statefun-flink/statefun-flink-core/src/main/java/org/apache/flink/statefun/flink/core/backpressure/InternalContext.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.flink.statefun.flink.core.backpressure;

import org.apache.flink.annotation.Internal;
import org.apache.flink.statefun.flink.core.metrics.FunctionTypeMetrics;
import org.apache.flink.statefun.sdk.Context;

@Internal
public interface InternalContext extends Context {

  /**
   * Signals the runtime to stop invoking the currently executing function with new input until at
   * least one {@link org.apache.flink.statefun.sdk.AsyncOperationResult} belonging to this function
   * would be delivered.
   *
   * <p>NOTE: If a function would request to block without actually registering any async operations
   * either previously or during its current invocation, then it would remain blocked. Since this is
   * an internal API to be used by the remote functions we don't do anything to prevent that.
   *
   * <p>If we would like it to be a part of the SDK then we would have to make sure that we track
   * every async operation registered per each address.
   */
  void awaitAsyncOperationComplete();

  /**
   * Returns the metrics handle for the current invoked function's type.
   *
   * @return the metrics handle for the current invoked function's type.
   */
  FunctionTypeMetrics functionTypeMetrics();
}