Packages

  • package root
    Definition Classes
    root
  • package com
    Definition Classes
    root
  • package twitter

    Start with com.twitter.finagle.

    Start with com.twitter.finagle.

    Definition Classes
    com
  • package finagle

    Finagle is an extensible RPC system.

    Finagle is an extensible RPC system.

    Services are represented by class com.twitter.finagle.Service. Clients make use of com.twitter.finagle.Service objects while servers implement them.

    Finagle contains a number of protocol implementations; each of these implement Client and/or com.twitter.finagle.Server. For example, Finagle's HTTP implementation, com.twitter.finagle.Http (in package finagle-http), exposes both.

    Thus a simple HTTP server is built like this:

    import com.twitter.finagle.{Http, Service}
import com.twitter.finagle.http.{Request, Response}
import com.twitter.util.{Await, Future}

val service = new Service[Request, Response] {
  def apply(req: Request): Future[Response] =
    Future.value(Response())
}
val server = Http.server.serve(":8080", service)
Await.ready(server)

    We first define a service to which requests are dispatched. In this case, the service returns immediately with a HTTP 200 OK response, and with no content.

    This service is then served via the Http protocol on TCP port 8080. Finally we wait for the server to stop serving.

    We can now query our web server:

    % curl -D - localhost:8080
HTTP/1.1 200 OK

    Building an HTTP client is also simple. (Note that type annotations are added for illustration.)

    import com.twitter.finagle.{Http, Service}
import com.twitter.finagle.http.{Request, Response}
import com.twitter.util.{Future, Return, Throw}

val client: Service[Request, Response] = Http.client.newService("localhost:8080")
val f: Future[Response] = client(Request()).respond {
  case Return(rep) =>
    printf("Got HTTP response %s\n", rep)
  case Throw(exc) =>
    printf("Got error %s\n", exc)
}

    Http.client.newService("localhost:8080") constructs a new com.twitter.finagle.Service instance connected to localhost TCP port 8080. We then issue a HTTP/1.1 GET request to URI "/". The service returns a com.twitter.util.Future representing the result of the operation. We listen to this future, printing an appropriate message when the response arrives.

    The Finagle homepage contains useful documentation and resources for using Finagle.

    Definition Classes
    twitter
  • object Memcached extends Client[Command, Response] with Server[Command, Response]

    Stack based Memcached client.

    Stack based Memcached client.

    For example, a default client can be built through:

    Definition Classes
    finagle
    Examples:

    1. val client = Memcached.newRichClient(dest)

      If you want to provide more finely tuned configurations:

      2. , 

    2. val client =
  Memcached.client
    .withEjectFailedHost(true)
    .withTransport.connectTimeout(100.milliseconds))
    .withRequestTimeout(10.seconds)
    .withSession.acquisitionTimeout(20.seconds)
    .newRichClient(dest, "memcached_client")
  • Client
  • Server

case class Server(stack: Stack[ServiceFactory[Command, Response]] = StackServer.newStack, params: Params = Server.params) extends StdStackServer[Command, Response, Server] with Product with Serializable

Ordering
  1. Alphabetic
  2. By Inheritance
Inherited
  1. Server
  2. Serializable
  3. Product
  4. Equals
  5. StdStackServer
  6. ListeningStackServer
  7. WithServerAdmissionControl
  8. WithServerSession
  9. WithServerTransport
  10. CommonParams
  11. StackServer
  12. StackBasedServer
  13. Transformable
  14. Parameterized
  15. Server
  16. AnyRef
  17. Any
  1. Hide All
  2. Show All
Visibility
  1. Public
  2. Protected

Instance Constructors

  1. new Server(stack: Stack[ServiceFactory[Command, Response]] = StackServer.newStack, params: Params = Server.params)

Type Members

  1. type Context = TransportContext

    The type of the transport's context.

    The type of the transport's context.

    Attributes
    protected
    Definition Classes
    Server → StdStackServer
  2. type In = Buf

    The type we write into the transport.

    The type we write into the transport.

    Attributes
    protected
    Definition Classes
    Server → StdStackServer
  3. type Out = Buf

    The type we read out of the transport.

    The type we read out of the transport.

    Attributes
    protected
    Definition Classes
    Server → StdStackServer

Value Members

  1. final def !=(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  2. final def ##: Int
    Definition Classes
    AnyRef → Any
  3. final def ==(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  4. final def addServerToRegistry(listenerName: String): Unit

    Export info about the listener type to the global registry.

