coordinator NodeNotReady, TooManyInFlightRequests as debug not error (dpkp / PR #1975)
• Remove unused import (jeffwidman)
• Remove some dead code (jeffwidman)
• Fix a benchmark to Use print() function in both Python 2 and Python 3 (cclauss / PR #1983)
• Fix a test to use ==/!= to compare str, bytes, and int literals (cclauss / PR #1984)
• Fix benchmarks to use pyperf (carsonip / PR #1986)
• Remove unused/empty .gitsubmodules file (jeffwidman / PR #1928)
• Remove deprecated ConnectionError (jeffwidman / PR #1816)

1.4.7 (Sep 30, 2019)

This release is focused on KafkaConsumer performance, Admin Client improvements, and Client concurrency. The KafkaConsumer iterator implementation has been greatly simplified so that it just wraps consumer.poll(). The prior implementation will remain available for a few more releases using the optional KafkaConsumer config: legacy_iterator=True . This is expected to improve consumer throughput substantially and help reduce heartbeat failures / group rebalancing.

Major thanks to @carsonip @Baisang @iv-m @davidheitman @cardy31 @ulrikjohansson @iAnomaly @Wayde2014 @ossdev07 @commanderdishwasher @justecorruptio @melor @rustyrothwurt @sachiin @jacky15 and @rikonen for submitting PRs; thanks as well to everyone that submitted bug reports and issues, and to @jeffwidman and @tvoinarovskyi for code reviews, comments, testing, debugging, and helping to maintain kafka-python!

Client

• Send socket data via non-blocking IO with send buffer (@dpkp / PR #1912)
• Rely on socket selector to detect completed connection attempts (@dpkp / PR #1909)
• Improve connection lock handling; always use context manager (@melor @dpkp / PR #1895)
• Reduce client poll timeout when there are no in-flight requests (@dpkp / PR #1823)

KafkaConsumer

• Do not use wakeup when sending fetch requests from consumer (@dpkp / PR #1911)
• Wrap consumer.poll() for KafkaConsumer iteration (@dpkp / PR #1902)
• Allow the coordinator to auto-commit on old brokers (@justecorruptio / PR #1832)
• Reduce internal client poll timeout for (legacy) consumer iterator interface (@dpkp / PR #1824)
• Use dedicated connection for group coordinator (@dpkp / PR #1822)
• Change coordinator lock acquisition order (@dpkp / PR #1821)
• Make partitions_for_topic a read-through cache (@Baisang / PR #1781,#1809)
• Fix consumer hanging indefinitely on topic deletion while rebalancing (@commanderdishwasher / PR #1782)

Miscellaneous Bugfixes / Improvements

• Fix crc32c avilability on non-intel architectures (@ossdev07 / PR #1904)
• Load system default SSL CAs if ssl_cafile is not provided (@iAnomaly / PR #1883)
• Catch py3 TimeoutError in BrokerConnection send/recv (@dpkp / PR #1820)
• Added a function to determine if bootstrap is successfully connected (@Wayde2014 / PR #1876)

Admin Client

• Add ACL api support to KafkaAdminClient (@ulrikjohansson / PR #1833)
• Add sasl_kerberos_domain_name config to KafkaAdminClient (@jeffwidman / PR #1852)
• Update security_protocol config documentation for KafkaAdminClient (@cardy31 / PR #1849)
• Break FindCoordinator into request/response methods in KafkaAdminClient (@jeffwidman / PR #1871)
• Break consumer operations into request / response methods in KafkaAdminClient (@jeffwidman / PR #1845)
• Parallelize calls to _send_request_to_node() in KafkaAdminClient (@davidheitman / PR #1807)

