21.9.0

Breaking API Changes

• finagle-thrift: Removed c.t.finagle.thrift.ThriftClient#newMethodIface and ThriftClient#thriftService, use c.t.f.thrift.ThriftClient#methodPerEndpoint. fc21cccf

Bug Fixes

• finagle-core/partitioning: Close balancers and their gauges when repartitioning. d0bd053d

Runtime Behavior Changes

• finagle: Upgrade to Netty 4.1.67.Final and netty-tcnative 2.0.40.Final. c373fc08
• finagle: Downgrade to Netty 4.1.66.Final cbfbef89
• finagle: Bump version of Jackson to 2.11.4. 19750a80
• finagle-core: OffloadFilter hands off work from Netty I/O thread to the offload CPU thread pool right after we enter the Finagle stack by default. Previously this could be enabled via a toggle. The com.twitter.finagle.OffloadEarly toggle has been removed. 2b5086fe

New Features

• finagle-mysql: introduce newRichClient(dest: String, label: String) method, which removes the need for extra boilerplate to convert the destination String to a c.t.finagle.Name when specifying both dest and label in String form. c211bfbe
• finagle-http, finagle-thriftmux: introduce client.withSni() API. Use this api to specify an SNI hostname for TLS clients. a8ec457b

Runtime Behavior Changes

• finagle: Update Caffeine cache library to version 2.9.1 d9e551a3

• finagle: Update ScalaCheck to version 1.15.4 145ab4aa

• finagle-core: change ServiceClosedException to extend FailureFlags and to be universally retryable e621e5ff

• finagle-http: remove the com.twitter.finagle.http.UseH2, com.twitter.finagle.http.UseH2CClients2, com.twitter.finagle.http.UseH2CServers and com.twitter.finagle.http.UseHttp2MultiplexCodecClient toggles. The configuration for c.t.finagle.Http.client and c.t.finagle.Http.server now default to using the HTTP/2 based implementation. To disable this behavior, use c.t.finagle.Http.client.withNoHttp2 and c.t.finagle.Http.server.withNoHttp2 respectively.

  Alternatively, new GlobalFlag's have been introduced to modify the default behavior of clients and servers that have not been explicitly configured, where the com.twitter.finagle.http.defaultClientProtocol and com.twitter.finagle.http.defaultServerProtocol flags can be set to HTTP/1.1 to modify the default client or server configuration, respectively. PHAB_ID=D625880`

• finagle-netty4: Finagle now reuses Netty "boss" (or parent) threads instead of creating a new thread per server. Netty parent threads are servicing the server acceptor, a relatively lightweight component that listens for new incoming connections before handing them out to the global worker pool. 5e9998fc

• finagle-http2: introduce optional parameter NackRstFrameHandling to enable or disable NACK conversion to RST_STREAM frames. 728aed03

• finagle-thrift, finagle-thriftmux: clients may start reporting (correctly) lower success rate. Previously server exceptions not declared in IDL were erroneously considered as successes. The fgix also improves failure detection and thus nodes previously considered as healthy by failure accrual policy may be considered as unhealthy. 3bba41c6

Bug Fixes

• finagle-core: Add BackupRequestFilter to client registry when configured. 56092e96
• finagle-thrift, finagle-thriftmux: clients now treat server exceptions not declared in IDL as failures, rather than successes, and do not skip the configured response classifier for failure accrual. 3bba41c6

New Features

• finagle-core: Introduce Dtab.limited, which is a process-local Dtab that will NOT be remotely broadcast for any protocol, where Dtab.local will be broadcast for propagation on supported protocols. For path name resolution, the Dtab.local will take precedence over the Dtab.limited, if the same path is defined in both, and both take precedence over the Dtab.base. The existing Dtab.local request propagation behavior remains unchanged. 2e06c669
• finagle-core: Add descriptions to RequestDraining, PrepFactory, PrepConn, and protoTracing modules in StackClient. Add descriptions to preparer and protoTracing modules in StackServer. 1ea1a3eb

