20.12.0

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

New Features

• finagle-core: Add RelativeName field to Metric Metadata and populate it for
  client and server metrics. de589ffa
• finagle-scribe: Add c.t.finagle.scribe.Publisher for publishing messages to a
  Scribe process. 7723a949

Runtime Behavior Changes

• finagle: Bump version of Jackson to 2.11.2. 6c6c882a

Bug Fixes

• finagle-core: The TraceId alternative constructor now forwards the traceIdHigh parameter to
  the primary constructor. 567e8d66

20.8.1

New Features

• finagle-thriftmux: Add MethodBuilder specific APIs for ThriftMux partition aware client.
  e2f467c1

20.8.0

Runtime Behavior Changes

• finagle-netty4-http: Post, Put, Patch non-streaming outbound requests with empty bodies will
  be added the Content-Length header with value 0. 9ce18e85
• finagle-core: A ServiceFactory created by ServiceFactory.const/constant propagates the wrapped
  service status. 3347c095
• finagle-http: c.t.f.http.filter.PayloadSizeFilter no longer adds an annotation on each
  streaming chunk and instead aggregates the byte count and adds a single record on stream
  termination. e87b1c35
• finagle-zipkin-scribe: zipkin scribe log_span prefix replaced with scribe. zipkin-scribe/scribe/<stats>. 5b100ee9

New Features

• finagle-core: introduce type-safe ReqRep variant 459daf68
• finagle-core: Added a new variant of Filter.andThenIf which allows passing the parameters
  as individual parameters instead of a Scala tuple. fb071d9b
• finagle-core: new metric (counter) for traces that are sampled. finagle/tracing/sampled 1d6503e0
• finagle-netty4: Add the c.t.f.netty4.Netty4Listener.MaxConnections param that can be used
  to limit the number of connections that a listener will maintain. Connections that exceed
  the limit are eagerly closed. 9991aae3
• finagle-thrift: Added java-friendly c.t.f.thrift.exp.partitioning.ClientHashingStrategy and
  c.t.f.thrift.exp.partitioning.ClientCustomStrategy create methods, and added java-friendly
  c.t.f.thrift.exp.partitioning.RequestMergerRegistry#addRequestMerger and
  c.t.f.thrift.exp.partitioning.ResponseMergerRegistry#addResponseMerger to make partitioning
  easier to use from Java. e0d78d14

Breaking API Changes

• finagle-core: ReqRep can no longer be created via new ReqRep(..). Please use
  ReqRep.apply(..) instead.
  459daf68
• finagle-thrift: Updated the c.t.f.thrift.exp.partitioning.ClientHashingStrategy and the
  c.t.f.thrift.exp.partitioning.ClientCustomStrategy to take constructor arguments instead
  of needing to override methods on construction. e0d78d14
• finagle-zipkin-core: Removed unused statsReceiver constructor argument from RawZipkinTracer. 5b100ee9

20.7.0

Breaking API Changes

• finagle-core: Correct the spelling of Tracing.recordClientSendFrargmet() to
  Tracing.recordClientSendFragment() 30726c01
• finagle-redis: Use StrictKeyCommand for XDEL d174f9d6
• finagle-toggle: Toggle.isDefinedAt(i: Int) has become Toggle.isDefined. Additionally, a new method Toggle.isUndefined has been added. 3bb78ce8
• finagle-zipkin-scribe: The scribe.thrift file was moved to finagle-thrift/src/main/thrift under a new
  namespace. com.twitter.finagle.thrift.scribe.(thrift|thriftscala) 01a20b79

Bug Fixes

• finagle-zipkin-scribe: The scribe client should be configured using the NullTracer. Otherwise, spans
  produced by the client stack will be sampled at initialSampleRate. 0446dd3e

Runtime Behavior Changes

• finagle-core: FailFastFactory is now disabled at runtime when a client's destination has only
  one endpoint, since the client cannot do anything meaningful by breaking the circuit early.
  This is recommended as a best practice anyway, now it's the default behavior. Less things
  to configure and worry about! f2c100e8
• finagle-core: namer annotations are prefixed with "clnt/". c8680fff
• finagle-core: namer.success & namer.failure are not annotated as they are not request based.
  namer.tree annotation was also removed to reduce the size of traces. c8680fff
• finagle-core: The offload filter client annotation is annotated under the child request span instead of
  its parent. The offload filter annotations are also changed to be binary annotations with the key
  (clnt|srv)/finagle.offload_pool_size and the value being the pool size 011f096d
• finagle-memcached: The key in RetrievalCommand are ommited in traces. The total number of Hits
  and Misses are annotated via a counter instead under clnt/memcached.(hits/misses) 6fd0e2c9

Breaking API Changes

• finagle-core: Migrated List[Tracer] to Seq[Tracer] in Tracing, and tracersCtx.
  cb06890b
• finagle-core: PayloadSizeFilter and WireTracingFilter are now public APIs.
  fc1951a5
• finagle-zipkin-core: initialSampleRate flag will now fail if the sample rate is not in the range
  [0.0, 1.0]. 180f333c
• finagle-mysql: mysql client annos are prefixed with clnt/ 37d55c2a

New Features

• finagle-thrift: Expose c.t.f.thrift.exp.partitioning.PartitioningStrategy,
  the bundled PartitioningStrategy APIs are public for experiments.
  bf1d47be
• finagle-http: Add LoadBalancedHostFilter to allow setting host header after LoadBalancer
  5304ce69
• finagle-core: Trace the request's protocol identified by the ProtocolLibrary of the client
  stack. This is annotated under clnt/finagle.protocol. 464bbeb6
• finagle-core: Add letTracers to allow setting multiple tracers onto the tracer stack.
  cb06890b
• finagle-core: DeadlineFilter now exposes a metric admission_control/deadline/remaining_ms
  which tracks the remaining time in non-expired deadlines on the server side. An increase in this
  stat, assuming request latency is constant and timeout configurations upstream have not changed,
  may indicate that upstream services have become slower. 939f9a3e
• finagle-redis: Make partitionedClient accessible. 7ba107e1
• finagle-core, finagle-http, finagle-thriftmux: introduce MethodBuilder maxRetries
  configuration. A ThriftMux or HTTP method can now be configured to allow a specific number of
  maximum retries per request, where the retries are gated by the configured RetryBudget. This
  configuration can be applied via Http.client.methodBuilder(name).withMaxRetries(n) or
  ThriftMux.client.methodBuilder(name).withMaxRetries(n). 4328896d
• finagle-memcached: Annotate the shard id of the backend the request will reach. 6fd0e2c9

Bug Fixes

• finagle-zipkin-core: Remove flush and late-arrival annotations, which artificially extend
  trace durations. 967ef1fc
• finagle-core: namer annotations are added at the Service level instead of ServiceFactory as
  traces are intended to be request based c8680fff

Runtime Behavior Changes

• finagle: Bump jackson version to 2.11.0. 696bb515

New Features

• finagle-redis: Add ConnectionInitCommand stack to set database and password.
  9fe05301

• finagle-mysql: Add ConnectionInitSql stack to set connection init sql. bd4411dd

Runtime Behavior Changes

• finagle-core: Requeued reqeuests due to the c.t.finagle.service.RequeueFilter will generate
  their own spanId. af490773

Bug Fixes

• finagle-core: Restrict OffloadFilter from allowing interruption of the work performed in the worker pool. This is to ensure that the worker thread isn't interruptible, which is a
  behavior of certain FuturePool implementations. f0af6ad7 59f9f2b5

• finagle-netty4: ChannelStatsHandler will now only count the first channel close(..) call when incrementing the closes counter. 3fa91944

Breaking API Changes

• finagle-toggle: Removed abstract type for c.t.finagle.Toggle, all Toggles are of type Int.
  This is to avoid Integer auto-boxing when calling Toggle.apply, thus to improve overall toggle performance. c81a87b0

• finagle-core: Retried requests due to the c.t.finagle.service.RetryFilter will generate their
  own spanId. 762471a0

New Features

• finagle-thrift/thriftmux: Thrift and ThriftMux client side can set a sharable
  TReusableBuffer by withTReusableBufferFactory. 9213ca35

Breaking API Changes

• finagle-partitioning: Rename c.t.finagle.partitioning.CacheNode and CacheNodeMetadata
  to c.t.finagle.partitioning.PartitionNode and PartitionNodeMetadata. d32f0c25

• finagle-partitioning: Rename c.t.finagle.partitioning.KetamaClientKey to HashNodeKey
  2d0cd33e

Bug Fixes

• finagle-base-http: RequestBuilder headers use SortedMap to equalize keys in different caps.
  setHeader keys are case insensitive, the last one wins. 535f324c

New Features

• finagle-opencensus-tracing: Add support for providing a custom TextFormat for header
  propagation. a02d377a

Runtime Behavior Changes

• finagle-netty4: When not using the JDK implementation, the Netty reference counted SSL
  types are used which move SSL cleanup out of the GC cycle, reducing pause durations.
  466aa5bf

• finagle-base-http: Support for the SameSite cookie attribute is now on by default. This can
  be manipulated via the com.twitter.finagle.http.cookie.supportSameSiteCodec flag. This means
  that cookies that have a value other than Unset for the sameSite field will have the
  attribute encoded (by servers) and decoded (by clients). See this
  Chromium blog post
  for more information about the SameSite attribute. f96c3729

