Package io.servicetalk.http.netty

Class HttpLifecycleObserverRequesterFilter

java.lang.Object

io.servicetalk.http.netty.HttpLifecycleObserverRequesterFilter

All Implemented Interfaces:

HttpExecutionStrategyInfluencer, StreamingHttpClientFilterFactory, StreamingHttpConnectionFilterFactory, ExecutionStrategyInfluencer<HttpExecutionStrategy>

Direct Known Subclasses:

GrpcLifecycleObserverRequesterFilter

public class HttpLifecycleObserverRequesterFilter
extends Object
implements StreamingHttpClientFilterFactory, StreamingHttpConnectionFilterFactory

An HTTP requester filter that tracks events during request/response lifecycle.

The result of the observed behavior will depend on the position of this filter in the execution chain. This filter is recommended to be appended as the first client filter on the builder to account for all work done by other filters. It can be appended at another position, considering the following:

• After a tracing filter or any other filter that populates request context, AsyncContext, MDC, or alters HttpRequestMetaData if that information has to be available for HttpLifecycleObserver.HttpExchangeObserver.
• After RedirectingHttpRequesterFilter if each redirect should be observed as an independent exchange.
• After RetryingHttpRequesterFilter if each retry attempt should be observed as an independent exchange.
• As a connection filter if no user-defined RetryingHttpRequesterFilter is appended manually but the default auto-retries should be observed as an independent exchange.
• As the last connection filter if only network interactions should be observed without accounting for work of any other filters.
• After TimeoutHttpRequesterFilter if the timeout event should be observed as cancellation instead of an error.
• Before any filter that populates response context or alters HttpResponseMetaData if that information has to be available for HttpLifecycleObserver.HttpExchangeObserver.
• Before any filter that maps/translates HttpResponseMetaData into an exception or throws an exception during response payload body transformation if that exception has to be observed by HttpLifecycleObserver.HttpExchangeObserver.
• Using SingleAddressHttpClientBuilder.appendClientFilter(Predicate, StreamingHttpClientFilterFactory) or SingleAddressHttpClientBuilder.appendConnectionFilter(Predicate, StreamingHttpConnectionFilterFactory) if the observer should be applied conditionally.

Constructor Summary

Constructors

Constructor	Description
HttpLifecycleObserverRequesterFilter(HttpLifecycleObserver observer)	Create a new instance.

Method Summary

Modifier and Type	Method	Description
final StreamingHttpClientFilter	create(FilterableStreamingHttpClient client)	Creates a StreamingHttpClientFilter using the provided StreamingHttpClientFilter.
final StreamingHttpConnectionFilter	create(FilterableStreamingHttpConnection connection)	Create a StreamingHttpConnectionFilter using the provided FilterableStreamingHttpConnection.
List<? extends HttpLifecycleObserver>	lifecycleObservers()	Returns the HttpLifecycleObservers used by this filter.
final HttpExecutionStrategy	requiredOffloads()	Return an ExecutionStrategy that describes the offloads required by the influencer.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface io.servicetalk.http.api.HttpExecutionStrategyInfluencer

influenceStrategy, requiredOffloads

Constructor Details

HttpLifecycleObserverRequesterFilter

public HttpLifecycleObserverRequesterFilter(HttpLifecycleObserver observer)

Create a new instance.

Parameters:

observer - The observer implementation that consumes HTTP lifecycle events.

Method Details

create

public final StreamingHttpClientFilter create(FilterableStreamingHttpClient client)

Description copied from interface: StreamingHttpClientFilterFactory

Creates a StreamingHttpClientFilter using the provided StreamingHttpClientFilter.

Specified by:

create in interface StreamingHttpClientFilterFactory

Parameters:

client - FilterableStreamingHttpClient to filter

Returns:

StreamingHttpClientFilter using the provided StreamingHttpClientFilter.

create

public final StreamingHttpConnectionFilter create(FilterableStreamingHttpConnection connection)

Description copied from interface: StreamingHttpConnectionFilterFactory

Create a StreamingHttpConnectionFilter using the provided FilterableStreamingHttpConnection.

Specified by:

create in interface StreamingHttpConnectionFilterFactory

Parameters:

connection - FilterableStreamingHttpConnection to filter

Returns:

StreamingHttpConnectionFilter using the provided FilterableStreamingHttpConnection.

lifecycleObservers

public List<? extends HttpLifecycleObserver> lifecycleObservers()

Returns the HttpLifecycleObservers used by this filter.

Returns:

a List of HttpLifecycleObservers used by this filter

requiredOffloads

public final HttpExecutionStrategy requiredOffloads()

Description copied from interface: HttpExecutionStrategyInfluencer

Return an ExecutionStrategy that describes the offloads required by the influencer.

The provided default implementation requests offloading of all operations. Implementations that require no offloading should be careful to return HttpExecutionStrategies.offloadNone() rather than HttpExecutionStrategies.offloadNever(). Implementations should avoid returning HttpExecutionStrategies.defaultStrategy(), instead returning the strategy they require or HttpExecutionStrategies.offloadAll() if offloading for all paths is required (safe default).

Specified by:

requiredOffloads in interface ExecutionStrategyInfluencer<HttpExecutionStrategy>

Specified by:

requiredOffloads in interface HttpExecutionStrategyInfluencer

Returns:

the ExecutionStrategy required by the influencer.