Breaking API Changes

• finagle-memcached: Ketama Partitioned Client has been removed and the Partition Aware Memcached Client has been made the default. As part of this change, com.twitter.finagle.memcached.UsePartitioningMemcachedClient toggle has been removed, and it no longer applies. 2628b84b

Runtime Behavior Changes

• finagle-core: Broadcast context keys lookups are now case insensitive. This change is backwards compatible as the marshalled key id is unchanged. Although enabled by default, this change will be temporarily sitting behind a toggle, com.twitter.finagle.context.MarshalledContextLookupId that can be used to turn off this change. 69c29093

Deprecations

• finagle-core: The ServerBuilder pattern has been deprecated. Use the stack server pattern instead. 386171ad

New Features

• finagle-http2: Added c.t.f.http2.param.EnforceMaxConcurrentStreams which allows users to configure http2 clients to buffer streams once a connection has hit the max concurrent stream limit rather than rejecting them. A buffered_streams gauge has been added to track the current number of buffered streams. c6d5f520
• finagle-mux: Added support for TLS snooping to the mux protocol. This allows a thriftmux server to start a connection as TLS or follow the existing upgrade pathway at the leisure of the client. This also allows the server to support opportunistic TLS and still downgrade to vanilla thrift. 60705fd2
• finagle-netty4: Added a new counter to keep track of the number of TLS connections that were started via snooping. 5569615e
• finagle-thrift: Thrift(Mux) clients and servers now fill in a c.t.f.Thrift.param.ServiceClass stack param with the runtime class corresponding to a IDL-generated service stub. 04a2de2c

Breaking API Changes

• finagle-core: c.t.f.param.Logger has been removed. Use external configuration supported by your logging backend to alter settings of com.twitter.finagle logger. 99982cda

Runtime Behavior Changes

• finagle-http: Make handling of invalid URI consistent across client implementations. There are behavioral inconsistencies amongst the current HTTP client implementations:

  Our HTTP/1.x clients allow for submitting requests that contain non-ASCII characters and invalid character encoded sequences, while our HTTP/2 clients will either mangle the URI and strip out non-ASCII characters within the Netty pipeline or result in an UnknownChannelException when attempting to parse invalid character encoded sequences. With this change, we now consistently propagate an InvalidUriException result, which is marked as NonRetryable for all HTTP client implementations. All HTTP server implementations maintain behavior of returning a 400 Bad Request response status, but now also correctly handle invalid character encoded sequences. fa58caab

Bug Fixes

• finagle-core: Failed writes on Linux due to a remote peer disconnecting should now be properly seen as a c.t.f.ChannelClosedException instead of a c.t.f.UnknownChannelException. 6214e6ac
• finagle-http2: The streams gauge is now correctly added for http2 connections over TLS. c6d5f520
• finagle-core: c.t.f.n.NameTreeFactory will now discard empty elements in c.t.f.NameTree.Unions with zero weight. cf73946d
• finagle-http: All HTTP server implementations consistently return a 400 Bad Request response status when encountering a URI with invalid character encoded sequences. fa58caab

New Features

• finagle-core: Introduce a new ResponseClassifier ('IgnoreIRTEs') that treats com.twitter.finagle.IndividualRequestTimeoutExceptions as ResponseClass.Ignored. This response classifier is useful when a client has set a super low RequestTimeout and receiving a response is seen as 'best-effort'. e897bd67
• finagle-mysql: Introduce support of opportunistic TLS to allow mysql clients with enabled TLS to speak over encrypted connections with MySQL servers where TLS is on, and fallback to plaintext connections if TLS is switched off on the server side. e02495aa

Runtime Behavior Changes

• finagle-core: The "failures" counter is changed to be created eagerly, when no failure happens, the counter value is 0. d81a57c6

New Features

• finagle-core: Added value ForceWithDtab to flag -com.twitter.finagle.loadbalancer.exp.apertureEagerConnections that forces the aperture load balancer to eagerly connect, even in staging environments where Dtab locals are set. 9dab522d
• finagle-core: Introduce a new Backoff to create backoffs based on varies strategies, where backoffs are calculated on the fly, instead of being created once and memoized in a Stream. Also introduced Backoff.fromStream(Stream) and Backoff.toStream to help with migration to the new API. 91d24c33
• finagle-netty4: Upgrade to Netty 4.1.59.Final and TcNative 2.0.35.Final. ee6ced91
• finagle-http: Integrate Kerberos authentication filter to finagle http client and server. e3bfa0c3 eefc21c8
• finagle-core: Provided c.t.f.ssl.TrustCredentials.X509Certificates to enable directly passing X509Certificate instead of passing a File. 61c2a596