• finagle-core: The default NullTracer for ClientBuilder has been removed. Affected clients may
  now see tracing enabled by default via the Java ServiceLoader, as described in the
  Finagle User's Guide. 6b3f0940

• finagle-http2: The HTTP/2 frame logging tools now log at level INFO. This is symmetric with
  the behavior of the ChannelSnooper tooling which serves a similar purpose which is to aid
  in debugging data flow and isn't intended to be enabled in production. 78e4596b

Bug Fixes

• finagle-zipkin-scribe: add a logical retry mechanism to scribe's TRY_LATER response 23ff595b

• finagle-http2: Initialize state in H2Pool before use in the gauge to avoid a
  NullPointerException. 289de8a3

• finagle-http2: HTTP/2 server pipeline now traps close calls to ensure that
  events from the initial HTTP/1.x pipeline don't close the HTTP/2 session. For
  example, the initial pipeline was subject to session timeouts even though the
  tail of the socket pipeline was effectively dead. Closing of HTTP/2 server
  pipelines is now handled through the H2ServerFilter. 670dbf74

• finagle-http2: HTTP/2 servers clean out unused channel handlers when upgrading
  from a HTTP/1.x pipeline, removing some traps such as unintended timeouts.
  3dfe8226

• finagle-opencensus-tracing: Fixed internal server error when invalid or no propagation headers
  are provided. a02d377a

• finagle-zipkin-scribe: export application metrics under a consistent zipkin-scribe scope. Finagle client
  stats under clnt/zipkin-scribe a17659dd

Breaking API Changes

• finagle-zipkin-scribe: update the deprecated FutureIface to MethodPerEndpoint 23ff595b

• finagle-zipkin-scribe: Coalesce ScribeRawZipkinTracer apply methods into two simple ones. a17659dd

• finagle-zipkin-scribe: DefaultSampler moved to c.t.f.zipkin.core in finagle-zipkin-core. ac9c7ec1

• finagle-zipkin-scribe: initialSampleRate GlobalFlag is moved to finagle-zipkin-core, under the same package
  scope c.t.f.zipkin. ac9c7ec1

New Features

• finagle-memcached: Upgrade to Bijection 0.9.7. de0ec2c6
• finagle-opencensus-tracing: Enables cross-build for 2.13.0. fee83b10
• finagle-thriftmux: Add support for automatically negotiating compression between a client
  and server. Off by default, clients and servers must be configured to negotiate.
  d42c87a9
• finagle-stats: Enables cross-build for 2.13.0. 4144d73c
• finagle-stats-core: Enables cross-build for 2.13.0. 4144d73c
• finagle-serversets: Add generic metadata support in ServerSet. Add support for announcing the
  generic metadata via ZkAnnouncer. Add support to resolve the generic metadata via Zk2Resolver
  180bb925

Breaking API Changes

• finagle-partitioning: ZKMetadata case class has a new default argument breaking API for
  Java users. 180bb925
• finagle-serversets: Endpoint case class has a new metadata argument. 180bb925

New Features

• finagle-core, finagle-exp: Add annotations to DarkTrafficFilter to identify which span
  is dark, as well as which light span it correlates with. ba351f4d
• finagle-core: Introduce Trace#traceLocal for creating local spans within a trace context.
  1c6d5d24

Runtime Behavior Changes

• finagle: Upgrade to jackson 2.9.10 and jackson-databind 2.9.10.1 e333c839
• finagle-core: Per-method metrics on MethodBuilder are now created lazily, so if you have
  methods that you don't use, the associated metrics won't be exported. 6be5dc48
• finagle-mysql: The RollbackFactory no longer attempts to roll back if the underlying
  session is closed since it is highly unlikely to succeed. It now simply poisons the
  session and calls close. 99135e00
• finagle-netty4: Change the 'connection_requests' metric to debug verbosity.
  a6dc1296
• finagle-serversets: Ensure ZkSession#retrying is resilient to ZK host resolution failure.
  7125026a
• finagle-thrift: Per-method metrics are now created lazily, so if you have methods on a Thrift
  service that you don't use, the associated metrics won't be exported. 6be5dc48
• finagle-zipkin-core: Tracing produces microsecond resolution timestamps in JDK9 or later.
  08a926c6
• finagle-core: Trace#time and Trace#timeFuture no longer generate timestamped annotations or
  silently discard timing information. They now instead generate a BinaryAnnotation containing
  the timing information. In order to also get timestamped Annotations for when the operation
  began and ended, use in conjunction with Trace#traceLocal. 1c6d5d24

Breaking API Changes

• finagle-core: The RetryPolicy companion object is no longer a JavaSingleton.
  9ffb3d13
• finagle-thrift: The RichClientParam constructors are now all either
  deprecated, so to construct it, you must call one of the RichClientParam.apply
  methods. 6be5dc48

Deprecations

• finagle-core: Deprecate Tracing#record(message, duration) as it does not have the intended
  effect and silently discards any duration information in the resulting trace. Instead you should
  use either Tracing#recordBinary or a combination of Trace#traceLocal and Trace#time.
  1c6d5d24

Bug Fixes

• finagle-core: ClosableService client stack module that prevents the reuse of closed services
  when FactoryToService is not set. This is important for clients making use of the newClient
  api. c64bea09

New Features

• finagle-base-http: The Uri class now provides access publicly to its
  path, which is the request uri without the query parameters.
  f40fe447
• finagle-mysql: Adding native support to finagle-mysql for MySQL JSON Data Type. A client
  can now use jsonAsObjectOrNull[T] or getJsonAsObject[T] APIs on c.t.f.mysql.Row to
  read the underlying json value as type T or use jsonBytesOrNull API to get a raw byte
  array of the the json column value. 4d403051
• MySQL integration tests can now run on a port other than the default (3306). Add a port
  property to .finagle-mysql/integration-test.properties to customize the value.
  4d403051

Runtime Behavior Changes

• finagle: Upgrade to Netty 4.1.43.Final and netty-tcnative 2.0.26.Final. cfaaa471
• finagle: Add initial support for JDK 11 compatibility. 04def84b
• finagle: Upgrade to caffeine 2.8.0 c335b29e
• finagle-http2: Nacks in the form of RST(STREAM_REFUSED | ENHANCE_YOUR_CALM) no
  longer surface as a RstException, instead opting for a generic Failure to be
  symmetric with the HTTP/1.x nack behavior. cb67fa33
• finagle-mux: The mux handshake latency stat has be changed to Debug
  verbosity. 0eb2cfb6
• finagle-serversets: finagle/serverset2/stabilizer/notify_ms histogram has been downgraded to
  debug verbosity. 30d3d0ea

Breaking API Changes

• finagle-base-http: c.t.f.http.codec.HttpContext moved into c.t.f.http.codec.context.HttpContext
  cc29b265

New Features

• finagle-partition: Enables cross-build for 2.13.0. 89f06885
• finagle-exception: Enables cross-build for 2.13.0. d90ae646
• finagle-exp: Enables cross-build for 2.13.0. 32bc9f48
• finagle-mysql: Enables cross-build for 2.13.0. ef31c99b
• finagle-{mux,thrift,thrift-mux}: Enables cross-build for 2.13.0. 47ee31fd
• finagle-redis: Enables cross-build for 2.13.0. d90ae646
• finagle-tunable: Enables cross-build for 2.13.0. 69ded534
• finagle-grpc-context: Enables cross-build for 2.13.0. 65963f58
• finagle-thrift: Pass a factory to create a TReusableBuffer as the parameter of a finagle client
  to allow multiple clients share one TReusableBuffer. 05b2ec71

Runtime Behavior Changes

• finagle-base-http: Better performance for the default HeaderMap.add method for headers with
  the same name. 1fab9386
• finagle-http2: H2ServerFilter will no longer swallow exceptions that fire via
  exceptionCaught in the Netty pipeline. 12621ff8
• finagle-http: Remove legacy HTTP/2 client implementation and make the MultiplexHandler-based
  implementation the default HTTP/2. b6d0aa19

Breaking API Changes

• finagle-core: c.t.f.l.FailureAccrualFactory's didMarkDead() changed to didMarkDead(Duration).
  The Duration is the length of time the endpoint is marked dead. fe2f43a3

Bug Fixes

• finagle-mux: Mux now properly propagates Ignorable failures multiple levels for superseded
  backup requests. This allows for more accurate success rate metrics for downstream services,
  when using backup requests.
  21b181e8

New Features

• finagle-{core,init,toggle,netty4}: Enables cross-build for 2.13.0. f21a54e0
• finagle-base-http: Add None as a valid SameSite header value. 0c43561a