    Export info about the listener type to the global registry.

    The information about its implementation can then be queried at runtime.

    Attributes
    protected
    Definition Classes
    ListeningStackServer
  5. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  6. def clone(): AnyRef
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.CloneNotSupportedException]) @native()
  7. def configured[P](psp: (P, Param[P])): Server

    Creates a new StackServer with parameter psp._1 and Stack Param type psp._2.

    Creates a new StackServer with parameter psp._1 and Stack Param type psp._2.

    Definition Classes
    Server → ListeningStackServer → StackServer → Parameterized
  8. def configured[P](p: P)(implicit arg0: Param[P]): Server

    Creates a new StackServer with parameter p.

    Creates a new StackServer with parameter p.

    Definition Classes
    ListeningStackServer → StackServer → Parameterized
  9. def configuredParams(newParams: Params): Server

    Creates a new StackServer with additional parameters newParams.

    Creates a new StackServer with additional parameters newParams.

    Definition Classes
    ListeningStackServer → StackServer → Parameterized
  10. def copy1(stack: Stack[ServiceFactory[Command, Response]] = this.stack, params: Params = this.params): Server

    A copy constructor in lieu of defining StackServer as a case class.

    A copy constructor in lieu of defining StackServer as a case class.

    Attributes
    protected
    Definition Classes
    Server → ListeningStackServer
  11. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  12. def finalize(): Unit
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.Throwable])
  13. final def getClass(): Class[_ <: AnyRef]
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  14. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  15. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  16. def newDispatcher(transport: Transport[In, Out] { type Context <: Server.this.Context }, service: Service[Command, Response]): Closable

    Defines a dispatcher, a function which binds a transport to a com.twitter.finagle.Service.

    Defines a dispatcher, a function which binds a transport to a com.twitter.finagle.Service. Together with a Listener, it forms the foundation of a finagle server. Concrete implementations are expected to specify this.

    Attributes
    protected
    Definition Classes
    Server → StdStackServer
    Note

    The dispatcher must be prepared to handle the situation where it receives an already-closed transport.

    See also

    com.twitter.finagle.dispatch.GenSerialServerDispatcher

  17. def newListener(): Listener[In, Out, TransportContext]

    Defines a typed com.twitter.finagle.server.Listener for this server.

    Defines a typed com.twitter.finagle.server.Listener for this server. Concrete StackServer implementations are expected to specify this.

    Attributes
    protected
    Definition Classes
    Server → StdStackServer
  18. final def newListeningServer(serviceFactory: ServiceFactory[Command, Response], addr: SocketAddress)(trackSession: (ClientConnection) => Unit): ListeningServer

    Constructs a new ListeningServer from the ServiceFactory.

    Constructs a new ListeningServer from the ServiceFactory. Each new session is passed to the trackSession function exactly once to facilitate connection resource management.

    Attributes
    protected
    Definition Classes
    StdStackServer → ListeningStackServer
  19. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  20. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  21. val params: Params

    The current parameter map used in this StackServer.

    The current parameter map used in this StackServer.

    Definition Classes
    Server → StackServer → Parameterized
  22. def productElementNames: Iterator[String]
    Definition Classes
    Product
  23. def serve(addr: SocketAddress, factory: ServiceFactory[Command, Response]): ListeningServer

    Serve service at addr

    Serve service at addr

    Definition Classes
    ListeningStackServer → Server
  24. final def serve(addr: String, service: Service[Command, Response]): ListeningServer

    Serve service at addr

    Serve service at addr

    Definition Classes
    Server
  25. final def serve(addr: String, service: ServiceFactory[Command, Response]): ListeningServer

    Serve service at addr

    Serve service at addr

    Definition Classes
    Server
  26. final def serve(addr: SocketAddress, service: Service[Command, Response]): ListeningServer

    Serve service at addr

    Serve service at addr

    Definition Classes
    Server
  27. def serveAndAnnounce(name: String, service: Service[Command, Response]): ListeningServer

    Serve service at addr and announce with name.

    Serve service at addr and announce with name. Announcements will be removed when the service is closed. Omitting the addr will bind to an ephemeral port.

