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/*
 * Copyright © 2017 camunda services GmbH ([email protected])
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package io.zeebe.logstreams.processor;

import io.zeebe.util.sched.AsyncContext;
import io.zeebe.util.sched.future.ActorFuture;

public class EventLifecycleContext implements AsyncContext
{
    private ActorFuture future;

    /**
     * Use with care
     * 
     * If you need to perform an async action (like fetching some data) while processing the event, you
     * can supply a future here. Note that:
     * 

     * the async action should not be a side effect (in that case use {@link StreamProcessorController#executeSideEffects()}).
     * if the outcome of the action influences the outcome of processing the event (ie. based on the return
     * value of the async action either a command succeeds or is rejected, make sure that reprocessing produces the
     * same results. There are two cases:
     * 
     * In case the async action always returns the same data no extra care is necessary
     * In case the async action does not always return the same data, make sure to a) send responses to a client
     * based on the event that is written to the stream, b) do not update state on the command but rather on the event.
     * 
     * 
     */

    @Override
    public void async(ActorFuture future)
    {
        this.future = future;
    }

    void reset()
    {
        future = null;
    }

    boolean hasFuture()
    {
        return future != null;
    }

    ActorFuture getFuture()
    {
        return future;
    }
}