Test Infrastructure / Documentation / Maintenance

• Add Kafka 2.3.0 to test matrix and compatibility docs (dpkp / PR #1915)
• Convert remaining KafkaConsumer tests to pytest (@jeffwidman / PR #1886)
• Bump integration tests to 0.10.2.2 and 0.11.0.3 (@jeffwidman / #1890)
• Cleanup handling of KAFKA_VERSION env var in tests (@jeffwidman / PR #1887)
• Minor test cleanup (@jeffwidman / PR #1885)
• Use socket.SOCK_STREAM in test assertions (@iv-m / PR #1879)
• Sanity test for consumer.topics() and consumer.partitions_for_topic() (@Baisang / PR #1829)
• Cleanup seconds conversion in client poll timeout calculation (@jeffwidman / PR #1825)
• Remove unused imports (@jeffwidman / PR #1808)
• Cleanup python nits in RangePartitionAssignor (@jeffwidman / PR #1805)
• Update links to kafka consumer config docs (@jeffwidman)
• Fix minor documentation typos (@carsonip / PR #1865)
• Remove unused/weird comment line (@jeffwidman / PR #1813)
• Update docs for api_version_auto_timeout_ms (@jeffwidman / PR #1812)

1.4.6 (Apr 2, 2019)

This is a patch release primarily focused on bugs related to concurrency, SSL connections and testing, and SASL authentication. Major thanks to @pt2pham , @isamaru , @braedon , @gingercookiemage , for submitting PRs to help fix many of these issues. And major thanks to everyone that submitted bug reports and issues. And thanks always to @jeffwidman and @tvoinarovskyi for code reviews, comments, testing, debugging, and helping to maintain this project!

Client Concurrency Issues (Race Conditions / Deadlocks)

• Fix race condition in protocol.send_bytes (isamaru / PR #1752)
• Do not call state_change_callback with lock (dpkp / PR #1775)
• Additional BrokerConnection locks to synchronize protocol/IFR state (dpkp / PR #1768)
• Send pending requests before waiting for responses (dpkp / PR #1762)
• Avoid race condition on client._conns in send() (dpkp / PR #1772)
• Hold lock during client.check_version (dpkp / PR #1771)

Producer Wakeup / TimeoutError

• Dont wakeup during maybe_refresh_metadata -- it is only called by poll() (dpkp / PR #1769)
• Dont do client wakeup when sending from sender thread (dpkp / PR #1761)

SSL - Python3.7 Support / Bootstrap Hostname Verification / Testing

• Wrap SSL sockets after connecting for python3.7 compatibility (dpkp / PR #1754)
• Allow configuration of SSL Ciphers (dpkp / PR #1755)
• Maintain shadow cluster metadata for bootstrapping (dpkp / PR #1753)
• Generate SSL certificates for local testing (dpkp / PR #1756)
• Rename ssl.keystore.location and ssl.truststore.location config files (dpkp)
• Reset reconnect backoff on SSL connection (dpkp / PR #1777)

SASL - OAuthBearer support / api version bugfix

• Fix 0.8.2 protocol quick detection / fix SASL version check (dpkp / PR #1763)
• Update sasl configuration docstrings to include supported mechanisms (dpkp)
• Support SASL OAuthBearer Authentication (pt2pham / PR #1750)

Miscellaneous Bugfixes

• Dont force metadata refresh when closing unneeded bootstrap connections (dpkp / PR #1773)
• Fix possible AttributeError during conn._close_socket (dpkp / PR #1776)
• Return connection state explicitly after close in connect() (dpkp / PR #1778)
• Fix flaky conn tests that use time.time (dpkp / PR #1758)
• Add py to requirements-dev (dpkp)
• Fixups to benchmark scripts for py3 / new KafkaFixture interface (dpkp)

1.4.5 (Mar 14, 2019)

This release is primarily focused on addressing lock contention and other coordination issues between the KafkaConsumer and the background heartbeat thread that was introduced in the 1.4 release.