    Definition Classes
    Server
  28. def serveAndAnnounce(name: String, service: ServiceFactory[Command, Response]): ListeningServer

    Serve service at addr and announce with name.

    Serve service at addr and announce with name. Announcements will be removed when the service is closed. Omitting the addr will bind to an ephemeral port.

    Definition Classes
    Server
  29. def serveAndAnnounce(name: String, addr: String, service: Service[Command, Response]): ListeningServer

    Serve service at addr and announce with name.

    Serve service at addr and announce with name. Announcements will be removed when the service is closed. Omitting the addr will bind to an ephemeral port.

    Definition Classes
    Server
  30. def serveAndAnnounce(name: String, addr: String, service: ServiceFactory[Command, Response]): ListeningServer

    Serve service at addr and announce with name.

    Serve service at addr and announce with name. Announcements will be removed when the service is closed. Omitting the addr will bind to an ephemeral port.

    Definition Classes
    Server
  31. def serveAndAnnounce(name: String, addr: SocketAddress, service: Service[Command, Response]): ListeningServer

    Serve service at addr and announce with name.

    Serve service at addr and announce with name. Announcements will be removed when the service is closed. Omitting the addr will bind to an ephemeral port.

    Definition Classes
    Server
  32. def serveAndAnnounce(name: String, addr: SocketAddress, service: ServiceFactory[Command, Response]): ListeningServer

    Serve service at addr and announce with name.

    Serve service at addr and announce with name. Announcements will be removed when the service is closed. Omitting the addr will bind to an ephemeral port.

    Definition Classes
    Server
  33. val stack: Stack[ServiceFactory[Command, Response]]

    The current stack used in this StackServer.

    The current stack used in this StackServer.

    Definition Classes
    Server → StackServer
  34. final def synchronized[T0](arg0: => T0): T0
    Definition Classes
    AnyRef
  35. def transformed(t: Transformer): Server

    Definition Classes
    ListeningStackServer → StackServer → Transformable
    See also

    withStack

  36. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])
  37. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])
  38. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException]) @native()
  39. val withAdmissionControl: ServerAdmissionControlParams[Server]

    An entry point for configuring the servers' admission control.

    An entry point for configuring the servers' admission control.

    Definition Classes
    Server → WithServerAdmissionControl
  40. def withExceptionStatsHandler(exceptionStatsHandler: ExceptionStatsHandler): Server

    Configures this server or client with given exception stats handler.

    Configures this server or client with given exception stats handler.

    Definition Classes
    Server → CommonParams
  41. def withExecutionOffloaded(pool: FuturePool): Server

    Configures this server or client to shift user-defined computation (com.twitter.util.Future callbacks and transformations) off of IO threads into a given FuturePool.

    Configures this server or client to shift user-defined computation (com.twitter.util.Future callbacks and transformations) off of IO threads into a given FuturePool.

    By default, Finagle executes all futures in the IO threads, minimizing context switches. Given there is usually a fixed number of IO threads shared across a JVM process, it's critically important to ensure they aren't being blocked by the application code, affecting system's responsiveness. Shifting application-level work onto a dedicated FuturePool or ExecutorService offloads IO threads, which may improve throughput in CPU-bound systems.

    As always, run your own tests before enabling this feature.

    Definition Classes
    Server → CommonParams
  42. def withExecutionOffloaded(executor: ExecutorService): Server

    Configures this server or client to shift user-defined computation (com.twitter.util.Future callbacks and transformations) off of IO threads into a given ExecutorService.

    Configures this server or client to shift user-defined computation (com.twitter.util.Future callbacks and transformations) off of IO threads into a given ExecutorService.

    By default, Finagle executes all futures in the IO threads, minimizing context switches. Given there is usually a fixed number of IO threads shared across a JVM process, it's critically important to ensure they aren't being blocked by the application code, affecting system's responsiveness. Shifting application-level work onto a dedicated FuturePool or ExecutorService offloads IO threads, which may improve throughput in CPU-bound systems.

    As always, run your own tests before enabling this feature.

    Definition Classes
    Server → CommonParams
  43. def withLabel(label: String): Server

    Configures this server or client with given label (default: empty string).

    Configures this server or client with given label (default: empty string).

    The label value is used for stats reporting to scope stats reported from different clients/servers to a single stats receiver.

