TestNetworkTopologyWithNodeGroup.java
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* Licensed to the Apache Software Foundation (ASF) under one
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* 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.net;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;
import java.util.HashMap;
import java.util.Map;
import org.junit.Test;
public class TestNetworkTopologyWithNodeGroup {
private final static NetworkTopologyWithNodeGroup cluster = new
NetworkTopologyWithNodeGroup();
private final static NodeBase dataNodes[] = new NodeBase[] {
new NodeBase("h1", "/d1/r1/s1"),
new NodeBase("h2", "/d1/r1/s1"),
new NodeBase("h3", "/d1/r1/s2"),
new NodeBase("h4", "/d1/r2/s3"),
new NodeBase("h5", "/d1/r2/s3"),
new NodeBase("h6", "/d1/r2/s4"),
new NodeBase("h7", "/d2/r3/s5"),
new NodeBase("h8", "/d2/r3/s6")
};
private final static NodeBase computeNode = new NodeBase("/d1/r1/s1/h9");
private final static NodeBase rackOnlyNode = new NodeBase("h10", "/r2");
static {
for(int i=0; i<dataNodes.length; i++) {
cluster.add(dataNodes[i]);
}
}
@Test
public void testNumOfChildren() throws Exception {
assertEquals(dataNodes.length, cluster.getNumOfLeaves());
}
@Test
public void testNumOfRacks() throws Exception {
assertEquals(3, cluster.getNumOfRacks());
}
@Test
public void testRacks() throws Exception {
assertEquals(3, cluster.getNumOfRacks());
assertTrue(cluster.isOnSameRack(dataNodes[0], dataNodes[1]));
assertTrue(cluster.isOnSameRack(dataNodes[1], dataNodes[2]));
assertFalse(cluster.isOnSameRack(dataNodes[2], dataNodes[3]));
assertTrue(cluster.isOnSameRack(dataNodes[3], dataNodes[4]));
assertTrue(cluster.isOnSameRack(dataNodes[4], dataNodes[5]));
assertFalse(cluster.isOnSameRack(dataNodes[5], dataNodes[6]));
assertTrue(cluster.isOnSameRack(dataNodes[6], dataNodes[7]));
}
@Test
public void testNodeGroups() throws Exception {
assertEquals(3, cluster.getNumOfRacks());
assertTrue(cluster.isOnSameNodeGroup(dataNodes[0], dataNodes[1]));
assertFalse(cluster.isOnSameNodeGroup(dataNodes[1], dataNodes[2]));
assertFalse(cluster.isOnSameNodeGroup(dataNodes[2], dataNodes[3]));
assertTrue(cluster.isOnSameNodeGroup(dataNodes[3], dataNodes[4]));
assertFalse(cluster.isOnSameNodeGroup(dataNodes[4], dataNodes[5]));
assertFalse(cluster.isOnSameNodeGroup(dataNodes[5], dataNodes[6]));
assertFalse(cluster.isOnSameNodeGroup(dataNodes[6], dataNodes[7]));
}
@Test
public void testGetDistance() throws Exception {
assertEquals(0, cluster.getDistance(dataNodes[0], dataNodes[0]));
assertEquals(2, cluster.getDistance(dataNodes[0], dataNodes[1]));
assertEquals(4, cluster.getDistance(dataNodes[0], dataNodes[2]));
assertEquals(6, cluster.getDistance(dataNodes[0], dataNodes[3]));
assertEquals(8, cluster.getDistance(dataNodes[0], dataNodes[6]));
}
@Test
public void testSortByDistance() throws Exception {
NodeBase[] testNodes = new NodeBase[4];
// array contains both local node, local node group & local rack node
testNodes[0] = dataNodes[1];
testNodes[1] = dataNodes[2];
testNodes[2] = dataNodes[3];
testNodes[3] = dataNodes[0];
cluster.sortByDistance(dataNodes[0], testNodes, testNodes.length);
assertTrue(testNodes[0] == dataNodes[0]);
assertTrue(testNodes[1] == dataNodes[1]);
assertTrue(testNodes[2] == dataNodes[2]);
assertTrue(testNodes[3] == dataNodes[3]);
// array contains local node & local node group
testNodes[0] = dataNodes[3];
testNodes[1] = dataNodes[4];
testNodes[2] = dataNodes[1];
testNodes[3] = dataNodes[0];
cluster.sortByDistance(dataNodes[0], testNodes, testNodes.length);
assertTrue(testNodes[0] == dataNodes[0]);
assertTrue(testNodes[1] == dataNodes[1]);
// array contains local node & rack node
testNodes[0] = dataNodes[5];
testNodes[1] = dataNodes[3];
testNodes[2] = dataNodes[2];
testNodes[3] = dataNodes[0];
cluster.sortByDistance(dataNodes[0], testNodes, testNodes.length);
assertTrue(testNodes[0] == dataNodes[0]);
assertTrue(testNodes[1] == dataNodes[2]);
// array contains local-nodegroup node (not a data node also) & rack node
testNodes[0] = dataNodes[6];
testNodes[1] = dataNodes[7];
testNodes[2] = dataNodes[2];
testNodes[3] = dataNodes[0];
cluster.sortByDistance(computeNode, testNodes, testNodes.length);
assertTrue(testNodes[0] == dataNodes[0]);
assertTrue(testNodes[1] == dataNodes[2]);
}
/**
* This picks a large number of nodes at random in order to ensure coverage
*
* @param numNodes the number of nodes
* @param excludedScope the excluded scope
* @return the frequency that nodes were chosen
*/
private Map<Node, Integer> pickNodesAtRandom(int numNodes,
String excludedScope) {
Map<Node, Integer> frequency = new HashMap<Node, Integer>();
for (NodeBase dnd : dataNodes) {
frequency.put(dnd, 0);
}
for (int j = 0; j < numNodes; j++) {
Node random = cluster.chooseRandom(excludedScope);
frequency.put(random, frequency.get(random) + 1);
}
return frequency;
}
/**
* This test checks that chooseRandom works for an excluded node.
*/
/**
* Test replica placement policy in case last node is invalid.
* We create 6 nodes but the last node is in fault topology (with rack info),
* so cannot be added to cluster. We should test proper exception is thrown in
* adding node but shouldn't affect the cluster.
*/
@Test
public void testChooseRandomExcludedNode() {
String scope = "~" + NodeBase.getPath(dataNodes[0]);
Map<Node, Integer> frequency = pickNodesAtRandom(100, scope);
for (Node key : dataNodes) {
// all nodes except the first should be more than zero
assertTrue(frequency.get(key) > 0 || key == dataNodes[0]);
}
}
@Test
public void testNodeGroup() throws Exception {
String res = cluster.getNodeGroup("");
assertTrue("NodeGroup should be NodeBase.ROOT for empty location",
res.equals(NodeBase.ROOT));
try {
cluster.getNodeGroup(null);
} catch (IllegalArgumentException e) {
assertTrue("Null Network Location should throw exception!",
e.getMessage().contains("Network Location is null"));
}
}
/**
* This test checks that adding a node with invalid topology will be failed
* with an exception to show topology is invalid.
*/
@Test
public void testAddNodeWithInvalidTopology() {
// The last node is a node with invalid topology
try {
cluster.add(rackOnlyNode);
fail("Exception should be thrown, so we should not have reached here.");
} catch (Exception e) {
if (!(e instanceof IllegalArgumentException)) {
fail("Expecting IllegalArgumentException, but caught:" + e);
}
assertTrue(e.getMessage().contains("illegal network location"));
}
}
}