Breaking API Changes

• finagle-core: The constructor on c.t.f.filter.NackAdmissionFilter used for testing that
  took an Ema.Monotime has been removed. 38fae802
• finagle-core: The Adddress.ServiceFactory variant has been promoted from experimental
  status and moved to be properly part of c.t.f.Address. 68cf34b8
• finagle-http: improve performance of c.t.f.http.filter.StatsFilter. This results in two notable
  API changes: 1. There is a private[filter] constructor which can take a () => Long for
  determining the current time in milliseconds (the existing StatsFilter(StatsReceiver)
  constructor defaults to using Stopwatch.systemMillis for determining the current time in
  milliseconds. 2. The protected count(Duration, Response) method has been changed to
  private[this] count(Long, Response) and is no longer part of the public API.
  f6ce4529
• finagle-partitioning: the hash-based routing that memcached uses has been relocated to a new
  top-level module so that it can be used more broadly across protocols. This results
  in several classes moving to the c.t.f.partitioning package: 1. The Memcached.param.EjectFailedHost, KeyHasher, and NumReps parameters are now
  available under c.t.f.partitioning.param 2. The FailureAccrualException and CacheNode definitions are now in the c.t.f.paritioning
  package. 3. The ZkMetadata class has moved to c.t.f.p.zk and the finagle-serverset module now depends
  on finagle-partitioning.
  f27073dc

Runtime Behavior Changes

• finagle-http: c.t.f.http.service.NotFoundService has been changed to no longer
  use Request.response. Use of Request.response is deprecated and discouraged.
  acac9c38
• finagle-mysql: Handshaking for the MySQL 'Connection Phase' now occurs as part of session
  acquisition. As part of this change, the
  com.twitter.finagle.mysql.IncludeHandshakeInServiceAcquisition toggle
  has been removed and it no longer applies. cd4877c1
• finagle: Upgrade to Netty 4.1.39.Final. 001b0940
• finagle-http: Enable Ping Failure Detection for MultiplexHandler based HTTP/2 clients. Note that
  the Ping Failure Detection implementation has been removed completely from the
  non-MultiplexHandler based HTTP/2 client. 8af32742
• finagle: Added a dependency on Scala Collections Compat 2.1.2. f21a54e0

Bug Fixes

• finagle-base-http: Removes the Cookie header of a c.t.f.http.Message whenever its cookie map
  becomes empty. f9b76a0f

Breaking API Changes

• finagle-core: The contents of the c.t.f.dispatch.GenSerialClientDispatcher object have been
  moved to the new c.t.f.dispatch.ClientDispatcher object. The stats receiver free constructors
  of GenSerialClientDispatcher and SerialClientDispatcher have been removed.
  4b0493c6
• finagle-thrift: The deprecated ReqRepThriftServiceBuilder object has been
  removed. Users should migrate to ReqRepMethodPerEndpointBuilder. f1c4d589

Runtime Behavior Changes

• finagle-core: Failed reads on Linux due to a remote peer disconnecting should now be properly
  seen as c.t.f.ChannelClosedException instead of a c.t.f.UnknownChannelException.
  b06fab3e
• finagle: Upgrade to Jackson 2.9.9. 464ae751
• finagle: Upgrade to Netty 4.1.38.Final. 23532f19

New Features

• finagle-http: Measure streaming (message.isChunked) chunk payload size with two new histograms:
  stream/request/chunk_payload_bytes and stream/response/chunk_payload_bytes, they are
  published with a debug verbosity level. These chunk payload sizes are also traced via the same
  trace keys. 11f4e32

• finagle-base-http: Add support for new "b3" tracing header. 8721837

• finagle-core: Allow to not bypass SOCKS proxy for localhost by using the GlobalFlag
  -com.twitter.finagle.socks.socksProxyForLocalhost 5521bc8

• finagle-core: OffloadFilter flag to reduce network contention. 2bd4d61

• finagle-exp: Add private c.t.f.exp.ConcurrencyLimitFilter for rejecting requests
  that exceed estimated concurrency limit e331491

Runtime Behavior Changes

• finagle-http: c.t.f.http.Cors has been changed to no longer use the c.t.f.http.Response
  associated with the passed in c.t.f.http.Request. 455718a

• finagle-http: c.t.f.http.filter.ExceptionFilter has been changed to no longer
  use the c.t.f.http.Response associated with the passed in. 54d4acf

• finagle-http: Optimize creation of new Http Dispatchers by re-using created metrics and loggers.
  9156f0f

Breaking API Changes

• finagle-base-http: Removed the methods setStatusCode and getStatusCode from
  c.t.f.http.Response which have been deprecated since 2017. 20b37b0

• finagle-core: All deprecated c.t.f.builder.ServerBuilder#build methods have
  been removed. Users should migrate to using the build method which takes a
  ServiceFactory[Req, Rep] as a parameter. 7ae208d

• finagle-core: The c.t.f.ssl.client.SslClientEngineFactory#getHostname method has been removed.
  All uses should be changed to use the getHostString method of SslClientEngineFactory instead.

• finagle-http: The setOriginAndCredentials, setMaxAge, setMethod, and setHeaders methods
  of c.t.f.http.Cors.HttpFilter are no longer overridable. 455718a

• finagle-http: The details of the c.t.f.Http.HttpImpl class are meant to be implementation
  details so the class constructor was made private along with the fields. Along these same lines
  the c.t.f.Http.H2ClientImpl.transporter method has been moved to a private location.
  1338e50

Bug Fixes

• finagle-core: Ensure ClientDispatcher queueSize gauge is removed on transport
  close, instead of waiting for clean-up at GC time. 963e9b8

• finagle-http2: Don't propagate stream dependency information for the H2 client.
  a2e6c0b

New Features

• finagle-core: SSL/TLS session information has been added to c.t.f.ClientConnection.
  69a28c10
• finagle-core: Add a Stack Module with 7 parameters for convenience sake. 6f9d7f0d
• finagle-core: For both, servers and clients, introduce a way to shift application-level future
  callbacks off of IO threads, into a given FuturePool or ExecutorService.
  Use withExecutionOffloaded configuration method (on a client or a server) to access
  new functionality. 40431bb4
• finagle-http: Added counters for request/response stream as: stream/request/closed,
  stream/request/failures, stream/request/failures/<exception_name>, stream/request/opened,
  stream/request/pending and stream/response/closed, stream/response/failures,
  stream/response/failures/<exception_name>, stream/response/opened, stream/response/pending.
  The counters will be populated when isChunked is set to true, the failures counters will be
  populated when isChunked is set to true and the stream fails before it has been fully read in the
  request and response respectively. d9b69bdc
• finagle-http: Add two new API variants in CookieMap: addAll and removeAll that allow for
  adding and removing cookies in bulk, without triggering a header rewrite on each item.
  4127cf6d
• finagle-mysql: finagle-mysql now supports using SSL/TLS with MySQL. SSL/TLS can be turned on by
  calling withTransport.tls(sslClientConfiguration) with a specified
  c.t.f.ssl.client.SslClientConfiguration. 0b6c20ac

Runtime Behavior Changes

• finagle: Upgrade to Netty 4.1.35.Final and netty-tcnative 2.0.25.Final.
  9ffbf7a7
• finagle-core: The default failure accrual policy has been changed from one
  which uses only consecutive failures to a hybrid model which uses both
  success rate over a window and consecutive failures. Previously this was
  changeable via toggle. The toggle has been removed, and the hybrid version
  has been made the default. 6f85c56e
• finagle-http: Rename request_stream_duration_ms to stream/request/duration_ms and
  response_stream_duration_ms to stream/response/duration_ms. The stats will be
  populated when isChunked is set to true in the request and response respectively.
  d9b69bdc
• finagle-http2: Disable ping-based failure detector in HTTP/2 client as it seems to do
  more harm than good. ea5b0c77
• finagle-http2: Frame logging is now disabled by default for clients. To enable,
  use the c.t.f.http2.param.FrameLogging.Enabled Stack Param. For example:
  Http.client.configured(FrameLogging.Enabled). 0b2ec201
• finagle-netty4: When using a Netty LocalChannel, the value of the BackPressure
  stack param is effectively changed to backPressureDisabled so that other functionality
  (e.g. SSL/TLS) works as expected. 3a8e5c19
• finagle-netty4: finagle/netty/pooling/used now includes the size of the buffers in the
  thread-local caches. 824596f0
• finagle-core: Stats and retry modules use a ResponseClassifier to give hints
  for how to handle failure (e.g., Is this a success or is it a failure? If
  it's a failure, may I retry the request?). The stats module increments a
  success counter for successes, and increments a failure counter for failures.
  But there isn't a way to tell the stats module to just do nothing. And, this
  is exactly what the stats module should do (nothing) in the case of ignorable
  failures (e.g. backup request cancellations). To represent these cases, we
  introduce a new ResponseClass: Ignorable. 256b79b8

Bug Fixes

• finagle-core: UsingSslSessionInfo would fail to be constructed properly when
  SSLSession.getLocalCertificates returns 'null'. 8d984963
• finagle-http: Finagle now properly sets the Transport.peerCertificate local context
  when using HTTP/2. a661fef4
• finagle-http: c.t.f.http.collection.RecordSchema.Record is now thread-safe.
  4e343f0e
• finagle-zipkin-core: Fix a race condition which could cause a span to get logged
  missing some annotations. 53901a28
• finagle-mysql: Don't log c.t.f.ChannelClosedException when rolling back a transaction
  fails. 29cfffe6