Consumer

• connections_max_idle_ms must be larger than request_timeout_ms (jeffwidman / PR #1688)
• Avoid race condition during close() / join heartbeat thread (dpkp / PR #1735)
• Use last offset from fetch v4 if available to avoid getting stuck in compacted topic (keithks / PR #1724)
• Synchronize puts to KafkaConsumer protocol buffer during async sends (dpkp / PR #1733)
• Improve KafkaConsumer join group / only enable Heartbeat Thread during stable group (dpkp / PR #1695)
• Remove unused skip_double_compressed_messages (jeffwidman / PR #1677)
• Fix commit_offsets_async() callback (Faqa / PR #1712)

Client

• Retry bootstrapping after backoff when necessary (dpkp / PR #1736)
• Recheck connecting nodes sooner when refreshing metadata (dpkp / PR #1737)
• Avoid probing broker versions twice on newer brokers (dpkp / PR #1738)
• Move all network connections and writes to KafkaClient.poll() (dpkp / PR #1729)
• Do not require client lock for read-only operations (dpkp / PR #1730)
• Timeout all unconnected conns (incl SSL) after request_timeout_ms (dpkp / PR #1696)

Admin Client

• Fix AttributeError in response topic error codes checking (jeffwidman)
• Fix response error checking in KafkaAdminClient send_to_controller (jeffwidman)
• Fix NotControllerError check (jeffwidman)

Core/Protocol

• Fix default protocol parser version / 0.8.2 version probe (dpkp / PR #1740)
• Make NotEnoughReplicasError/NotEnoughReplicasAfterAppendError retriable (le-linh / PR #1722)

Bugfixes

• Use copy() in metrics() to avoid thread safety issues (emeric254 / PR #1682)

Test Infrastructure

• Mock dns lookups in test_conn (dpkp / PR #1739)
• Use test.fixtures.version not test.conftest.version to avoid warnings (dpkp / PR #1731)
• Fix test_legacy_correct_metadata_response on x86 arch (stanislavlevin / PR #1718)
• Travis CI: 'sudo' tag is now deprecated in Travis (cclauss / PR #1698)
• Use Popen.communicate() instead of Popen.wait() (Baisang / PR #1689)

Compatibility

• Catch thrown OSError by python 3.7 when creating a connection (danjo133 / PR #1694)
• Update travis test coverage: 2.7, 3.4, 3.7, pypy2.7 (jeffwidman, dpkp / PR #1614)
• Drop dependency on sphinxcontrib-napoleon (stanislavlevin / PR #1715)
• Remove unused import from kafka/producer/record_accumulator.py (jeffwidman / PR #1705)
• Fix SSL connection testing in Python 3.7 (seanthegeek, silentben / PR #1669)

Bugfixes

• (Attempt to) Fix deadlock between consumer and heartbeat (zhgjun / dpkp #1628)
• Fix Metrics dict memory leak (kishorenc #1569)

Client

• Support Kafka record headers (hnousiainen #1574)
• Set socket timeout for the write-side of wake socketpair (Fleurer #1577)
• Add kerberos domain name config for gssapi sasl mechanism handshake (the-sea #1542)
• Support smaller topic metadata fetch during bootstrap (andyxning #1541)
• Use TypeError for invalid timeout type (jeffwidman #1636)
• Break poll if closed (dpkp)

Admin Client

• Add KafkaAdminClient class (llamahunter #1540)
• Fix list_consumer_groups() to query all brokers (jeffwidman #1635)
• Stop using broker-errors for client-side problems (jeffwidman #1639)
• Fix send to controller (jeffwidman #1640)
• Add group coordinator lookup (jeffwidman #1641)
• Fix describe_groups (jeffwidman #1642)
• Add list_consumer_group_offsets() (jeffwidman #1643)
• Remove support for api versions as strings from KafkaAdminClient (jeffwidman #1644)
• Set a clear default value for validate_only/include_synonyms (jeffwidman #1645)
• Bugfix: Always set this_groups_coordinator_id (jeffwidman #1650)

