Package io.servicetalk.http.api

Interface HttpLifecycleObserver.HttpExchangeObserver

All Known Subinterfaces:

GrpcLifecycleObserver.GrpcExchangeObserver

Enclosing interface:

HttpLifecycleObserver

public static interface HttpLifecycleObserver.HttpExchangeObserver

An observer interface that provides visibility into events associated with a single HTTP exchange.

An exchange is represented by a request and a response. Both can be observed independently via their corresponding observers and may publish their events concurrently with each other because connections are full-duplex. The final event for the exchange is signaled only after both nested observers terminate. It guarantees visibility of both observers internal states inside the final callback.

Method Summary

Modifier and Type	Method	Description
default void	onConnectionSelected(ConnectionInfo info)	Callback when a connection is selected for this exchange execution.
default void	onExchangeFinally()	Callback when the exchange completes.
default HttpLifecycleObserver.HttpRequestObserver	onRequest(HttpRequestMetaData requestMetaData)	Callback when a request starts.
default HttpLifecycleObserver.HttpResponseObserver	onResponse(HttpResponseMetaData responseMetaData)	Callback when a response meta-data was observed.
default void	onResponseCancel()	Callback if the response meta-data was cancelled.
default void	onResponseError(Throwable cause)	Callback if the response meta-data was not received due to an error.

Method Details

onConnectionSelected

default void onConnectionSelected(ConnectionInfo info)

Callback when a connection is selected for this exchange execution.

Parameters:

info - ConnectionInfo of the selected connection

onRequest

default HttpLifecycleObserver.HttpRequestObserver onRequest(HttpRequestMetaData requestMetaData)

Callback when a request starts.

Parameters:

requestMetaData - The corresponding HttpRequestMetaData

Returns:

an HttpLifecycleObserver.HttpRequestObserver that provides visibility into request events

onResponse

default HttpLifecycleObserver.HttpResponseObserver onResponse(HttpResponseMetaData responseMetaData)

Callback when a response meta-data was observed.

Either this or onResponseError(Throwable) callback can be invoked, but not both.

Parameters:

responseMetaData - the corresponding HttpResponseMetaData

Returns:

an HttpLifecycleObserver.HttpResponseObserver that provides visibility into response events

onResponseError

default void onResponseError(Throwable cause)

Callback if the response meta-data was not received due to an error.

Either this or onResponse(HttpResponseMetaData) callback can be invoked, but not both.

Parameters:

cause - the cause of a response meta-data failure

onResponseCancel

default void onResponseCancel()

Callback if the response meta-data was cancelled.

Cancellation is the best effort, more events may be signaled after cancel.

onExchangeFinally

default void onExchangeFinally()

Callback when the exchange completes.

This is the final callback that is invoked after HttpLifecycleObserver.HttpRequestObserver terminates and either HttpLifecycleObserver.HttpResponseObserver terminates or onResponseError(Throwable)/onResponseCancel() method is invoked. Inside this callback, users can safely consume the internal state of all other callbacks without the need for additional synchronization.