Breaking API Changes

• finagle-core: The exceptions c.t.f.SslHandshakeException and
  c.t.f.SslHostVerificationException were no longer used and have
  been removed. 2a53531d
• finagle-mysql: The structure of c.t.f.mysql.Request has changed. It is now based on
  a higher level c.t.f.mysql.ProtocolMessage and the cmd field must contain a value.
  Additionally, the synthetic Command.COM_NO_OP has been removed, as due to the
  restructuring it was no longer necessary. d6e4042f
• finagle-mysql: Uses of the abbreivation 'cap' have been renamed to the full
  word: 'capabilities', including for the baseCapabilities of Capability.
  4c57afda

Deprecations

• finagle-http: Removed deprecated response_size in Finagle Http stats. This is a duplicate stat
  of response_payload_bytes. 1286c438

No Changes

New Features

• finagle-http: Add two new methods to com.twitter.finagle.http.MediaType,
  MediaType#typeEquals for checking if two media types have the same type and
  subtype, ignoring their charset, and MediaType#addUtf8Charset for easily
  setting a utf-8 charset. ec0953f1

Bug Fixes

• finagle-http: Ensure server returns 400 Bad Request when
  non-ASCII characters are present in the HTTP request URI path. a7dae7ea

Runtime Behavior Changes

• finagle-core: Deterministic aperture (d-aperture) load balancers no longer export
  "loadband" scoped metrics: "widen", "narrow", "offered_load_ema". These were not
  necessary as d-aperture does not change the aperture size at runtime. 20029ac5
• finagle-core: Request logging now defaults to disabled. Enable it by configuring the
  RequestLogger Stack parameter on your Client or Server. ee9cb4ec
• finagle-core: Subtree binding failures in NameTree.Union's are ignored in the
  final binding result. 2fde4d2d

Breaking API Changes

• finagle-core: The c.t.f.client.EndpointerModule and c.t.f.pushsession.PushStackClient public
  and protected APIs have been changed to use the abstract java.net.SocketAddress instead of the
  concrete java.net.InetSocketAddress as relying on the concrete implementation was not
  necessary. 77a3cdfd
• finagle-http: For Finagle HTTP clients, the withMaxRequestSize(size) API
  method has been removed. For Finagle HTTP servers, the
  withMaxResponseSize(size) method has been removed. The underlying Stack
  params which are set by these methods are respectively HTTP server and HTTP
  client side params only. Using these removed methods had no effect on the
  setup of Finagle HTTP clients and servers. 5eb3ae24
• finagle-mysql: HandshakeResponse has been removed from finagle-mysql's public
  API. It is expected that users of the library are relying entirely on
  finagle-mysql for handshaking. f0ab09a6

19.4.0

New Features

• finagle-core: Make maxDepth in Namer configurable. 03cc3197
  • namerMaxDepth in Namer now configurable through a global flag (namerMaxDepth)
• finagle-core: The newly renamed SslSessionInfo is now public. It is
  intended for providing information about a connection's SSL/TLS session.
  811fe004
• finagle-core: Added the c.t.finagle.DtabFlags trait which defines a Flag and function for
  appending to the "base" c.t.finagle.Dtab delegation table. 675630df
• finagle-http: Finagle HTTP implementation now supports trailing headers (trailers). Use
  c.t.f.http.Message.trailers to access trailing headers on a fully-buffered message
  (isChunked == false) or c.t.f.http.Message.chunkReader on a message with chunked payload
  (isChunked == true). 351c43c1
• finagle-http,thriftmux: Added tracing annotations to backup requests. 48f54e82
  • Binary annotation "srv/backup_request_processing", when servers are processing backup requests.
• finagle-http: Added new server metrics to keep track of inbound requests that are rejected due to
  their headers containing invalid characters (as seen by RFC-7230): rejected_invalid_header_names
  and rejected_invalid_header_values. 41bd061a
• finagle-http: Added stats of the duration in milliseconds of request/response streams:
  request_stream_duration_ms and response_stream_duration_ms. They are enabled by using
  .withHttpStats on Http.Client and Http.Server 916f4a26
• finagle-mysql: A new toggle, "com.twitter.finagle.mysql.IncludeHandshakeInServiceAcquisition", has
  been added. Turning on this toggle will move MySQL session establishment (connection phase) to be
  part of service acqusition. fe4d8919

Runtime Behavior Changes

• finagle-core: Client-side nacking admission control now defaults on. See the documentation
  on c.t.f.filter.NackAdmissionFilter for details. This can be disabled by setting the
  global flag, com.twitter.finagle.client.useNackAdmissionFilter, to false.
  aa36f56b
• finagle-core: LatencyCompensation now applies to service acquisition. 1ec020a5
• finagle-http: HTTP headers validation on the outbound path is now in compliance with RFC7230.
  5b2e9f95
• finagle-netty4: Netty's reference leak tracking now defaults to disabled.
  Set the flag com.twitter.finagle.netty4.trackReferenceLeaks to true to enable.
  f63d7f7a

Breaking API Changes

• finagle: Dropped a dependency on Netty 3:

  • finagle-netty3 sub-project has been removed

  • finagle-http-cookie sub-project has been removed

  • c.t.f.http.Cookie no longer takes Netty's DefaultCookie in the constructor
    03c773a5

• finagle-core: The peerCertificate methods of c.t.f.t.TransportContext and
  c.t.f.p.PushChannelHandle have been replaced with the more robust
  sslSessionInfo. Users looking for just the functional equivalence of
  peerCertificate can use sslSessionInfo.peerCertificates.headOption.
  dc4bfbcf

• finagle-core: The com.twitter.finagle.core.UseClientNackAdmissionFilter toggle
  has been replaced by a global flag, com.twitter.finagle.client.useNackAdmissionFilter.
  aa36f56b

• finagle-thrift: Allow users to specify stringLengthLimit and containerLengthLimit 233150a9

  • method parameter readLength in com.twitter.finagle.thrift.Protocols#binaryFactory renamed to stringLengthLimit to reflect usage
  • method parameter containerLengthLimit added to com.twitter.finagle.thrift.Protocols#binaryFactory

New Features

• finagle-core: Added tracing annotations to backup requests. 5201f623
  • Timestamped annotation "Client Backup Request Issued"
  • Timestamped annotation "Client Backup Request Won" or "Client Backup Request Lost"
  • Binary annotation "clnt/backup_request_threshold_ms", with the current value of the
    latency threshold, in milliseconds
  • Binary annotation "clnt/backup_request_span_id", with the span id of the backup request

Breaking API Changes

• finagle-core: Deprecated multi-param legacy tls methods have been removed in
  c.t.f.param.ServerTransportParams and c.t.f.builder.ServerBuilder. Users should migrate to
  using the tls(SslServerConfiguration) method instead. ca646bd8

Runtime Behavior Changes

• finagle-core: The tracing annotations from MkJvmFilter have been enhanced. 0586f657
  • Timestamped annotations "GC Start" and "GC End" for each garbage collection event
    that occurred during the request.
  • Binary annotation "jvm/gc_count", with the total number of garbage collection events
    that occurred during the request.
  • Binary annotation "jvm/gc_ms", with the total milliseconds of garbage collection events
    that occurred during the request.

New Features

• finagle-core: Added gauge is_marked_dead as an indicator of whether the host is marked
  as dead(1) or not(0) in FailFastFactory. 068a15e6
• finagle-core: KeyCredentials.CertsAndKey has been added as an option for
  c.t.f.ssl.KeyCredentials for when the certificate and certificate chain are
  contained within the same file. b4a9e8cd
• finagle-thriftmux: Additional information is now annotated in traces for clients
  using Scrooge generated Thrift bindings. c69a22f8, 32d9b56b,
  6283c6ce.
  This includes:
  • RPC method name
  • Request serialization time, in nanoseconds
  • Request deserialization time, in nanoseconds
  • Response serialization time, in nanoseconds
  • Response deserialization time, in nanoseconds

Breaking API Changes

• finagle-http: Removed Http.Client.withCompressionLevel because it wasn't doing anything.
  To migrate your client, simply remove the configuration--it had absolutely no effect.
  87944371

• finagle-http: c.t.f.dispatch.ExpiringServerDispatcher was dead code. We removed it.
  ae0571c9

• finagle-thrift: Removed newIface and newServiceIface methods from
  c.t.f.thrift.ThriftRichClient.MultiplexedThriftClient, which are deprecated in November 2017.
  773b6e57

• finagle-thrift: Removed deprecated APIs located in Thrift.scala:
  1. c.t.f.Thrift.Client.stats => use c.t.f.Thrift.Client.clientParam.clientStats
  2. c.t.f.Thrift.withProtocolFactory => use c.t.f.Thrift.client.withProtocolFactory
  3. c.t.f.Thrift.withClientId => usec.t.f.Thrift.client.withClientId
  4. c.t.f.Thrift.Server.serverLabel => use c.t.f.Thrift.Server.serverParam.serviceName
  5. c.t.f.Thrift.Server.serverStats => use c.t.f.Thrift.Server.serverParam.serverStats
  6. c.t.f.Thrift.Server.maxThriftBufferSize => use c.t.f.Thrift.Server.serverParam.maxThriftBufferSize
  c6eb2020

• finagle-thrift: c.t.f.thrift.ThriftServiceIface.Filterable is removed, use
  c.t.f.thrift.service.Filterable instead. 23affacc

