Package io.grpc.util

Class OutlierDetectionLoadBalancer

java.lang.Object

io.grpc.LoadBalancer

io.grpc.util.OutlierDetectionLoadBalancer

@Internal
public final class OutlierDetectionLoadBalancer
extends LoadBalancer

Wraps a child LoadBalancer while monitoring for outlier backends and removing them from the use of the child LB.

This implements the outlier detection gRFC: https://github.com/grpc/proposal/blob/master/A50-xds-outlier-detection.md

The implementation maintains two maps. Each endpoint status is tracked using an EndpointTracker. E.g. for two endpoints with these address list and their tracker: Endpoint e1 : [a1, a2] is tracked with EndpointTracker t1 Endpoint e2 : [a3] is tracked with EndpointTracker t2 The two maps are: First, addressMap maps from socket address -> endpoint tracker : [a1 -> t1, a2 -> t1, a3 -> t2] EndpointTracker has reference to all the subchannels of the corresponding endpoint. Second, trackerMap maps from unordered address set -> endpoint tracker. Updated upon address updates.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	OutlierDetectionLoadBalancer.OutlierDetectionLoadBalancerConfig	The configuration for OutlierDetectionLoadBalancer.

Nested classes/interfaces inherited from class io.grpc.LoadBalancer

LoadBalancer.CreateSubchannelArgs, LoadBalancer.ErrorPicker, LoadBalancer.Factory, LoadBalancer.FixedResultPicker, LoadBalancer.Helper, LoadBalancer.PickDetailsConsumer, LoadBalancer.PickResult, LoadBalancer.PickSubchannelArgs, LoadBalancer.ResolvedAddresses, LoadBalancer.Subchannel, LoadBalancer.SubchannelPicker, LoadBalancer.SubchannelStateListener

Field Summary

Fields inherited from class io.grpc.LoadBalancer

ATTR_HEALTH_CHECKING_CONFIG, DISABLE_SUBCHANNEL_RECONNECT_KEY, EMPTY_PICKER, HAS_HEALTH_PRODUCER_LISTENER_KEY, HEALTH_CONSUMER_LISTENER_ARG_KEY, IS_PETIOLE_POLICY

Constructor Summary

Constructors

Constructor	Description
OutlierDetectionLoadBalancer(LoadBalancer.Helper helper, TimeProvider timeProvider)	Creates a new instance of OutlierDetectionLoadBalancer.

Method Summary

Modifier and Type	Method	Description
Status	acceptResolvedAddresses(LoadBalancer.ResolvedAddresses resolvedAddresses)	Accepts newly resolved addresses from the name resolution system.
void	handleNameResolutionError(Status error)	Handles an error from the name resolution system.
void	shutdown()	The channel asks the load-balancer to shutdown.

Methods inherited from class io.grpc.LoadBalancer

canHandleEmptyAddressListFromNameResolution, handleResolvedAddresses, handleSubchannelState, requestConnection

Methods inherited from class java.lang.Object

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

Constructor Details

OutlierDetectionLoadBalancer

public OutlierDetectionLoadBalancer(LoadBalancer.Helper helper,
 TimeProvider timeProvider)

Creates a new instance of OutlierDetectionLoadBalancer.

Method Details

acceptResolvedAddresses

public Status acceptResolvedAddresses(LoadBalancer.ResolvedAddresses resolvedAddresses)

Description copied from class: LoadBalancer

Accepts newly resolved addresses from the name resolution system. The EquivalentAddressGroup addresses should be considered equivalent but may be flattened into a single list if needed.

Implementations can choose to reject the given addresses by returning false.

Implementations should not modify the given addresses.

Overrides:

acceptResolvedAddresses in class LoadBalancer

Parameters:

resolvedAddresses - the resolved server addresses, attributes, and config.

Returns:

true if the resolved addresses were accepted. false if rejected.

handleNameResolutionError

public void handleNameResolutionError(Status error)

Description copied from class: LoadBalancer

Handles an error from the name resolution system.

Specified by:

handleNameResolutionError in class LoadBalancer

Parameters:

error - a non-OK status

shutdown

public void shutdown()

Description copied from class: LoadBalancer

The channel asks the load-balancer to shutdown. No more methods on this class will be called after this method. The implementation should shutdown all Subchannels and OOB channels, and do any other cleanup as necessary.

Specified by:

shutdown in class LoadBalancer