/*
* Copyright (c) MuleSoft, Inc. All rights reserved. http://www.mulesoft.com
* The software in this package is published under the terms of the CPAL v1.0
* license, a copy of which has been included with this distribution in the
* LICENSE.txt file.
*/
package org.mule.runtime.core.policy;
import org.mule.runtime.core.api.Event;
import org.mule.runtime.core.api.processor.Processor;
import java.util.Optional;
/**
* State handler for policies execution.
*
* Keeps track of the operation associated with a certain context of execution. Such context of execution is defined by the unique
* identifier of the generated {@link Event}.
*
* Implementations will be executed concurrently but always using different identifiers. There will be no concurrent invocation
* for the same identifier.
*
* @since 4.0
*/
public interface PolicyStateHandler {
/**
* Associated the {@code identifier} with the policy next operation to execute
*
* @param executionIdentifier the identifier of the context
* @param nextOperation the next operation of the policy
*/
void updateNextOperation(String executionIdentifier, Processor nextOperation);
/**
* @param executionIdentifier the identifier of the context
* @return the next operation for the context.
*/
Processor retrieveNextOperation(String executionIdentifier);
/**
* Frees resources associated with the given context identifier
*
* @param executionIdentifier the identifier of the context
*/
void destroyState(String executionIdentifier);
/**
* @param identifier the identifier of the context
* @return the latest state of the policy for the given identifier. It may be empty if no other policy was executed before for
* this context.
*/
Optional<Event> getLatestState(PolicyStateId identifier);
/**
* Updates the event of the policy for the context with the given identifier.
*
* @param identifier the identifier of the context
* @param lastStateEvent the last state of the event
*/
void updateState(PolicyStateId identifier, Event lastStateEvent);
}