• finagle-thrift: c.t.f.thrift.ThriftServiceIface is removed, use
  c.t.f.thrift.service.ThriftServicePerEndpoint instead. 23affacc

• finagle-thriftmux: Removed deprecated APIs located in ThriftMux.scala:
  1. c.t.f.ThriftMux.Client.stats => use c.t.f.ThriftMux.Clien.clientParam.clientStats
  2. c.t.f.ThriftMux.Server.serverLabel => use c.t.f.ThriftMux.Server.serverParam.serviceName
  3. c.t.f.ThriftMux.Server.serverStats => use c.t.f.ThriftMux.Server.serverParam.serverStats
  4. c.t.f.ThriftMux.Server.maxThriftBufferSize => use c.t.f.ThriftMux.Server.serverParam.maxThriftBufferSize
  c6eb2020

• finagle-thriftmux: ThriftMux.Client.pushMuxer is removed. Use ThriftMux.Client.standardMuxer
  instead. 90333b1a

• finagle-thriftmux: ThriftMux.serverMuxer is removed. Use ThriftMux.Server.defaultMuxer
  instead. 90333b1a

• finagle-base-http: Removed the c.t.f.http.Statuses java helper, which was deprecated two years
  ago in favor of using c.t.f.http.Status directly. 75a4a209

• finagle-base-http: Removed the c.t.f.http.Versions java helper, which was deprecated two years
  ago in favor of using c.t.f.http.Version directly. f191f1db

• finagle-base-http: Removed the c.t.f.http.Methods java helper, which was deprecated two years
  ago in favor of using c.t.f.http.Method directly. ccf10dbc

• finagle-http: c.t.f.http.Response.Ok was removed. Use just Response() or Response.Proxy
  if you need to mock it. d93bb1c9

• finagle-core: Drv.Aliased and Drv.newVose are now private, please
  construct a Drv instance using Drv.apply or Drv.fromWeights.
  9c810dd3

• finagle-core: c.t.f.BackupRequestLost is now removed. Please use c.t.f.Failure.ignorable
  instead. 02d3d524

Bug Fixes

• finagle-http: Fix for a bug where HTTP/2 clients could retry requests that had a chunked
  body even if the request body was consumed. b031e757
• finagle-http: Fix for a bug where HTTP clients could assume connections are reusable, despite
  having streaming requests in flight. 88a2d0ba

Runtime Behavior Changes

• finagle-core: Faster Filters. Removes unnecessary Service.rescue proxies from
  the intermediate andThen-ed Filters. Previously in rare cases you might have seen
  a raw Exception not wrapped in a Future if the Filter threw. These will now
  consistently be lifted into a Future.exception. a2ddc727
• finagle-core: MethodBuilder metrics filtering updated to now report rolled-up
  logical failures. 6e3bf33f
• finagle-http: Disabling Netty3 cookies in favor of Netty4 cookies. fccd92c6
• finagle-http: Removed the debug metrics http/cookie/dropped_samesites and
  http/cookie/flagless_samesites. 2de928ce

Deprecations

• finagle-core: Multi-param legacy tls methods have been deprecated in
  c.t.f.param.ServerTransportParams and c.t.f.builder.ServerBuilder. Users should migrate
  to using the tls(SslServerConfiguration) method instead. fbfc6d1a
• finagle-core: $client.withSession.maxIdleTime is now deprecated; use
  $client.withSessionPool.ttl instead to set the maximum allowed duration a connection may be
  cached for. 0f060e37
• finagle-serversets: c.t.f.zookeeper.ZkResolver has been deprecated in favor
  of c.t.f.serverset2.Zk2Resolver. 9878a9ec

New Features

• finagle-core: c.t.f.s.StackBasedServer has been changed to extend the
  c.t.f.Stack.Transformable trait. This brings StackBasedServer into parity
  with c.t.f.c.StackBasedClient, which already extends the
  Stack.Transformable trait. 9f637b5e
• finagle-http: HttpMuxer propagates the close signal to the underlying handlers.
  6475680d

Breaking API Changes

• finagle-core: The deprecated c.t.f.b.ServerBuilder.stack method which takes a function
  has been removed. Uses of this method should be changed to use the c.t.f.b.ServerBuilder.stack
  method which takes a c.t.f.s.StackBasedServer instead. a05e5e7b
• finagle-core: The type of c.t.f.b.ServerConfig.nilServer has been changed from
  Server[Req, Rep] to StackBasedServer[Req, Rep]. 4be953d4
• finagle-core: The access level of the c.t.f.b.ServerBuilder.copy method has changed
  from protected to private. 4be953d4
• finagle-core: The bridge type c.t.f.b.Server has been removed. Users should
  change to use c.t.f.ListeningServer instead. Uses of the previously
  deprecated Server.localAddress should use ListeningServer.boundAddress
  instead. eb66ee71
• finagle-core: The deprecated c.t.f.t.Transport.localAddress and
  c.t.f.t.Transport.remoteAddress methods are now final and can no longer
  be extended. Users should migrate to the respective c.t.f.t.TransportContext
  methods. b85f43a0
• finagle-thrift: The c.t.f.t.ThriftRichClient.protocolFactory and
  c.t.f.t.ThriftRichServer.protocolFactory methods have been removed. Users should
  switch to using ThriftRichClient.clientParam.protocolFactory and
  ThriftRichServer.serverParam.protocolFactory instead. In addition, implementations
  of the protocolFactory method have been removed from the concrete c.t.f.Thrift
  and c.t.f.ThriftMux client and server. e33baf82

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. 8f5774cb
• finagle-http: Compression level of 0 was failing on the server-side when speaking h2c.
  Updated so that it can handle a request properly. 5f96fcb2
• finagle-thriftmux: A Java compatibility issue for users trying to call withOpportunisticTls
  on ThriftMux clients and servers has been fixed. e57d2a91

Runtime Behavior Changes

• finagle-core: ServiceFactory.const propagates the close from the ServiceFactory
  to the underlying service, instead of ignoring it. 6475680d

18.12.0

New Features

• finagle-redis: Add support for the new stream API released in Redis 5.0. ba578c14
• finagle-core: Add Java compatibility for c.t.f.Filter.TypeAgnostic.Identity
  via c.t.f.Filter.typeAgnosticIdentity(). cff9aedd
• finagle-core: Add Java compatibility for c.t.f.Name through Names.
  30a8000c
• finagle-core: Introduce a StackServer.withStack overload that
  makes modifying the existing Stack easier when using method chaining.
  f1a980cf
• finagle-thrift: Add c.t.finagle.thrift.MethodMetadata which provides a LocalContext Key
  for setting information about the current Thrift method and an accessor for retrieving
  the currently set value. 7b22e4ef
• finagle-thrift: Update c.t.finagle.thrift.MethodMetadata to provide an
  asCurrent method to set the current c.t.finagle.thrift.MethodMetadata in the
  LocalContext. f46e1f77

Breaking API Changes

• finagle-core: The c.t.u.Closable trait has been removed from
  c.t.f.t.TransportContext, as well as the close and onclose methods. Uses of
  these methods within TransportContext should be changed to use the corresponding
  methods on c.t.f.t.Transport instead. b8b850bb
• finagle-core: The deprecated c.t.f.t.Transport.peerCertificate method on the Transport class
  (not the Transport.peerCertificate Finagle context) has been removed. Uses of this
  method should be changed to use c.t.f.t.TransportContext.peerCertificate instead.
  ab0432b4
• finagle-core: The deprecated c.t.f.t.TransportContext.status method has been removed
  from TransportContext. Uses of this method should be changed to use
  c.t.f.t.Transport.status instead. fd97536f
• finagle-mysql: c.t.f.m.Charset has been renamed to c.t.f.m.MysqlCharset to resolve
  any ambiguity between it and the Charset Stack parameter. 05354cd5
• finagle-mysql: All Stack params (Charset, Credentials, Database, FoundRows,
  MaxConcurrentPrepareStatements, UnsignedColumns) have been moved to the
  com.twitter.finagle.mysql.param namespace. d30c5549
• finagle-mysql: The deprecated c.t.f.m.Client.apply(factory, statsReceiver) method
  has been removed. 17747e1a
• finagle-mysql: The c.t.f.m.Handshake class and companion object have been made
  private. 20c8d50f
• finagle-http: Rename the toggle 'c.t.f.h.UseH2CClients' to 'c.t.f.h.UseH2CClients2'.
  43c0b69c

Runtime Behavior Changes

• finagle: Upgrade to Netty 4.1.31.Final and netty-tcnative 2.0.19.Final. 8e0f4b86
• finagle-base-http: The DefaultHeaderMap will replace obs-fold ( CRLF 1*(SP/HTAB) ) in
  inserted header values. 51c4f789

New Features

• finagle-base-http: Add Message.httpDateFormat(millis) to format the epoch millis into
  an RFC 7231 formatted String representation. eb9bec0e
• finagle-core: Introduce an StackClient.withStack overload that
  makes modifying the existing Stack easier when using method chaining.
  8f69e833
• finagle-mysql: Introduce session to be able to perform multiple operations that require
  session state on a guaranteed single connection. a06f7d67
• finagle-netty4: When using the native epoll transport, finagle now publishes the TCP window size
  and number of retransmits based on the tcpInfo provided by from the channel. These stats are
  published with a debug verbosity level. 16071088
• finagle-http: HTTP clients and servers now accept fixedLengthStreamedAfter param in their
  withStreaming configuration (default: 5 MB when streaming is enabled). This new parameter
  controls the limit after which Finagle will stop aggregating messages with known Content-Length
  (payload will be available at .content) and switch into a streaming mode (payload will be
  available at .reader). Note messages with Transfer-Encoding: chunked never aggregated.
  842e5e1a

