org.apache.samza.table.remote.TableWriteFunction.java Source code

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Here is the source code for org.apache.samza.table.remote.TableWriteFunction.java

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/*
 * 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.samza.table.remote;

import java.io.Serializable;
import java.util.Collection;
import java.util.List;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ExecutionException;
import java.util.stream.Collectors;

import org.apache.samza.SamzaException;
import org.apache.samza.annotation.InterfaceStability;
import org.apache.samza.operators.functions.ClosableFunction;
import org.apache.samza.operators.functions.InitableFunction;
import org.apache.samza.storage.kv.Entry;

import com.google.common.collect.Iterables;

/**
 * A function object to be used with a remote read/write table implementation. It encapsulates the functionality
 * of writing table record(s) for a provided set of key(s) to the store.
 *
 * <p> Instances of {@link TableWriteFunction} are meant to be serializable. ie. any non-serializable state
 * (eg: network sockets) should be marked as transient and recreated inside readObject().
 *
 * <p> Implementations are expected to be thread-safe.
 * @param <K> the type of the key in this table
 * @param <V> the type of the value in this table
 */
@InterfaceStability.Unstable
public interface TableWriteFunction<K, V> extends TablePart, InitableFunction, ClosableFunction, Serializable {
    /**
     * Store single table {@code record} with specified {@code key}. This method must be thread-safe.
     * The default implementation calls putAsync and blocks on the completion afterwards.
     *
     * @param key key for the table record
     * @param record table record to be written
     */
    default void put(K key, V record) {
        try {
            putAsync(key, record).get();
        } catch (InterruptedException | ExecutionException e) {
            throw new SamzaException("PUT failed for " + key, e);
        }
    }

    /**
     * Asynchronously store single table {@code record} with specified {@code key}. This method must be thread-safe.
     * @param key key for the table record
     * @param record table record to be written
     * @return CompletableFuture for the put request
     */
    CompletableFuture<Void> putAsync(K key, V record);

    /**
     * Store the table {@code records} with specified {@code keys}. This method must be thread-safe.
     * The default implementation calls putAllAsync and blocks on the completion afterwards.
     * @param records table records to be written
     */
    default void putAll(List<Entry<K, V>> records) {
        try {
            putAllAsync(records).get();
        } catch (InterruptedException | ExecutionException e) {
            throw new SamzaException("PUT_ALL failed for " + records, e);
        }
    }

    /**
     * Asynchronously store the table {@code records} with specified {@code keys}. This method must be thread-safe.
     * The default implementation calls putAsync for each entry and return a combined future.
     * @param records table records to be written
     * @return CompletableFuture for the put request
     */
    default CompletableFuture<Void> putAllAsync(Collection<Entry<K, V>> records) {
        List<CompletableFuture<Void>> putFutures = records.stream().map(e -> putAsync(e.getKey(), e.getValue()))
                .collect(Collectors.toList());
        return CompletableFuture.allOf(Iterables.toArray(putFutures, CompletableFuture.class));
    }

    /**
     * Delete the {@code record} with specified {@code key} from the remote store.
     * The default implementation calls deleteAsync and blocks on the completion afterwards.
     * @param key key to the table record to be deleted
     */
    default void delete(K key) {
        try {
            deleteAsync(key).get();
        } catch (InterruptedException | ExecutionException e) {
            throw new SamzaException("DELETE failed for " + key, e);
        }
    }

    /**
     * Asynchronously delete the {@code record} with specified {@code key} from the remote store
     * @param key key to the table record to be deleted
     * @return CompletableFuture for the delete request
     */
    CompletableFuture<Void> deleteAsync(K key);

    /**
     * Delete all {@code records} with the specified {@code keys} from the remote store
     * The default implementation calls deleteAllAsync and blocks on the completion afterwards.
     * @param keys keys for the table records to be written
     */
    default void deleteAll(Collection<K> keys) {
        try {
            deleteAllAsync(keys).get();
        } catch (InterruptedException | ExecutionException e) {
            throw new SamzaException("DELETE failed for " + keys, e);
        }
    }

    /**
     * Asynchronously delete all {@code records} with the specified {@code keys} from the remote store.
     * The default implementation calls deleteAsync for each key and return a combined future.
     *
     * @param keys keys for the table records to be written
     * @return CompletableFuture for the deleteAll request
     */
    default CompletableFuture<Void> deleteAllAsync(Collection<K> keys) {
        List<CompletableFuture<Void>> deleteFutures = keys.stream().map(this::deleteAsync)
                .collect(Collectors.toList());
        return CompletableFuture.allOf(Iterables.toArray(deleteFutures, CompletableFuture.class));
    }

    /**
     * Determine whether the current operation can be retried with the last thrown exception.
     * @param exception exception thrown by a table operation
     * @return whether the operation can be retried
     */
    boolean isRetriable(Throwable exception);

    /**
     * Flush the remote store (optional)
     */
    default void flush() {
    }

    // optionally implement readObject() to initialize transient states
}