Consumer

• Fix linter warning on import of ConsumerRebalanceListener (ben-harack #1591)
• Remove ConsumerTimeout (emord #1587)
• Return future from commit_offsets_async() (ekimekim #1560)

Core / Protocol

• Add protocol structs for {Describe,Create,Delete} Acls (ulrikjohansson #1646/partial)
• Pre-compile pack/unpack function calls (billyevans / jeffwidman #1619)
• Don't use kafka.common internally (jeffwidman #1509)
• Be explicit with tuples for %s formatting (jeffwidman #1634)

Documentation

• Document connections_max_idle_ms (jeffwidman #1531)
• Fix sphinx url (jeffwidman #1610)
• Update remote urls: snappy, https, etc (jeffwidman #1603)
• Minor cleanup of testing doc (jeffwidman #1613)
• Various docstring / pep8 / code hygiene cleanups (jeffwidman #1647)

Test Infrastructure

• Stop pinning pylint (jeffwidman #1611)
• (partial) Migrate from Unittest to pytest (jeffwidman #1620)
• Minor aesthetic cleanup of partitioner tests (jeffwidman #1618)
• Cleanup fixture imports (jeffwidman #1616)
• Fix typo in test file name (jeffwidman)
• Remove unused ivy_root variable (jeffwidman)
• Add test fixtures for kafka versions 1.0.2 -> 2.0.1 (dpkp)
• Bump travis test for 1.x brokers to 1.1.1 (dpkp)

Logging / Error Messages

• raising logging level on messages signalling data loss (sibiryakov #1553)
• Stop using deprecated log.warn() (jeffwidman #1615)
• Fix typo in logging message (jeffwidman)

Compatibility

• Vendor enum34 (jeffwidman #1604)
• Bump vendored six to 1.11.0 (jeffwidman #1602)
• Vendor six consistently (jeffwidman #1605)
• Prevent pylint import errors on six.moves (jeffwidman #1609)

Compatibility

• Fix for python 3.7 support: remove 'async' keyword from SimpleProducer (dpkp #1454)

Client

• Improve BrokerConnection initialization time (romulorosa #1475)
• Ignore MetadataResponses with empty broker list (dpkp #1506)
• Improve connection handling when bootstrap list is invalid (dpkp #1507)

Consumer

• Check for immediate failure when looking up coordinator in heartbeat thread (dpkp #1457)

Core / Protocol

• Always acquire client lock before coordinator lock to avoid deadlocks (dpkp #1464)
• Added AlterConfigs and DescribeConfigs apis (StephenSorriaux #1472)
• Fix CreatePartitionsRequest_v0 (StephenSorriaux #1469)
• Add codec validators to record parser and builder for all formats (tvoinarovskyi #1447)
• Fix MemoryRecord bugs re error handling and add test coverage (tvoinarovskyi #1448)
• Force lz4 to disable Kafka-unsupported block linking when encoding (mnito #1476)
• Stop shadowing ConnectionError (jeffwidman #1492)

Documentation

• Document methods that return None (jeffwidman #1504)
• Minor doc capitalization cleanup (jeffwidman)
• Adds add_callback/add_errback example to docs (Berkodev #1441)
• Fix KafkaConsumer docstring for request_timeout_ms default (dpkp #1459)

Test Infrastructure

• Skip flakey SimpleProducer test (dpkp)
• Fix skipped integration tests if KAFKA_VERSION unset (dpkp #1453)

Logging / Error Messages

• Stop using deprecated log.warn() (jeffwidman)
• Change levels for some heartbeat thread logging (dpkp #1456)
• Log Heartbeat thread start / close for debugging (dpkp)

Bugfixes

• Close leaked selector in version check (dpkp #1425)
• Fix BrokerConnection.connection_delay() to return milliseconds (dpkp #1414)
• Use local copies in Fetcher._fetchable_partitions to avoid mutation errors (dpkp #1400)
• Fix error var name in _unpack (j2gg0s #1403)
• Fix KafkaConsumer compacted offset handling (dpkp #1397)
• Fix byte size estimation with kafka producer (blakeembrey #1393)
• Fix coordinator timeout in consumer poll interface (braedon #1384)