Breaking API Changes

• finagle-http: c.t.f.http.param.MaxChunkSize has been removed. There is no good reason to
  configure it with anything but Int.MaxValue (unlimited). 990c8650
• finagle-exp: Update DarkTrafficFilter#handleFailedInvocation to accept the request type
  for more fidelity in handling the failure. b247f941

Runtime Behavior Changes

• finagle-http: Unset maxChunkSize limit in Netty HTTP codecs. Now both clients and servers
  emit all available data as a single chunk so we can put it into use quicker.
  990c8650
• finagle-http: Streaming clients (withStreaming(true)) now aggregate inbound messages with known
  Content-Length if their payloads are less than 5mb (8k before). Use withStreaming(true, 32.kb)
  to override it with a different value. 24271b29
• finagle-http2: HTTP/2 servers perform a more graceful shutdown where an initial
  GOAWAY is sent with the maximum possible stream id and waits for either the client
  to hang up or for the close deadline, at which time a second GOAWAY is sent with
  the true last processed stream and the connection is then closed.
  93fee499

Deprecations

• finagle-core: Deprecate
  EndpointerStackClient.transformed(Stack[ServiceFactory[Req, Rep]] => Stack[ServiceFactory[Req, Rep]])
  in favor of the withStack variant. 8f69e833

Deprecations

• finagle-core: Deprecation warnings have been removed from the 'status', 'onClose',
  and 'close' methods on c.t.f.t.Transport, and added to the corresponding methods
  on c.t.f.t.TransportContext. 9ae6d978

Runtime Behavior Changes

• finagle-netty3: Implementations for 'status', 'onClose', and 'close' methods have
  been moved from c.t.f.n.t.ChannelTransportContext to c.t.f.n.t.ChannelTransport.
  9ae6d978

18.8.0

New Features

• finagle-core: Introducing the new c.t.f.tracing.Tracing API for more efficient tracing
  (dramatically reduces the number of context lookups; see scaladoc for c.t.f.tracing.Trace).
  547cd864

• finagle-core: c.t.f.tracing.Trace facade API now provides forwarding record methods for
  all kinds of annotations and is a preffered way of recording traces. 50c00d88

• finagle-thriftmux: Promote the push-based ThriftMux implementation out of experimental
  status.eedd1fd8

Breaking API Changes

• finagle-base-http: c.t.f.http.cookie.exp.supportSameSiteCodec has been moved out of the
  exp package to c.t.f.http.cookie.supportSameSiteCodec. 5e5ea390

• finagle-core: Parameter-less annotation classes (c.t.f.tracing.Annotation) have been
  promoted to objects for efficiency reasons. 50c00d88

• finagle-core: c.t.f.tracing.Trace.record(Record) now accepts the record argument by
  value (previously by name). 33841d21

• finagle-core: c.t.f.Failure.{Restartable, Interrupted, Ignorable, DeadlineExceeded, Wrapped, Rejected, NonRetryable} are deprecated in favor of the c.t.f.FailureFlags
  analogs. 0e0c7b43

• finagle-core: c.t.f.Leaf and c.t.f.Node are now private; use Stack.leaf and
  Stack.node instead. cc49ee83

• finagle-core: Marked transform in com.twitter.finagle.Stack as protected. It is too
  powerful and unnecessary for users, and should be for implementor use only. 99479f32

• finagle-mysql: c.t.f.mysql.CanBeParameter's implicit conversions timestampCanBeParameter,
  sqlDateCanBeParameter, and javaDateCanBeParameter have been consolidated into a single
  implicit, dateCanBeParameter. b486772d

Bug Fixes

• finagle-http2: Fixed a race condition caused by c.t.f.http.transport.StreamTransports being
  closed, but that status not being reflected right away, causing a second request to fail.
  68f1035f

Runtime Behavior Changes

• finagle-core: c.t.f.tracing.Trace API is no longer guarding Trace.record calls behind
  Trace.isActivelyTracing. Add Trace.isActivelyTracing guards on the call sites if
  materializing tracing annotations is a performance concern. 33841d21

• finagle-mysql: Clients will now issue a ROLLBACK each time a service is checked back
  into the connection pool. This can be disabled via Mysql.Client.withNoRollback.
  e3221597

• finagle-thriftmux: The push-based server muxer is now the default. In both synthetic tests
  and production it has shown signifcant performance benefits and is simpler to maintain.
  735a6bae

• finagle-mysql: Remove deprecated TimestampValue.apply(Timestamp) and
  TimestampValue.unapply(value) methods. Use TimestampValue.apply(TimeZone, TimeZone)
  instead. e01f02f5

Deprecations

• finagle-mux: The pull based mux implementation, c.t.f.Mux, has been deprecated in favor of
  the push-based mux implementation, c.t.f.pushsession.MuxPush. 735a6bae

New Features

• finagle-core: There is now an implicit instance for Finagle's default timer:
  DefaultTimer.Implicit. 64963bd8

• finagle-core: Introduce new command-line flag c.t.f.tracing.enabled to entirely
  disable/enable tracing for a given process (default: true). 5a5ceb63

• finagle-mysql: com.twitter.util.Time can now be used with
  PreparedStatements without converting the ctu.Time to a java.sql.Timestamp.
  bbca48c7

• finagle-stats: Adds a lint rule to detect when metrics with colliding names are used.
  26a2c3bd

Breaking API Changes

• finagle-core: c.t.f.dispatch.ClientDispatcher.wrapWriteException has been turned from a
  partial function instance into a static total function. 9a3c9070

• finagle-mux: ClientDiscardedRequestException now extends FailureFlags and is no longer
  a case class. fe8c6496

Runtime Behavior Changes

• finagle-core: Server-side rejections from c.t.f.filter.RequestSempahoreFilter.module are now
  captured by c.t.f.service.StatsFilter. They will roll up under "/failures",
  "/failures/rejected", and "/failures/restartable" in stats. 3b755c8a

• finagle-core: c.t.f.tracing.Trace.tracers now returns only distinct tracers stored in
  the local context (returned all tracers before). b96bb137

• finagle-http: HTTP param decoding is no longer truncated to 1024 params.
  24662bea

• finagle-mux: When mux propagates an interrupt started by BackupRequestFilter over the
  network, the FailureFlags.Ignorable status is propagated with it. fe8c6496

Runtime Behavior Changes

• finagle-core: By default, the deterministic aperture load balancer doesn't expand
  based on the loadband. This is because the loadband is influenced by a degree of
  randomness, and this breaks the deterministic part of deterministic aperture and
  can lead to aggressive banding on backends. 3d84e297

• finagle-http2: Unprocessed streams are retryable in case of GOAWAY.
  2c89cb9e

New Features

• finagle-core: Add PropagateDeadlines Stack.Param to TimeoutFilter for
  disabling propagation of deadlines to outbound requests.
  8041fbb9

• finagle-core: Add toString implementations to c.t.finagle.Service and
  c.t.finagle.Filter. Update in Filter#andThen composition to expose a
  useful toString for composed Filters and a composed Service (a Filter chain
  with a terminal Service or ServiceFactory).

  The default implementation for Filter and Service is getClass.getName. When
  composing filters, the andThen composition method correctly tracks the composed
  parts to produce a useful toString, e.g.,

  package com.foo

  import com.twitter.finagle.{Filter, Service}
  import com.twitter.util.Future

  class MyFilter1 extends Filter[Int, Int, Int, Int] {
     def apply(request: Int, service: Service[Int, Int]): Future[Int] = ???
  }

  ...

  package com.foo

  import com.twitter.finagle.{Filter, Service}
  import com.twitter.util.Future

  class MyFilter2 extends Filter[Int, Int, Int, Int] {
    def apply(request: Int, service: Service[Int, Int]): Future[Int] = ???
  }

  val filters = (new MyFilter1).andThen(new MyFilter2)

filters.toString would emit the String "com.foo.MyFilter1.andThen(com.foo.MyFilter2)"

If a Service (or ServiceFactory) were then added:

  import com.twitter.finagle.{Filter, Service}
  import com.twitter.finagle.service.ConstantService
  import com.twitter.util.Future

  ...

  val svc: Service[Int, Int] = filters.andThen(new ConstantService[Int, Int](Future.value(2)))

Then, svc.toString would thus return the String:
"com.foo.MyFilter1.andThen(com.foo.MyFilter2).andThen(com.twitter.finagle.service.ConstantService(ConstFuture(2)))"

Filter implementations are permitted to override their toString implementations which would
replace the default of getClass.getName. 25474da1

• finagle-core: Make Filter.TypeAgnostic an abstract class for Java usability.
  6534e459

