server/tracer/src/test/java/org/apache/accumulo/tracer/ZooTraceClientTest.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.accumulo.tracer;

import java.util.concurrent.atomic.AtomicBoolean;

import org.easymock.EasyMock;
import org.junit.Test;

public class ZooTraceClientTest {

  /**
   * An extension on ZooTraceClient which acts as a latch on updateHostsFromZooKeeper using the
   * provided {@link AtomicBoolean}
   */
  private static class UpdateHostsDelegate extends ZooTraceClient {
    private final AtomicBoolean done;

    private UpdateHostsDelegate(AtomicBoolean done) {
      this.done = done;
    }

    @Override
    public void updateHostsFromZooKeeper() {
      this.done.set(true);
    }
  }

  @Test
  public void testConnectFailureRetries() throws Exception {
    ZooTraceClient client = EasyMock.createMockBuilder(ZooTraceClient.class)
        .addMockedMethod("updateHostsFromZooKeeper").createStrictMock();
    client.setRetryPause(0L);
    AtomicBoolean done = new AtomicBoolean(false);

    client.updateHostsFromZooKeeper();
    EasyMock.expectLastCall().andThrow(new RuntimeException()).once();
    client.updateHostsFromZooKeeper();
    // Expect the second call to updateHostsFromZooKeeper, but wait for it to fire before
    // verification
    EasyMock.expectLastCall().andDelegateTo(new UpdateHostsDelegate(done));

    EasyMock.replay(client);

    client.setInitialTraceHosts();

    while (!done.get()) {
      // The 2nd call to updateHostsFromZooKeeper is async. Wait for it for fire before verifying it
      // was called.
      Thread.sleep(200);
    }

    EasyMock.verify(client);

  }

}