streams/src/test/java/org/apache/kafka/streams/processor/internals/assignment/SubscriptionInfoTest.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.kafka.streams.processor.internals.assignment;

import org.apache.kafka.streams.processor.TaskId;
import org.junit.Test;

import java.nio.ByteBuffer;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
import java.util.UUID;

import static org.junit.Assert.assertEquals;

public class SubscriptionInfoTest {
    private final UUID processId = UUID.randomUUID();
    private final Set<TaskId> activeTasks = new HashSet<>(Arrays.asList(
        new TaskId(0, 0),
        new TaskId(0, 1),
        new TaskId(1, 0)));
    private final Set<TaskId> standbyTasks = new HashSet<>(Arrays.asList(
        new TaskId(1, 1),
        new TaskId(2, 0)));

    private final static String IGNORED_USER_ENDPOINT = "ignoredUserEndpoint:80";

    @Test
    public void shouldUseLatestSupportedVersionByDefault() {
        final SubscriptionInfo info = new SubscriptionInfo(processId, activeTasks, standbyTasks, "localhost:80");
        assertEquals(SubscriptionInfo.LATEST_SUPPORTED_VERSION, info.version());
    }

    @Test(expected = IllegalArgumentException.class)
    public void shouldThrowForUnknownVersion1() {
        new SubscriptionInfo(0, processId, activeTasks, standbyTasks, "localhost:80");
    }

    @Test(expected = IllegalArgumentException.class)
    public void shouldThrowForUnknownVersion2() {
        new SubscriptionInfo(SubscriptionInfo.LATEST_SUPPORTED_VERSION + 1, processId, activeTasks, standbyTasks, "localhost:80");
    }

    @Test
    public void shouldEncodeAndDecodeVersion1() {
        final SubscriptionInfo info = new SubscriptionInfo(1, processId, activeTasks, standbyTasks, IGNORED_USER_ENDPOINT);
        final SubscriptionInfo expectedInfo = new SubscriptionInfo(1, SubscriptionInfo.UNKNOWN, processId, activeTasks, standbyTasks, null);
        assertEquals(expectedInfo, SubscriptionInfo.decode(info.encode()));
    }

    @Test
    public void shouldEncodeAndDecodeVersion2() {
        final SubscriptionInfo info = new SubscriptionInfo(2, processId, activeTasks, standbyTasks, "localhost:80");
        final SubscriptionInfo expectedInfo = new SubscriptionInfo(2, SubscriptionInfo.UNKNOWN, processId, activeTasks, standbyTasks, "localhost:80");
        assertEquals(expectedInfo, SubscriptionInfo.decode(info.encode()));
    }

    @Test
    public void shouldEncodeAndDecodeVersion3() {
        final SubscriptionInfo info = new SubscriptionInfo(3, processId, activeTasks, standbyTasks, "localhost:80");
        final SubscriptionInfo expectedInfo = new SubscriptionInfo(3, SubscriptionInfo.LATEST_SUPPORTED_VERSION, processId, activeTasks, standbyTasks, "localhost:80");
        assertEquals(expectedInfo, SubscriptionInfo.decode(info.encode()));
    }

    @Test
    public void shouldEncodeAndDecodeVersion4() {
        final SubscriptionInfo info = new SubscriptionInfo(4, processId, activeTasks, standbyTasks, "localhost:80");
        final SubscriptionInfo expectedInfo = new SubscriptionInfo(4, SubscriptionInfo.LATEST_SUPPORTED_VERSION, processId, activeTasks, standbyTasks, "localhost:80");
        assertEquals(expectedInfo, SubscriptionInfo.decode(info.encode()));
    }

    @Test
    public void shouldAllowToDecodeFutureSupportedVersion() {
        final SubscriptionInfo info = SubscriptionInfo.decode(encodeFutureVersion());
        assertEquals(SubscriptionInfo.LATEST_SUPPORTED_VERSION + 1, info.version());
        assertEquals(SubscriptionInfo.LATEST_SUPPORTED_VERSION + 1, info.latestSupportedVersion());
    }

    @Test
    public void shouldEncodeAndDecodeSmallerLatestSupportedVersion() {
        final int usedVersion = SubscriptionInfo.LATEST_SUPPORTED_VERSION - 1;
        final int latestSupportedVersion = SubscriptionInfo.LATEST_SUPPORTED_VERSION - 1;

        final SubscriptionInfo info = new SubscriptionInfo(usedVersion, latestSupportedVersion, processId, activeTasks, standbyTasks, "localhost:80");
        final SubscriptionInfo expectedInfo = new SubscriptionInfo(usedVersion, latestSupportedVersion, processId, activeTasks, standbyTasks, "localhost:80");
        assertEquals(expectedInfo, SubscriptionInfo.decode(info.encode()));
    }

    private ByteBuffer encodeFutureVersion() {
        final ByteBuffer buf = ByteBuffer.allocate(4 /* used version */
                                                   + 4 /* supported version */);
        buf.putInt(SubscriptionInfo.LATEST_SUPPORTED_VERSION + 1);
        buf.putInt(SubscriptionInfo.LATEST_SUPPORTED_VERSION + 1);
        return buf;
    }

}