• finagle-core: c.t.f.filter.NackAdmissionFilter is now public. 1855566d

• finagle-core: Extended c.t.f.ssl.KeyCredentials and c.t.f.ssl.TrustCredentials to work
  with javax.net.ssl.KeyManagerFactory and javax.net.ssl.TrustManagerFactory respectively.
  c863ca0b

Breaking API Changes

• finagle-core: Rename DeadlineFilter.Param(maxRejectFraction) to
  DeadlineFilter.MaxRejectFraction(maxRejectFraction) to reduce confusion
  when adding additional params.
  cb6975af

Bug Fixes

• finagle-http2: StreamTransportFactory now marks itself as dead/closed when it runs out of
  HTTP/2 stream IDs instead of stalling. This allows the connection to be closed/reestablished in
  accordance with the spec c5554673

• finagle-netty4: SslServerSessionVerifier is now supplied with the proper peer address
  rather than Address.failing. 263e9786

• finagle-thrift/thriftmux: Disabled client side per-endpoint stats by default for client
  ServicePerEndpoint. It can be set via c.t.f.thrift.RichClientParam or a with-method
  as Thrift{Mux}.client.withPerEndpointStats. 0f1ff3eb

• finagle-netty4: Avoid NoClassDefFoundError if netty-transport-native-epoll is not available
  on the classpath. 940809af

New Features

• finagle-base-http: Added ability to add SameSite attribute to Cookies to
  comply with https://tools.ietf.org/html/draft-west-first-party-cookies-07.
  The attribute may be set in the constructor via the c.t.f.http.Cookie
sameSite param or via the c.t.f.http.Cookie.sameSite method.

  • Pass SameSite.Lax to the Cookie to add the "Lax" attribute.
  • Pass SameSite.Strict to the Cookie to add the "Strict" attribute.
    4b0a58b0

• finagle-base-http: Introduced an API to extract query string params from a
  c.t.f.http.Request, c.t.f.http.Uri.fromRequest and c.t.f.http.Uri#params.
  0dd0a425

• finagle-mysql: Added APIs to Row which simplify the common access pattern.
  For example, Row.stringOrNull(columnName: String): String and
  Row.getString(columnName: String): Option[String].
  f3676d31, f3676d31

• finagle-mysql: Added read and modify APIs to c.t.f.mysql.Client and
  c.t.f.mysql.PreparedStatement for that return the specific type of
  Result for those operations, ResultSet and OK respectively.
  2f3650cf

• finagle-serversets: Zk2Session's AsyncSemaphore which controls the maximum
  concurrent Zk operations is configurable (GlobalFlag c.t.f.serverset2.zkConcurrentOperations).
  [3160a815](https://github.com/twitter/finagle/commit/3160a815c2552773a67d834841b029dca5ba0122)

• finagle-mysql: Address CursoredStatement usability from Java via
  CursoredStatement.asJava(). Through this, you can use the API with
  varargs and Java 8 lambdas. f67978aa

• finagle-toggle: Improved Java compatiblity for ToggleMap and Toggle. 16dbe170

• finagle-toggle: StandardToggleMap.apply and StandardToggleMap.registeredLibraries now
  use ToggleMap.Mutable to better support mutating the underlying mutable ToggleMap.
  8b136a22

Breaking API Changes

• finagle-mux: With the introduction of the push-based mux client, we've
  removed the need for the optimized c.t.f.Mux.Netty4RefCountingControl
  MuxImpl, which has been removed. 35980463

• finagle-mysql: c.t.f.mysql.Client.ping now returns a Future[Unit]
  instead of the broad Future[Result] ADT. 2f3650cf

• finagle-toggle: Changed ToggleMap.Mutable from a trait to an abstract class, and
  ToggleMap.Proxy no longer extends ToggleMap, but now has a self-type that conforms to
  ToggleMap instead. 16dbe170

Runtime Behavior Changes

• finagle-core: Add c.t.f.SslException to better model exceptions related to SSL/TLS.
  The c.t.f.ChannelException.apply method will now wrap javax.net.ssl.SSLExceptions in
  c.t.f.SslException. 955a0b3e

• finagle-core: MethodBuilder metrics now include failures.
  f58ab46f, f58ab46f

• finagle-http: ServerAdmissionControl is circumvented for HTTP requests that have
  a body unless the request contains the header 'finagle-http-retryable-request' since
  it cannot be known whether the client can actually retry them, potentially resulting
  in depressed success rates during periods of throttling. 4377f02a

• finagle-http2: Clients and servers no longer attempt a cleartext upgrade if the
  first request of the HTTP/1.1 session has a body. bf09dd4c

• finagle-thriftmux: The push-based client muxer is now the default muxer implementation.
  The push-based muxer has better performance and a simpler architecture. cc333151

• finagle-toggle: ToggleMap.Proxy#underlying is now public, and ToggleMap.Proxy
  participates in ToggleMap.components. 8b136a22

Bug Fixes

• finagle-base-http: Concurrent modification of the c.t.f.http.DefaultHeaderMap could
  result in an infinite loop due to HashMap corruption. Access is now synchronized to avoid
  the infinite loop. aa73d24d

• finagle-core: FailureFlags that have their flags set modified will now
  retain the original stack trace, suppressed Throwables, and cause when possible.
  f4543472

• finagle-memcached: Added the missing support for partial success for the batch
  operations in the new PartitioningService based Memcached client. 970af633

• finagle-thrift: Removed copied libthrift files. 9deb18b4

• finagle-thrift/thriftmux: Server side per-endpoint statsFilter by default is disabled now.
  It can be set via c.t.f.thrift.RichServerParam or a with-method as
  Thrift{Mux}.server.withPerEndpointStats. 7b0281c5

New Features

• finagle-core: c.t.f.filter.NackAdmissionFilter can now be disabled via a with-method.
  $Protocol.client.withAdmissionControl.noNackAdmissionControl 323a20f4

• finagle-mysql: Exceptions now include the SQL that was being executed when possible.
  5a54f45d

• finagle-mysql: Address PreparedStatement usability from Java via
  PreparedStatement.asJava(). Through this, you can use the API with
  varargs and Java 8 lambdas. c5bd6b97

• finagle-mysql: Added support for Option\s to Parameter implicits. This
  allows for the natural represention of nullable columns with an Option
  where a None is treated as a null. 48f688d1

• finagle-netty4: Add 'tls/connections' gauge for Finagle on Netty 4 which tracks the number
  of open SSL/TLS connections per Finagle client or server.
  911a01ce

• finagle-redis: Support has been added for a number of new cluster commands
  introduced in Redis 3.0.0. 86b151bf

Bug Fixes

• finagle-mysql: Fix handling of interrupts during transactions. 1b9111eb

Breaking API Changes

• finagle-core: c.t.f.ssl.client.HostnameVerifier has been removed since it was using
  sun.security.util.HostnameChecker which is no longer accessible in JDK 9.
  1313d9ba

• finagle-thrift: Upgraded libthrift to 0.10.0, c.t.f.thrift.Protocols.TFinagleBinaryProtocol
  constructor now takes stringLengthLimit and containerLengthLimit, NO_LENGTH_LIMIT value
  changed from 0 to -1. 61c7a711

• finagle-thrift: Move "stateless" methods in c.t.finagle.thrift.ThriftRichClient
  to c.t.finagle.thrift.ThriftClient. Then mix the ThriftClient trait into the
  ThriftMux and Thrift Client companions to make it clearer that these stateless methods
  are not affected by the changing state of the configured client instance but are instead
  simply utility methods which convert or wrap the incoming argument. 7a175a98

• finagle-base-http: Removed deprecated c.t.f.Cookie.value_=; use c.t.f.Cookie.value
  instead. 4bdd261b

• finagle-base-http: Removed deprecated c.t.f.Cookie.domain_=; use c.t.f.Cookie.domain
  instead. 4bdd261b

• finagle-base-http: Removed deprecated c.t.f.Cookie.path_=; use c.t.f.Cookie.path
  instead. 4bdd261b

Runtime Behavior Changes

• finagle-core: Add minimum request threshold for successRateWithinDuration failure accrual.
  b6caf3dd

• finagle-core: c.t.f.filter.NackAdmissionFilter no longer takes effect when
  the client's request rate is too low to accurately update the EMA value or
  drop requests. 387d87d4

• finagle-core: SSL/TLS client hostname verification is no longer performed by
  c.t.f.ssl.client.HostnameVerifier. The same underlying library
  sun.security.util.HostnameChecker is used to perform the hostname verification.
  However it now occurs before the SSL/TLS handshake has been completed, and the
  exception on failure has changes from a c.t.f.SslHostVerificationException to a
  javax.net.ssl.CertificateException. 1313d9ba

• finagle-core: Closing c.t.f.NullServer is now a no-op. 36aac62c

• finagle-netty4: Netty ByteBuf leak tracking is enabled by default. 24690b13

Deprecations

• finagle-thrift: System property "-Dorg.apache.thrift.readLength" is deprecated. Use
  constructors to set read length limit for TBinaryProtocol.Factory and TCompactProtocol.Factory.
  61c7a711

New Features

• finagle-core: c.t.f.client.BackupRequestFilter.filterService for wrapping raw services in a
  c.t.f.client.BackupRequestFilter is now public. b227d988

• finagle-core: Introduce c.t.f.Stacks.EMPTY_PARAMS for getting an empty Param map from
  Java, and c.t.f.Stack.Params.plus for easily adding Params to a Param map from Java.
  43e0f007

Bug Fixes

• finagle-core: c.t.f.liveness.FailureAccrualFactory takes no action on c.t.f.Failure.Ignorable
  responses. 512894cf

• finagle-core: c.t.f.pool.WatermarkPool is resilient to multiple closes on a service instance.
  37c29e9e

• finagle-core: c.t.f.pool.CachingPool service wrapper instances are resilient to multiple closes.
  ce779ec7

• finagle-core: Requeue module now closes sessions it prevented from propagating up the stack.
  f5cdda14

• finagle-base-http: c.t.f.http.Netty4CookieCodec.encode now wraps Cookie values that would
  be wrapped in c.t.f.http.Netty3CookieCodec.encode. 78fdc9aa

• finagle-base-http: c.t.f.http.Cookie.maxAge returns c.t.f.http.Cookie.DefaultMaxAge
  (instead of null) if maxAge has been set to null or None in the copy constructor
  17a32d44.