Client

• Add BrokerConnection.connect_blocking() to improve bootstrap to multi-address hostnames (dpkp #1411)
• Short-circuit BrokerConnection.close() if already disconnected (dpkp #1424)
• Only increase reconnect backoff if all addrinfos have been tried (dpkp #1423)
• Make BrokerConnection .host / .port / .afi immutable to avoid incorrect 'metadata changed' checks (dpkp #1422)
• Connect with sockaddrs to support non-zero ipv6 scope ids (dpkp #1433)
• Check timeout type in KafkaClient constructor (asdaraujo #1293)
• Update string representation of SimpleClient (asdaraujo #1293)
• Do not validate api_version against known versions (dpkp #1434)

Consumer

• Avoid tight poll loop in consumer when brokers are down (dpkp #1415)
• Validate max_records in KafkaConsumer.poll (dpkp #1398)
• KAFKA-5512: Awake heartbeat thread when it is time to poll (dpkp #1439)

Producer

• Validate that serializers generate bytes-like (or None) data (dpkp #1420)

Core / Protocol

• Support alternative lz4 package: lz4framed (everpcpc #1395)
• Use hardware accelerated CRC32C function if available (tvoinarovskyi #1389)
• Add Admin CreatePartitions API call (alexef #1386)

Test Infrastructure

• Close KafkaConsumer instances during tests (dpkp #1410)
• Introduce new fixtures to prepare for migration to pytest (asdaraujo #1293)
• Removed pytest-catchlog dependency (asdaraujo #1380)
• Fixes racing condition when message is sent to broker before topic logs are created (asdaraujo #1293)
• Add kafka 1.0.1 release to test fixtures (dpkp #1437)

Logging / Error Messages

• Re-enable logging during broker version check (dpkp #1430)
• Connection logging cleanups (dpkp #1432)
• Remove old CommitFailed error message from coordinator (dpkp #1436)

Bugfixes

• Fix consumer poll stuck error when no available partition (ckyoog #1375)
• Increase some integration test timeouts (dpkp #1374)
• Use raw in case string overriden (jeffwidman #1373)
• Fix pending completion IndexError bug caused by multiple threads (dpkp #1372)

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)

Bugfixes

• Fix partition assignment race condition (jeffwidman #1240)
• Fix consumer bug when seeking / resetting to the middle of a compressed messageset (dpkp #1239)
• Fix traceback sent to stderr not logging (dbgasaway #1221)
• Stop using mutable types for default arg values (jeffwidman #1213)
• Remove a few unused imports (jameslamb #1188)

Client

• Refactor BrokerConnection to use asynchronous receive_bytes pipe (dpkp #1032)

Consumer

• Drop unused sleep kwarg to poll (dpkp #1177)
• Enable KafkaConsumer beginning_offsets() and end_offsets() with older broker versions (buptljy #1200)
• Validate consumer subscription topic strings (nikeee #1238)

Documentation

• Small fixes to SASL documentation and logging; validate security_protocol (dpkp #1231)
• Various typo and grammar fixes (jeffwidman)

Bugfixes

• Avoid multiple connection attempts when refreshing metadata (dpkp #1067)
• Catch socket.errors when sending / recving bytes on wake socketpair (dpkp #1069)
• Deal with brokers that reappear with different IP address (originsmike #1085)
• Fix join-time-max and sync-time-max metrics to use Max() measure function (billyevans #1146)
• Raise AssertionError when decompression unsupported (bts-webber #1159)
• Catch ssl.EOFErrors on Python3.3 so we close the failing conn (Ormod #1162)
• Select on sockets to avoid busy polling during bootstrap (dpkp #1175)
• Initialize metadata_snapshot in group coordinator to avoid unnecessary rebalance (dpkp #1174)