Breaking API Changes

• finagle: Builds are now only supported for Scala 2.12+ 8a48eab7
• finagle-core: Changed flag -com.twitter.finagle.loadbalancer.exp.apertureEagerConnections" from having Boolean values true or false to EagerConnectionsType` values Enable, Disable, and ForceWithDtab. 9dab522d
• finagle-mysql: The constructor of c.t.f.mysql.transport.MysqlBufReader now takes an underlying c.t.io.ByteReader. Prior uses of the constructor, which took a c.t.io.Buf, should migrate to using c.t.f.mysql.transport.MysqlBufReader.apply instead. ad73f92d
• finagle-base-http: Kerberos jaas config KerberosConfiguration is replaced with ServerKerberosConfiguration and ClientKerberosConfiguration concrete classes.

Runtime Behavior Changes

• finagle: Revert to scala version 2.12.12 due to https://github.com/scoverage/sbt-scoverage/issues/319 c2db97c2
• finagle: Bump scala version to 2.12.13 b8e4e0ac
• finagle-core: Move helper tracing methods like traceLocal in Trace into the Tracing class. This allows cheaper use of these APIs by first capturing a Trace via Trace#apply, avoiding the extra lookups that will add overhead on the request path. ec0097cd.
• finagle-core: c.t.finagle.InetResolver, c.t.finagle.builder.ClientBuilder, c.t.finagle.liveness.FailureAccrualFactory, c.t.finagle.liveness.FailureAccrualPolicy, c.t.finagle.param.ClientParams, c.t.finagle.param.SessionQualificationParams, c.t.finagle.service.FailFastFactory, c.t.finagle.service.RequeueFilter, c.t.finagle.service.Retries, c.t.finagle.service.RetryFilter, and c.t.finagle.service.RetryPolicy will accept the new c.t.finagle.service.Backoff to create backoffs. Services can convert a Stream to/from a Backoff with Backoff.fromStream(Stream) and Backoff.toStream. 91d24c33
• finagle-core: remove the com.twitter.finagle.loadbalancer.apertureEagerConnections Toggle and change the default behavior to enable eager connections for c.t.f.loadbalancer.ApertureLeastLoaded and c.t.f.loadbalancer.AperturePeakEwma load balancers. The state of the com.twitter.finagle.loadbalancer.apertureEagerConnections GlobalFlag now also defaults to enable this feature (Enable. You can disable this feature for all clients via setting the com.twitter.finagle.loadbalancer.apertureEagerConnections GlobalFlag to Disable for your process. (i.e. -com.twitter.finagle.loadbalancer.apertureEagerConnections=Disable). ef8d536e

Deprecations

• finagle-core: Backoff.fromJava is marked as deprecated, since the new Backoff is java-friendly. For services using Stream.iterator on the old Backoff, please use the new API Backoff.toJavaIterator to acquire a java-friendly iterator. 91d24c33

New Features

• finagle-zipkin-core: Record zipkin.sampling_rate annotation to track sampling rate at trace roots. 2269eb6b

• finagle-core: Added variant of c.t.f.Address.ServiceFactory.apply that does not require specifying c.t.f.Addr.Metadata and defaults to c.t.f.Addr.Metadata.empty. 11971f0f

• finagle-core: Added variant of c.t.f.Name.bound which takes a c.t.f.Service as a parameter. Tying a Name directly to a Service can be extremely useful for testing the functionality of a Finagle client. 1422ffd5

• finagle-mux: Added variant of c.t.f.mux.Request.apply and c.t.f.mux.Requests.make which takes only the body of the Request (in the form of c.t.io.Buf) as a parameter. This is useful for when the path value of a Request is not used by the server (e.g. testing). 3ca46304

