heron/io/dlog/tests/java/org/apache/heron/dlog/DLInputStreamTest.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.heron.dlog;

import java.io.ByteArrayInputStream;

import org.junit.Test;

import org.apache.distributedlog.DLSN;
import org.apache.distributedlog.LogRecordWithDLSN;
import org.apache.distributedlog.api.DistributedLogManager;
import org.apache.distributedlog.api.LogReader;
import org.apache.distributedlog.exceptions.EndOfStreamException;

import static com.google.common.base.Charsets.UTF_8;
import static org.junit.Assert.assertEquals;
import static org.mockito.Matchers.any;
import static org.mockito.Matchers.anyBoolean;
import static org.mockito.Matchers.eq;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.times;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.when;

public class DLInputStreamTest {

  /**
   * Test Case: reader hits eos (end of stream)
   */
  @Test
  public void testReadEos() throws Exception {
    DistributedLogManager dlm = mock(DistributedLogManager.class);
    LogReader reader = mock(LogReader.class);
    when(dlm.getInputStream(any(DLSN.class))).thenReturn(reader);
    when(reader.readNext(anyBoolean())).thenThrow(new EndOfStreamException("eos"));

    byte[] b = new byte[1];
    DLInputStream in = new DLInputStream(dlm);
    assertEquals("Should return 0 when reading an empty eos stream",
        -1, in.read(b, 0, 1));
    assertEquals("Should return -1 when reading an empty eos stream",
        -1, in.read(b, 0, 1));
  }

  /**
   * Test Case: close the input stream
   */
  @Test
  public void testClose() throws Exception {
    DistributedLogManager dlm = mock(DistributedLogManager.class);
    LogReader reader = mock(LogReader.class);
    when(dlm.getInputStream(any(DLSN.class))).thenReturn(reader);

    DLInputStream in = new DLInputStream(dlm);
    verify(dlm, times(1)).getInputStream(eq(DLSN.InitialDLSN));
    in.close();
    verify(dlm, times(1)).close();
    verify(reader, times(1)).close();
  }

  /**
   * Test Case: read records from the input stream.
   */
  @Test
  public void testRead() throws Exception {
    DistributedLogManager dlm = mock(DistributedLogManager.class);
    LogReader reader = mock(LogReader.class);
    when(dlm.getInputStream(any(DLSN.class))).thenReturn(reader);

    byte[] data = "test-read".getBytes(UTF_8);
    LogRecordWithDLSN record = mock(LogRecordWithDLSN.class);
    when(record.getPayLoadInputStream())
        .thenReturn(new ByteArrayInputStream(data));
    when(reader.readNext(anyBoolean()))
        .thenReturn(record)
        .thenThrow(new EndOfStreamException("eos"));

    DLInputStream in = new DLInputStream(dlm);
    int numReads = 0;
    int readByte;
    while ((readByte = in.read()) != -1) {
      assertEquals(data[numReads], readByte);
      ++numReads;
    }
    assertEquals(data.length, numReads);
  }

}