hbase-server/src/test/java/org/apache/hadoop/hbase/coprocessor/TestCoreRegionServerCoprocessor.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.hadoop.hbase.coprocessor;

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

import java.io.IOException;
import org.apache.hadoop.hbase.HBaseClassTestRule;
import org.apache.hadoop.hbase.HBaseTestingUtility;
import org.apache.hadoop.hbase.MockRegionServerServices;
import org.apache.hadoop.hbase.regionserver.RegionServerCoprocessorHost;
import org.apache.hadoop.hbase.regionserver.RegionServerServices;
import org.apache.hadoop.hbase.testclassification.CoprocessorTests;
import org.apache.hadoop.hbase.testclassification.SmallTests;
import org.junit.After;
import org.junit.Before;
import org.junit.ClassRule;
import org.junit.Rule;
import org.junit.Test;
import org.junit.experimental.categories.Category;
import org.junit.rules.TestName;

/**
 * Test CoreCoprocessor Annotation works giving access to facility not usually available.
 * Test RegionServerCoprocessor.
 */
@Category({CoprocessorTests.class, SmallTests.class})
public class TestCoreRegionServerCoprocessor {

  @ClassRule
  public static final HBaseClassTestRule CLASS_RULE =
      HBaseClassTestRule.forClass(TestCoreRegionServerCoprocessor.class);

  @Rule public TestName name = new TestName();
  private static final HBaseTestingUtility HTU = new HBaseTestingUtility();
  private RegionServerServices rss;
  private RegionServerCoprocessorHost rsch;

  @Before
  public void before() throws IOException {
    String methodName = this.name.getMethodName();
    this.rss = new MockRegionServerServices(HTU.getConfiguration());
    this.rsch = new RegionServerCoprocessorHost(this.rss, HTU.getConfiguration());
  }

  @After
  public void after() throws IOException {
    this.rsch.preStop("Stopping", null);
  }

  /**
   * No annotation with CoreCoprocessor. This should make it so I can NOT get at instance of a
   * RegionServerServices instance after some gymnastics.
   */
  public static class NotCoreRegionServerCoprocessor implements RegionServerCoprocessor {
    public NotCoreRegionServerCoprocessor() {}
  }

  /**
   * Annotate with CoreCoprocessor. This should make it so I can get at instance of a
   * RegionServerServices instance after some gymnastics.
   */
  @CoreCoprocessor
  public static class CoreRegionServerCoprocessor implements RegionServerCoprocessor {
    public CoreRegionServerCoprocessor() {}
  }

  /**
   * Assert that when a Coprocessor is annotated with CoreCoprocessor, then it is possible to
   * access a RegionServerServices instance. Assert the opposite too.
   * Do it to RegionServerCoprocessors.
   * @throws IOException
   */
  @Test
  public void testCoreRegionCoprocessor() throws IOException {
    RegionServerCoprocessorEnvironment env =
        rsch.load(null, NotCoreRegionServerCoprocessor.class.getName(), 0, HTU.getConfiguration());
    assertFalse(env instanceof HasRegionServerServices);
    env = rsch.load(null, CoreRegionServerCoprocessor.class.getName(), 1, HTU.getConfiguration());
    assertTrue(env instanceof HasRegionServerServices);
    assertEquals(this.rss, ((HasRegionServerServices)env).getRegionServerServices());
  }
}