Runtime Behavior Changes

• finagle-memcached: The log level of messages pertaining to whether a Memcached client is using the older non-partitioned or the newer partitioned version has been lowered. These messages are no longer written at an 'info' level. 4bce560a

New Features

• finagle-core: Add clnt/<FilterName>_rejected annotation to filters that may throttle requests, including c.t.finagle.filter.NackAdmissionFilter and c.t.finagle.filter.RequestSemaphoreFilter. 66857683
• finagle-http: Record http-specific annotations including http.status_code and http.method. See details at https://github.com/open-telemetry/opentelemetry-specification/tree/master/specification/trace 78d93fde

Bug Fixes

• finagle-core: Fix wraparound bug in Ring.weight, as reported by @nvartolomei c4dc4fdc
• finagle-mysql: Update the UTF8 character set to cover those added in MySQL 8. 25e581bb
• finagle-thriftmux: Fixed a bug where connections were not established eagerly in ThriftMux MethodBuilder even when eager connections was enabled. ec67d48a

Runtime Behavior Changes

• finagle-mysql: Don't use the full query when adding tracing annotations. b215d255

New Features

• finagle-core: Add a new stat (histogram) that reports how long a task has been sitting in the offload queue. This instrumentation is sampled at the given interval (100ms by default) that can be overridden with a global flag com.twitter.finagle.offload.statsSampleInterval. a7ebf2e1
• finagle-core: Add a new experimental flag com.twitter.finagle.offload.queueSize that allows to put bounds on the offload queue. Any excess work that can't be offloaded due to a queue overflow is run on IO (Netty) thread instead. Put this way, this flag enables the simplest form of backpressure on the link between Netty and OffloadFilter. af228ca6
• finagle-netty4: Add ExternalClientEngineFactory to the open source version of Finagle. This SslClientEngineFactory acts as a better example of how to build custom client and server engine factories in order to reuse SSL contexts for performance concerns. 931785d9
• finagle-core: Provide com.twitter.finagle.naming.DisplayBoundName for configuring how to display the bound Name for a given client in metrics metadata. 67be8e1e
• finagle-core: Provide ClientParamsInjector, a class that will be service-loaded at run-time by Finagle clients, and will allow generic configuration of all sets of parameters. b7bb5afc

Breaking API Changes

• finagle-core: Move DarkTrafficFilter and AbstractDarkTrafficFilter from the experimental finagle-exp to supported finagle-core. The package containing these classes changed from c.t.finagle.exp to c.t.finagle.filter. 0ecaa5e7
• finagle-core, finagle-thrift: Move ForwardingWarmUpFilter and ThriftForwardingWarmUpFilter from the experimental finagle-exp to supported finagle-core, and finagle-thrift, respectively. The package containing ForwardingWarmUpFilter changed from c.t.finagle.exp to c.t.finagle.filter, and the package containing ThriftForwardingWarmUpFilter changed from c.t.finagle.exp to c.t.finagle.thrift.filter. e725bc86
• finagle-core: FailureAccrualFactory.isSuccess has been replaced with the method def classify(ReqRep): ResponseClass to allow expressing that a failure should be ignored. d586bd24

Runtime Behavior Changes

• finagle-core: Use Scala default implementation to calculate Hashcode and equals method for ServiceFactoryProxy. c473b395
• finagle: Update build.sbt to get aarch64 binaries and try the fast path acquire up to 5 times before failing over to the AbstractQueuedSynchronizer slow path in NonReentrantReadWriteLock for Arm64. d45dfb02

Bug Fixes

• finagle-core: Users should no longer see the problematic java.lang.UnsupportedOperationException: tail of empty stream when a c.t.f.s.RetryPolicy is converted to a String for showing. e7ec247d

Breaking API Changes

• finagle-thrift: Change the partition locator function getLogicalPartitionId in PartitioningStrategy from Int => Int to Int => Seq[Int], which supports many to many mapping from hosts and logical partitions. ab641adc

Runtime Behavior Changes

• finagle-core: Disable eager connections for balancers with a non 1.0 weight. 11eae0d6