DefaultHaDispatchTest.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.gateway.ha.dispatch;

import org.apache.hadoop.gateway.ha.provider.HaDescriptor;
import org.apache.hadoop.gateway.ha.provider.HaProvider;
import org.apache.hadoop.gateway.ha.provider.HaServletContextListener;
import org.apache.hadoop.gateway.ha.provider.impl.DefaultHaProvider;
import org.apache.hadoop.gateway.ha.provider.impl.HaDescriptorFactory;
import org.apache.hadoop.gateway.servlet.SynchronousServletOutputStreamAdapter;
import org.apache.http.client.methods.HttpRequestBase;
import org.apache.http.client.methods.HttpUriRequest;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.params.BasicHttpParams;
import org.easymock.EasyMock;
import org.easymock.IAnswer;
import org.junit.Assert;
import org.junit.Test;

import javax.servlet.FilterConfig;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.net.URI;
import java.util.ArrayList;
import java.util.concurrent.atomic.AtomicInteger;

public class DefaultHaDispatchTest {

  @Test
  public void testConnectivityFailover() throws Exception {
    String serviceName = "OOZIE";
    HaDescriptor descriptor = HaDescriptorFactory.createDescriptor();
    descriptor.addServiceConfig(HaDescriptorFactory.createServiceConfig(serviceName, "true", "1", "1000", "2", "1000", null, null));
    HaProvider provider = new DefaultHaProvider(descriptor);
    URI uri1 = new URI( "http://unreachable-host" );
    URI uri2 = new URI( "http://reachable-host" );
    ArrayList<String> urlList = new ArrayList<String>();
    urlList.add(uri1.toString());
    urlList.add(uri2.toString());
    provider.addHaService(serviceName, urlList);
    FilterConfig filterConfig = EasyMock.createNiceMock(FilterConfig.class);
    ServletContext servletContext = EasyMock.createNiceMock(ServletContext.class);

    EasyMock.expect(filterConfig.getServletContext()).andReturn(servletContext).anyTimes();
    EasyMock.expect(servletContext.getAttribute(HaServletContextListener.PROVIDER_ATTRIBUTE_NAME)).andReturn(provider).anyTimes();

    BasicHttpParams params = new BasicHttpParams();

    HttpUriRequest outboundRequest = EasyMock.createNiceMock(HttpRequestBase.class);
    EasyMock.expect(outboundRequest.getMethod()).andReturn( "GET" ).anyTimes();
    EasyMock.expect(outboundRequest.getURI()).andReturn( uri1  ).anyTimes();
    EasyMock.expect(outboundRequest.getParams()).andReturn( params ).anyTimes();

    HttpServletRequest inboundRequest = EasyMock.createNiceMock(HttpServletRequest.class);
    EasyMock.expect(inboundRequest.getRequestURL()).andReturn( new StringBuffer(uri2.toString()) ).once();
    EasyMock.expect(inboundRequest.getAttribute("dispatch.ha.failover.counter")).andReturn(new AtomicInteger(0)).once();
    EasyMock.expect(inboundRequest.getAttribute("dispatch.ha.failover.counter")).andReturn(new AtomicInteger(1)).once();

    HttpServletResponse outboundResponse = EasyMock.createNiceMock(HttpServletResponse.class);
    EasyMock.expect(outboundResponse.getOutputStream()).andAnswer( new IAnswer<SynchronousServletOutputStreamAdapter>() {
      @Override
      public SynchronousServletOutputStreamAdapter answer() throws Throwable {
        return new SynchronousServletOutputStreamAdapter() {
          @Override
          public void write( int b ) throws IOException {
            throw new IOException( "unreachable-host" );
          }
        };
      }
    }).once();
    EasyMock.replay(filterConfig, servletContext, outboundRequest, inboundRequest, outboundResponse);
    Assert.assertEquals(uri1.toString(), provider.getActiveURL(serviceName));
    DefaultHaDispatch dispatch = new DefaultHaDispatch();
    dispatch.setHttpClient(new DefaultHttpClient());
    dispatch.setHaProvider(provider);
    dispatch.setServiceRole(serviceName);
    dispatch.init();
    long startTime = System.currentTimeMillis();
    try {
      dispatch.executeRequest(outboundRequest, inboundRequest, outboundResponse);
    } catch (IOException e) {
      //this is expected after the failover limit is reached
    }
    long elapsedTime = System.currentTimeMillis() - startTime;
    Assert.assertEquals(uri2.toString(), provider.getActiveURL(serviceName));
    //test to make sure the sleep took place
    Assert.assertTrue(elapsedTime > 1000);
  }
}