Client

• Timeout idle connections via connections_max_idle_ms (dpkp #1068)
• Warn, dont raise, on DNS lookup failures (dpkp #1091)
• Support exponential backoff for broker reconnections -- KIP-144 (dpkp #1124)
• Add gssapi support (Kerberos) for SASL (Harald-Berghoff #1152)
• Add private map of api key -> min/max versions to BrokerConnection (dpkp #1169)

Consumer

• Backoff on unavailable group coordinator retry (dpkp #1125)
• Only change_subscription on pattern subscription when topics change (Artimi #1132)
• Add offsets_for_times, beginning_offsets and end_offsets APIs (tvoinarovskyi #1161)

Producer

• Raise KafkaTimeoutError when flush times out (infecto)
• Set producer atexit timeout to 0 to match del (Ormod #1126)

Core / Protocol

• 0.11.0.0 protocol updates (only - no client support yet) (dpkp #1127)
• Make UnknownTopicOrPartitionError retriable error (tvoinarovskyi)

Test Infrastructure

• pylint 1.7.0+ supports python 3.6 and merge py36 into common testenv (jianbin-wei #1095)
• Add kafka 0.10.2.1 into integration testing version (jianbin-wei #1096)
• Disable automated tests for python 2.6 and kafka 0.8.0 and 0.8.1.1 (jianbin-wei #1096)
• Support manual py26 testing; dont advertise 3.3 support (dpkp)
• Add 0.11.0.0 server resources, fix tests for 0.11 brokers (dpkp)
• Use fixture hostname, dont assume localhost (dpkp)
• Add 0.11.0.0 to travis test matrix, remove 0.10.1.1; use scala 2.11 artifacts (dpkp #1176)

Logging / Error Messages

• Improve error message when expiring batches in KafkaProducer (dpkp #1077)
• Update producer.send docstring -- raises KafkaTimeoutError (infecto)
• Use logging's built-in string interpolation (jeffwidman)
• Fix produce timeout message (melor #1151)
• Fix producer batch expiry messages to use seconds (dnwe)

Documentation

• Fix typo in KafkaClient docstring (jeffwidman #1054)
• Update README: Prefer python-lz4 over lz4tools (kiri11 #1057)
• Fix poll() hyperlink in KafkaClient (jeffwidman)
• Update RTD links with https / .io (jeffwidman #1074)
• Describe consumer thread-safety (ecksun)
• Fix typo in consumer integration test (jeffwidman)
• Note max_in_flight_requests_per_connection > 1 may change order of messages (tvoinarovskyi #1149)

Core / Protocol

• Derive all api classes from Request / Response base classes (dpkp 1030)
• Prefer python-lz4 if available (dpkp 1024)
• Fix kwarg handing in kafka.protocol.struct.Struct (dpkp 1025)
• Fixed couple of "leaks" when gc is disabled (Mephius 979)
• Added max_bytes option and FetchRequest_v3 usage. (Drizzt1991 962)
• CreateTopicsRequest / Response v1 (dpkp 1012)
• Add MetadataRequest_v2 and MetadataResponse_v2 structures for KIP-78 (Drizzt1991 974)
• KIP-88 / KAFKA-3853: OffsetFetch v2 structs (jeffwidman 971)
• DRY-up the MetadataRequest_v1 struct (jeffwidman 966)
• Add JoinGroup v1 structs (jeffwidman 965)
• DRY-up the OffsetCommitResponse Structs (jeffwidman 970)
• DRY-up the OffsetFetch structs (jeffwidman 964)
• time --> timestamp to match Java API (jeffwidman 969)
• Add support for offsetRequestV1 messages (jlafaye 951)
• Add FetchRequest/Response_v3 structs (jeffwidman 943)
• Add CreateTopics / DeleteTopics Structs (jeffwidman 944)

