org.axonframework.extensions.springcloud.commandhandling.mode

Class IgnoreListingDiscoveryMode

java.lang.Object

org.axonframework.extensions.springcloud.commandhandling.mode.AbstractCapabilityDiscoveryMode<IgnoreListingDiscoveryMode>

org.axonframework.extensions.springcloud.commandhandling.mode.IgnoreListingDiscoveryMode

All Implemented Interfaces:

CapabilityDiscoveryMode

public class IgnoreListingDiscoveryMode
extends AbstractCapabilityDiscoveryMode<IgnoreListingDiscoveryMode>

Wrapper implementation of the CapabilityDiscoveryMode, delegating all operations to another CapabilityDiscoveryMode instance. When discovering capabilities(ServiceInstance), the given ServiceInstance might be added to the ignored instance list.

ServiceInstances are ignored whenever a ServiceInstanceClientException is thrown, upon which the ServiceInstance is stored for subsequent invocation. On the next capabilities(ServiceInstance) iteration, the given ServiceInstance is validated to not be present in the set of ignored service instance identifiers.

Ignored ServiceInstances are evicted from the list after a configurable expireThreshold (through the IgnoreListingDiscoveryMode.Builder.expireThreshold(Duration)). Eviction occurs during any> capabilities(ServiceInstance) invocation. It will thus run in line with the heartbeat configuration of the chosen Spring Cloud Discovery implementation.

Since:

4.4

Author:

Steven van Beelen

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	IgnoreListingDiscoveryMode.Builder Builder class to instantiate a IgnoreListingDiscoveryMode.

Field Summary

Fields

Modifier and Type	Field and Description
static Clock	clock Clock instance used to set the expiry time of ignored ServiceInstances.

Fields inherited from class org.axonframework.extensions.springcloud.commandhandling.mode.AbstractCapabilityDiscoveryMode

localCapabilities, localInstance

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	IgnoreListingDiscoveryMode(IgnoreListingDiscoveryMode.Builder builder) Instantiate a IgnoreListingDiscoveryMode based on the fields contained in the IgnoreListingDiscoveryMode.Builder.

Method Summary

Modifier and Type	Method and Description
static IgnoreListingDiscoveryMode.Builder	builder() Instantiate a IgnoreListingDiscoveryMode.Builder to be able to create a IgnoreListingDiscoveryMode.
Optional<MemberCapabilities>	capabilities(org.springframework.cloud.client.ServiceInstance serviceInstance) Discovers the capabilities of the given serviceInstance, returning an Optional MemberCapabilities.
void	updateLocalCapabilities(org.springframework.cloud.client.ServiceInstance localInstance, int loadFactor, org.axonframework.commandhandling.distributed.CommandMessageFilter commandFilter) Update the capabilities of the localInstance, defined through the given loadFactor and commandFilter.

Methods inherited from class java.lang.Object

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

Field Detail

clock

public static Clock clock

Clock instance used to set the expiry time of ignored ServiceInstances. May be adjusted to use a different timezone, or for testing purposes.

Constructor Detail

IgnoreListingDiscoveryMode

protected IgnoreListingDiscoveryMode(IgnoreListingDiscoveryMode.Builder builder)

Instantiate a IgnoreListingDiscoveryMode based on the fields contained in the IgnoreListingDiscoveryMode.Builder.

Will assert that the delegate CapabilityDiscoveryMode is not null and will throw an AxonConfigurationException if this is the case.

Parameters:

builder - the IgnoreListingDiscoveryMode.Builder used to instantiate a IgnoreListingDiscoveryMode instance

Method Detail

builder

public static IgnoreListingDiscoveryMode.Builder builder()

Instantiate a IgnoreListingDiscoveryMode.Builder to be able to create a IgnoreListingDiscoveryMode.

The expireThreshold is defaulted to a Duration of 1 minute. The delegate CapabilityDiscoveryMode is a hard requirement and as such should be provided.

Returns:

a IgnoreListingDiscoveryMode.Builder to be able to create a IgnoreListingDiscoveryMode

updateLocalCapabilities

public void updateLocalCapabilities(org.springframework.cloud.client.ServiceInstance localInstance,
                                    int loadFactor,
                                    org.axonframework.commandhandling.distributed.CommandMessageFilter commandFilter)

Description copied from interface: CapabilityDiscoveryMode

Update the capabilities of the localInstance, defined through the given loadFactor and commandFilter.

Specified by:

updateLocalCapabilities in interface CapabilityDiscoveryMode

Overrides:

updateLocalCapabilities in class AbstractCapabilityDiscoveryMode<IgnoreListingDiscoveryMode>

Parameters:

localInstance - the local ServiceInstance

loadFactor - the load factor of the local instance, defining the amount of load this instance can carry

commandFilter - a filter defining the CommandMessages the local instance is capable of handling

capabilities

public Optional<MemberCapabilities> capabilities(org.springframework.cloud.client.ServiceInstance serviceInstance)
                                          throws ServiceInstanceClientException

Description copied from interface: CapabilityDiscoveryMode

Discovers the capabilities of the given serviceInstance, returning an Optional MemberCapabilities.

Parameters:

serviceInstance - the ServiceInstance to discover MemberCapabilities for

Returns:

an Optional MemberCapabilities, based on the given serviceInstance

Throws:

ServiceInstanceClientException - whenever the ServiceInstance returns a client specific exception