streams/src/test/java/org/apache/kafka/streams/kstream/internals/KTableSourceTest.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.
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package org.apache.kafka.streams.kstream.internals;

import org.apache.kafka.common.serialization.Serde;
import org.apache.kafka.common.serialization.Serdes;
import org.apache.kafka.common.utils.Utils;
import org.apache.kafka.streams.kstream.KStreamBuilder;
import org.apache.kafka.streams.kstream.KTable;
import org.apache.kafka.test.KStreamTestDriver;
import org.apache.kafka.test.MockProcessorSupplier;
import org.apache.kafka.test.TestUtils;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

import java.io.File;
import java.io.IOException;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNull;
import static org.junit.Assert.assertTrue;

public class KTableSourceTest {

    final private Serde<String> stringSerde = Serdes.String();

    private KStreamTestDriver driver = null;
    private File stateDir = null;

    @After
    public void tearDown() {
        if (driver != null) {
            driver.close();
        }
        driver = null;
    }

    @Before
    public void setUp() throws IOException {
        stateDir = TestUtils.tempDirectory("kafka-test");
    }

    @Test
    public void testKTable() {
        final KStreamBuilder builder = new KStreamBuilder();

        String topic1 = "topic1";

        KTable<String, String> table1 = builder.table(stringSerde, stringSerde, topic1);

        MockProcessorSupplier<String, String> proc1 = new MockProcessorSupplier<>();
        table1.toStream().process(proc1);

        driver = new KStreamTestDriver(builder);

        driver.process(topic1, "A", 1);
        driver.process(topic1, "B", 2);
        driver.process(topic1, "C", 3);
        driver.process(topic1, "D", 4);
        driver.process(topic1, "A", null);
        driver.process(topic1, "B", null);

        assertEquals(Utils.mkList("A:1", "B:2", "C:3", "D:4", "A:null", "B:null"), proc1.processed);
    }

    @Test
    public void testValueGetter() throws IOException {
        final KStreamBuilder builder = new KStreamBuilder();

        String topic1 = "topic1";

        KTableImpl<String, String, String> table1 = (KTableImpl<String, String, String>) builder.table(stringSerde, stringSerde, topic1);

        KTableValueGetterSupplier<String, String> getterSupplier1 = table1.valueGetterSupplier();

        driver = new KStreamTestDriver(builder, stateDir, null, null);

        KTableValueGetter<String, String> getter1 = getterSupplier1.get();
        getter1.init(driver.context());

        driver.process(topic1, "A", "01");
        driver.process(topic1, "B", "01");
        driver.process(topic1, "C", "01");

        assertEquals("01", getter1.get("A"));
        assertEquals("01", getter1.get("B"));
        assertEquals("01", getter1.get("C"));

        driver.process(topic1, "A", "02");
        driver.process(topic1, "B", "02");

        assertEquals("02", getter1.get("A"));
        assertEquals("02", getter1.get("B"));
        assertEquals("01", getter1.get("C"));

        driver.process(topic1, "A", "03");

        assertEquals("03", getter1.get("A"));
        assertEquals("02", getter1.get("B"));
        assertEquals("01", getter1.get("C"));

        driver.process(topic1, "A", null);
        driver.process(topic1, "B", null);

        assertNull(getter1.get("A"));
        assertNull(getter1.get("B"));
        assertEquals("01", getter1.get("C"));

    }

    @Test
    public void testNotSedingOldValue() throws IOException {
        final KStreamBuilder builder = new KStreamBuilder();

        String topic1 = "topic1";

        KTableImpl<String, String, String> table1 = (KTableImpl<String, String, String>) builder.table(stringSerde, stringSerde, topic1);

        MockProcessorSupplier<String, Integer> proc1 = new MockProcessorSupplier<>();

        builder.addProcessor("proc1", proc1, table1.name);

        driver = new KStreamTestDriver(builder, stateDir, null, null);

        driver.process(topic1, "A", "01");
        driver.process(topic1, "B", "01");
        driver.process(topic1, "C", "01");

        proc1.checkAndClearProcessResult("A:(01<-null)", "B:(01<-null)", "C:(01<-null)");

        driver.process(topic1, "A", "02");
        driver.process(topic1, "B", "02");

        proc1.checkAndClearProcessResult("A:(02<-null)", "B:(02<-null)");

        driver.process(topic1, "A", "03");

        proc1.checkAndClearProcessResult("A:(03<-null)");

        driver.process(topic1, "A", null);
        driver.process(topic1, "B", null);

        proc1.checkAndClearProcessResult("A:(null<-null)", "B:(null<-null)");
    }

    @Test
    public void testSedingOldValue() throws IOException {
        final KStreamBuilder builder = new KStreamBuilder();

        String topic1 = "topic1";

        KTableImpl<String, String, String> table1 = (KTableImpl<String, String, String>) builder.table(stringSerde, stringSerde, topic1);

        table1.enableSendingOldValues();

        assertTrue(table1.sendingOldValueEnabled());

        MockProcessorSupplier<String, Integer> proc1 = new MockProcessorSupplier<>();

        builder.addProcessor("proc1", proc1, table1.name);

        driver = new KStreamTestDriver(builder, stateDir, null, null);

        driver.process(topic1, "A", "01");
        driver.process(topic1, "B", "01");
        driver.process(topic1, "C", "01");

        proc1.checkAndClearProcessResult("A:(01<-null)", "B:(01<-null)", "C:(01<-null)");

        driver.process(topic1, "A", "02");
        driver.process(topic1, "B", "02");

        proc1.checkAndClearProcessResult("A:(02<-01)", "B:(02<-01)");

        driver.process(topic1, "A", "03");

        proc1.checkAndClearProcessResult("A:(03<-02)");

        driver.process(topic1, "A", null);
        driver.process(topic1, "B", null);

        proc1.checkAndClearProcessResult("A:(null<-03)", "B:(null<-02)");
    }
}