    Definition Classes
    Server → CommonParams
  44. def withLabels(keywords: String*): Server
    Definition Classes
    CommonParams
  45. def withMonitor(monitor: Monitor): Server

    Configures this server or client with given util.Monitor (default: com.twitter.finagle.util.NullMonitor).

    Configures this server or client with given util.Monitor (default: com.twitter.finagle.util.NullMonitor).

    Monitors are Finagle's out-of-band exception reporters. Whenever an exception is thrown on a request path, it's reported to the monitor. The configured Monitor is composed (see below for how composition works) with the default monitor implementation, com.twitter.finagle.util.DefaultMonitor, which logs these exceptions.

    Monitors are wired into the server or client stacks via com.twitter.finagle.filter.MonitorFilter and are applied to the following kinds of exceptions:

    • Synchronous exceptions thrown on request path, Service.apply(request)
    • Asynchronous exceptions (failed futures) thrown on request path, Service.apply(request)
    • Exceptions thrown from respond, onSuccess, onFailure future callbacks
    • Fatal exceptions thrown from map, flatMap, transform future continuations

    Put it this way, we apply Monitor.handle to an exception if we would otherwise "lose" it, i.e. when it's not connected to the Future, nor is it connected to the call stack.

    You can compose multiple monitors if you want to extend or override the standard behavior, defined in DefaultMonitor.

    import com.twitter.util.Monitor

val consoleMonitor = new Monitor {
  def handle(exc: Throwable): Boolean = {
    Console.err.println(exc.toString)
    false // continue handling with the next monitor (usually DefaultMonitor)
   }
}

$.withMonitor(consoleMonitor)

    Returning true form within a monitor effectively terminates the monitor chain so no exceptions are propagated down to the next monitor.

    Definition Classes
    Server → CommonParams
  46. def withParams(params: Params): Server

    Creates a new StackServer with params used to configure this StackServer's stack.

    Creates a new StackServer with params used to configure this StackServer's stack.

    Definition Classes
    ListeningStackServer → StackServer → Parameterized
  47. def withRequestTimeout(timeout: Duration): Server

    Configures the request timeout of this server or client (default: unbounded).

    Configures the request timeout of this server or client (default: unbounded).

    If the request has not completed within the given timeout, the pending work will be interrupted via com.twitter.util.Future.raise.

    Client's Request Timeout

    The client request timeout is the maximum amount of time given to a single request (if there are retries, they each get a fresh request timeout). The timeout is applied only after a connection has been acquired. That is: it is applied to the interval between the dispatch of the request and the receipt of the response.

    Server's Request Timeout

    The server request timeout is the maximum amount of time, a server is allowed to spend handling the incoming request. Using the Finagle terminology, this is an amount of time after which a non-satisfied future returned from the user-defined service times out.

    Definition Classes
    Server → CommonParams
    See also

    https://twitter.github.io/finagle/guide/Clients.html#timeouts-expiration

  48. def withRequestTimeout(timeout: Tunable[Duration]): Server

    Configures the Tunable request timeout of this server or client (if applying the Tunable produces a value of None, an unbounded timeout is used for the request).

    Configures the Tunable request timeout of this server or client (if applying the Tunable produces a value of None, an unbounded timeout is used for the request).

    If the request has not completed within the Duration resulting from timeout.apply(), the pending work will be interrupted via com.twitter.util.Future.raise.

    Client's Request Timeout

    The client request timeout is the maximum amount of time given to a single request (if there are retries, they each get a fresh request timeout). The timeout is applied only after a connection has been acquired. That is: it is applied to the interval between the dispatch of the request and the receipt of the response.

    Server's Request Timeout

    The server request timeout is the maximum amount of time, a server is allowed to spend handling the incoming request. Using the Finagle terminology, this is an amount of time after which a non-satisfied future returned from the user-defined service times out.

    Definition Classes
    CommonParams
    See also

    https://twitter.github.io/finagle/guide/Clients.html#timeouts-expiration and https://twitter.github.io/finagle/guide/Configuration.html#tunables

  49. def withResponseClassifier(responseClassifier: ResponseClassifier): Server

    Configure a com.twitter.finagle.service.ResponseClassifier which is used to determine the result of a request/response.

    Configure a com.twitter.finagle.service.ResponseClassifier which is used to determine the result of a request/response.

    This allows developers to give Finagle the additional application-specific knowledge necessary in order to properly classify responses. Without this, Finagle cannot make judgements about application-level failures as it only has a narrow understanding of failures (for example: transport level, timeouts, and nacks).