Test Infrastructure

• Add python3.6 to travis test suite, drop python3.3 (exponea 992)
• Update to 0.10.1.1 for integration testing (dpkp 953)
• Update vendored berkerpeksag/selectors34 to ff61b82 (Mephius 979)
• Remove dead code (jeffwidman 967)
• Update pytest fixtures to new yield syntax (jeffwidman 919)

Consumer

• Avoid re-encoding message for crc check (dpkp 1027)
• Optionally skip auto-commit during consumer.close (dpkp 1031)
• Return copy of consumer subscription set (dpkp 1029)
• Short-circuit group coordinator requests when NodeNotReady (dpkp 995)
• Avoid unknown coordinator after client poll (dpkp 1023)
• No longer configure a default consumer group (dpkp 1016)
• Dont refresh metadata on failed group coordinator request unless needed (dpkp 1006)
• Fail-fast on timeout constraint violations during KafkaConsumer creation (harelba 986)
• Default max_poll_records to Java default of 500 (jeffwidman 947)
• For 0.8.2, only attempt connection to coordinator if least_loaded_node succeeds (dpkp)

Producer

• change default timeout of KafkaProducer.close() to threading.TIMEOUT_MAX on py3 (mmyjona 991)

Client

• Add optional kwarg to ready/is_ready to disable metadata-priority logic (dpkp 1017)
• When closing a broker connection without error, fail in-flight-requests with Cancelled (dpkp 1010)
• Catch socket errors during ssl handshake (dpkp 1007)
• Drop old brokers when rebuilding broker metadata (dpkp 1005)
• Drop bad disconnect test -- just use the mocked-socket test (dpkp 982)
• Add support for Python built without ssl (minagawa-sho 954)
• Do not re-close a disconnected connection (dpkp)
• Drop unused last_failure time from BrokerConnection (dpkp)
• Use connection state functions where possible (dpkp)
• Pass error to BrokerConnection.close() (dpkp)

Bugfixes

• Free lz4 decompression context to avoid leak (dpkp 1024)
• Fix sasl reconnect bug: auth future must be reset on close (dpkp 1003)
• Fix raise exception from SubscriptionState.assign_from_subscribed (qntln 960)
• Fix blackout calculation: mark last_attempt time during connection close (dpkp 1008)
• Fix buffer pool reallocation after raising timeout (dpkp 999)

Logging / Error Messages

• Add client info logging re bootstrap; log connection attempts to balance with close (dpkp)
• Minor additional logging for consumer coordinator (dpkp)
• Add more debug-level connection logging (dpkp)
• Do not need str(self) when formatting to %s (dpkp)
• Add new broker response errors (dpkp)
• Small style fixes in kafka.errors (dpkp)
• Include the node id in BrokerConnection logging (dpkp 1009)
• Replace %s with %r in producer debug log message (chekunkov 973)

Documentation

• Sphinx documentation updates (jeffwidman 1019)
• Add sphinx formatting to hyperlink methods (jeffwidman 898)
• Fix BrokerConnection api_version docs default (jeffwidman 909)
• PEP-8: Spacing & removed unused imports (jeffwidman 899)
• Move BrokerConnection docstring to class (jeffwidman 968)
• Move docstring so it shows up in Sphinx/RTD (jeffwidman 952)
• Remove non-pip install instructions (jeffwidman 940)
• Spelling and grammar changes (melissacrawford396 923)
• Fix typo: coorelation --> correlation (jeffwidman 929)
• Make SSL warning list the correct Python versions (jeffwidman 924)
• Fixup comment reference to _maybe_connect (dpkp)
• Add ClusterMetadata sphinx documentation (dpkp)

Legacy Client

• Add send_list_offset_request for searching offset by timestamp (charsyam 1001)
• Use select to poll sockets for read to reduce CPU usage (jianbin-wei 958)
• Use select.select without instance bounding (adamwen829 949)