Package com.linecorp.armeria.client.endpoint.healthcheck

Class HealthCheckedEndpointGroup

java.lang.Object

com.linecorp.armeria.common.util.AbstractListenable<List<Endpoint>>

com.linecorp.armeria.client.endpoint.DynamicEndpointGroup

com.linecorp.armeria.client.endpoint.healthcheck.HealthCheckedEndpointGroup

All Implemented Interfaces:

EndpointGroup, EndpointSelector, AsyncCloseable, Listenable<List<Endpoint>>, ListenableAsyncCloseable, AutoCloseable

public final class HealthCheckedEndpointGroup
extends DynamicEndpointGroup

An EndpointGroup that filters out unhealthy Endpoints from an existing EndpointGroup, by sending periodic health check requests.

 EndpointGroup originalGroup = ...

 // Decorate the EndpointGroup with HealthCheckedEndpointGroup
 // that sends HTTP health check requests to '/internal/l7check' every 10 seconds.
 HealthCheckedEndpointGroup healthCheckedGroup =
         HealthCheckedEndpointGroup.builder(originalGroup, "/internal/l7check")
                                   .protocol(SessionProtocol.HTTP)
                                   .retryInterval(Duration.ofSeconds(10))
                                   .build();

 // You must specify healthCheckedGroup when building a WebClient, otherwise health checking
 // will not be enabled.
 WebClient client = WebClient.builder(SessionProtocol.HTTP, healthCheckedGroup)
                             .build();
 

Method Summary

Modifier and Type	Method	Description
static HealthCheckedEndpointGroupBuilder	builder(EndpointGroup delegate, String path)	Returns a newly created HealthCheckedEndpointGroupBuilder that builds a HealthCheckedEndpointGroup which sends HTTP HEAD health check requests.
protected void	doCloseAsync(CompletableFuture<?> future)	Override this method to release the resources held by this EndpointGroup and complete the specified CompletableFuture.
MeterBinder	newMeterBinder(MeterIdPrefix idPrefix)	Returns a newly-created MeterBinder which binds the stats about this HealthCheckedEndpointGroup.
MeterBinder	newMeterBinder(String groupName)	Returns a newly-created MeterBinder which binds the stats about this HealthCheckedEndpointGroup with the default meter names.
static HealthCheckedEndpointGroup	of(EndpointGroup delegate, String path)	Returns a newly created HealthCheckedEndpointGroup that sends HTTP HEAD health check requests with default options.
long	selectionTimeoutMillis()	Returns the timeout to wait until a successful Endpoint selection.
String	toString()

Methods inherited from class com.linecorp.armeria.client.endpoint.DynamicEndpointGroup

addEndpoint, allowsEmptyEndpoints, builder, close, closeAsync, endpoints, isClosed, isClosing, latestValue, removeEndpoint, select, select, selectionStrategy, selectNow, setEndpoints, toString, toStringSelector, whenClosed, whenReady

Methods inherited from class com.linecorp.armeria.common.util.AbstractListenable

addListener, addListener, notifyListeners, removeListener

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.linecorp.armeria.client.endpoint.EndpointGroup

addListener, addListener, orElse, removeListener

Method Details

of

public static HealthCheckedEndpointGroup of(EndpointGroup delegate,
 String path)

Returns a newly created HealthCheckedEndpointGroup that sends HTTP HEAD health check requests with default options.

Parameters:

delegate - the EndpointGroup that provides the candidate Endpoints

path - the HTTP request path, e.g. "/internal/l7check"

builder

public static HealthCheckedEndpointGroupBuilder builder(EndpointGroup delegate,
 String path)

Returns a newly created HealthCheckedEndpointGroupBuilder that builds a HealthCheckedEndpointGroup which sends HTTP HEAD health check requests.

Parameters:

delegate - the EndpointGroup that provides the candidate Endpoints

path - the HTTP request path, e.g. "/internal/l7check"

selectionTimeoutMillis

public long selectionTimeoutMillis()

Description copied from interface: EndpointGroup

Returns the timeout to wait until a successful Endpoint selection. If an Endpoint is not resolved by this EndpointGroup within the timeout, a null value will be returned by EndpointSelector.select(ClientRequestContext, ScheduledExecutorService). The null Endpoint may cause a client request end with an EndpointSelectionTimeoutException if no RetryingClient is configured.

0 means EndpointGroup.selectNow(ClientRequestContext) should always return an Endpoint.

Specified by:

selectionTimeoutMillis in interface EndpointGroup

Overrides:

selectionTimeoutMillis in class DynamicEndpointGroup

doCloseAsync

protected void doCloseAsync(CompletableFuture<?> future)

Description copied from class: DynamicEndpointGroup

Override this method to release the resources held by this EndpointGroup and complete the specified CompletableFuture.

Overrides:

doCloseAsync in class DynamicEndpointGroup

newMeterBinder

public MeterBinder newMeterBinder(String groupName)

Returns a newly-created MeterBinder which binds the stats about this HealthCheckedEndpointGroup with the default meter names.

newMeterBinder

public MeterBinder newMeterBinder(MeterIdPrefix idPrefix)

Returns a newly-created MeterBinder which binds the stats about this HealthCheckedEndpointGroup.

toString

public String toString()

Overrides:

toString in class DynamicEndpointGroup