    As an example take an HTTP server that returns a response with a 500 status code. To Finagle this is a successful request/response. However, the application developer may want to treat all 500 status codes as failures and can do so via setting a com.twitter.finagle.service.ResponseClassifier.

    ResponseClassifier is a PartialFunction and as such multiple classifiers can be composed together via PartialFunction.orElse.

    Response classification is independently configured on the client and server. For client-side response classification using com.twitter.finagle.builder.ClientBuilder, see com.twitter.finagle.builder.ClientBuilder.responseClassifier

    Definition Classes
    CommonParams
    Note

    If unspecified, the default classifier is com.twitter.finagle.service.ResponseClassifier.Default which is a total function fully covering the input domain.

    See also

    com.twitter.finagle.http.service.HttpResponseClassifier for some HTTP classification tools.

  50. val withSession: ServerSessionParams[Server]

    An entry point for configuring the client's sessions.

    An entry point for configuring the client's sessions.

    Session might be viewed as logical connection that wraps a physical connection (i.e., transport) and controls its lifecycle. Sessions are used in Finagle to maintain liveness, requests cancellation, draining, and many more.

    The default setup for a Finagle server's sessions is to not put any timeouts on it.

    Definition Classes
    Server → WithServerSession
  51. def withStack(fn: (Stack[ServiceFactory[Command, Response]]) => Stack[ServiceFactory[Command, Response]]): Server

    A new StackServer using the function to create a new Stack.

    A new StackServer using the function to create a new Stack.

    The input to fn is the client's current stack. This API allows for easier usage when writing code that uses method chaining.

    This method is similar to transformed while providing easier API ergonomics for one-off Stack changes.

    Definition Classes
    Server → ListeningStackServer → StackServer
    Example:

    1. From Scala:

      import com.twitter.finagle.Http

Http.server.withStack(_.prepend(MyStackModule))

      From Java:

      import com.twitter.finagle.Http;
import static com.twitter.util.Function.func;

Http.server().withStack(func(stack -> stack.prepend(MyStackModule)));
    See also

    withStack(Stack)

    transformed

  52. def withStack(stack: Stack[ServiceFactory[Command, Response]]): Server

    A new StackServer with the provided Stack.

    A new StackServer with the provided Stack.

    Definition Classes
    Server → ListeningStackServer → StackServer
    See also

    withStack that takes a Function1 for a more ergonomic API when used with method chaining.

  53. def withStatsReceiver(statsReceiver: StatsReceiver): Server

    Configures this server or client with given stats.StatsReceiver (default: stats.DefaultStatsReceiver).

    Configures this server or client with given stats.StatsReceiver (default: stats.DefaultStatsReceiver).

    Definition Classes
    Server → CommonParams
  54. def withTracer(tracer: Tracer): Server

    Configures this server or client with given tracing.Tracer (default: com.twitter.finagle.tracing.DefaultTracer).

    Configures this server or client with given tracing.Tracer (default: com.twitter.finagle.tracing.DefaultTracer).

    Definition Classes
    Server → CommonParams
    Note

    if you supply com.twitter.finagle.tracing.NullTracer, no trace information will be written, but this does not disable Finagle from propagating trace information. Instead, if traces are being aggregated across your fleet, it will orphan subsequent spans.

  55. val withTransport: ServerTransportParams[Server]

    An entry point for configuring servers' com.twitter.finagle.transport.Transport.

    An entry point for configuring servers' com.twitter.finagle.transport.Transport.

    Transport is a Finagle abstraction over the network connection (i.e., a TCP connection).

    Definition Classes
    Server → WithServerTransport

Inherited from Serializable

Inherited from Product

Inherited from Equals

Inherited from StdStackServer[Command, Response, Server]

Inherited from ListeningStackServer[Command, Response, Server]

Inherited from WithServerAdmissionControl[Server]

Inherited from WithServerSession[Server]

Inherited from WithServerTransport[Server]

Inherited from CommonParams[Server]

Inherited from StackServer[Command, Response]

Inherited from StackBasedServer[Command, Response]

Inherited from Transformable[Server]

Inherited from Parameterized[Server]

Inherited from finagle.Server[Command, Response]

Inherited from AnyRef

Inherited from Any

Ungrouped