• finagle-http: The HTTP client will not attempt to retry nacked requests with streaming
  bodies since it is likely that at least part of the body was already consumed and therefore
  it isn't safe to retry. a787955b

Breaking API Changes

• finagle-base-http: Removed c.t.f.http.Cookie.comment_, c.t.f.http.Cookie.comment_=,
  c.t.f.http.Cookie.commentUrl_, and c.t.f.http.Cookie.commentUrl_=. comment and commentUrl
  per RFC-6265. NOT FOUND: D137538

• finagle-base-http: Removed deprecated c.t.f.http.Cookie.isDiscard and
  c.t.f.http.Cookie.isDiscard_=, per RFC-6265. 0e03b630

• finagle-base-http: Removed deprecated c.t.f.http.Cookie.ports and
  c.t.f.http.Cookie.ports_=, per RFC-6265. 0469f5b1

• finagle-base-http: c.t.f.http.RequestBuilder has been moved to the finagle-http target
  and the implicit evidence, RequestConfig.Yes has been renamed to RequestBuilder.Valid.
  1632856c

• finagle-base-http: Removed deprecated c.t.f.Cookie.isSecure; use c.t.f.Cookie.secure
  instead. Removed deprecated c.t.f.Cookie.isSecure_=. 33d75b95

• finagle-base-http: Removed deprecated c.t.f.http.Cookie.version and
  c.t.f.http.Cookie.version_=, per RFC-6265. 6c9020cc

• finagle-core: c.t.f.pool.WatermarkPool was finalized. 37c29e9e

• finagle-core: c.t.finagle.ssl.Ssl and related classes have been
  removed. They were replaced as the primary way of using SSL/TLS
  within Finagle in release 6.44.0 (April 2017). Please migrate to using
  c.t.f.ssl.client.SslClientEngineFactory or
  c.t.f.ssl.server.SslServerEngineFactory instead. d10a42b8

• finagle-core: Removed newSslEngine and newFinagleSslEngine from
  ServerBuilder. Please implement a class which extends
  c.t.f.ssl.server.SslServerEngineFactory with the previously passed in
  function used as the implementation of the apply method. Then use the
  created engine factory with one of the tls methods instead.
  d10a42b8

• finagle-core: The deprecated c.t.f.loadbalancer.DefaultBalancerFactory has been removed.
  f6971d76

• finagle-exp: The deprecated c.t.f.exp.BackupRequestFilter has been removed. Please use
  c.t.f.client.BackupRequestFilter instead. 350d8821

• finagle-http: Removed the c.t.f.Http.Netty3Impl. Netty4 is now the only
  underlying HTTP implementation available. ef9fedb1

• finagle-zipkin-scribe: Renamed the finagle-zipkin module to finagle-zipkin-scribe, to
  better advertise that this is just the scribe implementation, instead of the default.
  c23ef398

New Features

• finagle-core: Add orElse to allow composition of FailureAccrualPolicys.
  8c1e718e

• finagle-core: c.t.f.http.MethodBuilder now exposes a method newService without a
  methodName to create a client. c.t.f.thriftmux.MethodBuilder now exposes a
  method servicePerEndpoint without a methodName to create a client. d8e010d6

• finagle-thriftmux: Expose the underlying configured client label in the
  c.t.finagle.thriftmux.MethodBuilder. 653e2696

Bug Fixes

• finagle-http2: http2 servers no longer leak ping bodies. 02841dfd

Deprecations

• finagle-core: c.t.finagle.ssl.Ssl and related classes have been
  deprecated. They were replaced as the primary way of using SSL/TLS
  within Finagle in release 6.44.0 (April 2017). Please migrate to using
  c.t.f.ssl.client.SslClientEngineFactory or
  c.t.f.ssl.server.SslServerEngineFactory instead. 0b8a2890

Breaking API Changes

• finagle-base-http: c.t.f.h.codec.HttpCodec has been moved to the finagle-http
  project. 350953ae

• finagle base-http: c.t.f.h.Request.multipart has been removed.
  Use c.t.f.h.exp.MultipartDecoder instead. b9d71e36

• finagle-http: Split the toggle 'c.t.f.h.UseH2C' into a client-side toggle and a
  server-side toggle, named 'c.t.f.h.UseH2CClients', and 'c.t.f.h.UseH2CServers',
  respectively. 0d960398

Runtime Behavior Changes

• finagle-core: Finagle clients with retry budgets or backoffs should no
  longer have infinite hash codes. 88e7bea9

New Features

• finagle-core: FailureDetector has a new method, onClose, which provides
  a Future that is satisfied when the FailureDetector marks a peer as Closed.
  PHAB_ID=D126840

• finagle-core: Introduce trace logging of requests as they flow through a
  Finagle client or server. These logs can be turned on at runtime by setting
  the "com.twitter.finagle.request.Logger" logger to trace level.
  PHAB_ID=D124352

• finagle-http2: HTTP/2 clients now expose the number of currently opened streams under
  the $client/streams gauge. PHAB_ID=D127238

• finagle-http2: HTTP/2 servers now expose the number of currently opened streams under
  the $server/streams gauge. PHAB_ID=D127667

• finagle-memcached: By default, the Memcached client now creates two connections
  to each endpoint, instead of 4. PHAB_ID=D119619

• finagle-redis: Add support for redis Geo Commands. PHAB_ID=D123167 based on the PR
  #628 written by Mura-Mi [https://github.com/Mura-Mi]

• finagle-thrift: Add c.t.f.thrift.service.ThriftServiceBuilder and
  c.t.f.thrift.service.ReqRepThriftServiceBuilder for backwards compatibility
  of creating higher-kinded method-per-endpoint clients. PHAB_ID=D127538

• finagle-core: c.t.f.http.MethodBuilder and c.t.f.thriftmux.MethodBuilder now
  expose idempotent and nonIdempotent methods, which can be used to configure
  retries and the sending of backup requests. PHAB_ID=D122087

Bug Fixes

• finagle-mysql: Fix a bug with transactions where an exception during a rollback
  could leave the connection with a partially committed transaction. PHAB_ID=D122771

• finagle-toggle: c.t.f.toggle.Toggles are independent; that is, applying the same value to
  two different toggles with the same fraction will produce independent true/false
  values. PHAB_ID=D128172

Runtime Behavior Changes

• finagle-core, finagle-netty4: When creating engines, SslClientEngineFactories now use
  SslClientEngineFactory.getHostString instead of SslClientEngineFactory.getHostname.
  This no longer performs an unnecessary reverse lookup when a hostname is not supplied
  as part of the SslClientConfiguration. PHAB_ID=D124369

• finagle-http2: Supplies a dependency on io.netty.netty-tcnative-boringssl-static,
  which adds support for ALPN, which is necessary for encrypted http/2. To use a
  different static ssl dependency, exclude the tcnative-boringssl dependency and
  manually depend on the one you want to use. PHAB_ID=D119555

Breaking API Changes

• finagle-base-http, finagle-http: Removed Apache Commons Lang dependency,
  org.apache.commons.lang3.time.FastDateFormat now is java.time.format.DateTimeFormatter.
  PHAB_ID=D121479

• finagle-base-http: c.t.f.http.Message.headerMap is now an abstract method.
  PHAB_ID=D120931

• finagle-core: c.t.f.ssl.server.SslServerSessionVerifier no longer uses the unauthenticated
  host information from SSLSession. PHAB_ID=D124815

• finagle-memcached: ConcurrentLoadBalancerFactory was removed and its behavior
  was replaced by a Stack.Param inside finagle-core's LoadBalancerFactory.
  PHAB_ID=D119394

• finagle-thrift, finagle-thriftmux: Remove ReqRep specific methods. Since the "ReqRep"
  builders are now subclasses of their non-"ReqRep" counterparts their is no longer a
  need to expose "ReqRep" specific methods. PHAB_ID=D123341

Deprecations

• finagle-exp: c.t.f.exp.BackupRequestFilter has been deprecated. Please use
  c.t.f.client.BackupRequestFilter instead. PHAB_ID=D122344

• finagle-http: c.t.f.http.Request.multipart has been deprecated.
  Use c.t.f.http.exp.MultipartDecoder instead. PHAB_ID=D126013