/**
* 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.net;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.CommonConfigurationKeys;
import org.junit.Assert;
import org.junit.Test;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
/**
* Test the static mapping class.
* Because the map is actually static, this map needs to be reset for every test
*/
public class TestStaticMapping extends Assert {
private static final Log LOG = LogFactory.getLog(TestStaticMapping.class);
/**
* Reset the map then create a new instance of the {@link StaticMapping}
* class with a null configuration
* @return a new instance
*/
private StaticMapping newInstance() {
StaticMapping.resetMap();
return new StaticMapping();
}
/**
* Reset the map then create a new instance of the {@link StaticMapping}
* class with the topology script in the configuration set to
* the parameter
* @param script a (never executed) script, can be null
* @return a new instance
*/
private StaticMapping newInstance(String script) {
StaticMapping mapping = newInstance();
mapping.setConf(createConf(script));
return mapping;
}
/**
* Create a configuration with a specific topology script
* @param script a (never executed) script, can be null
* @return a configuration
*/
private Configuration createConf(String script) {
Configuration conf = new Configuration();
if (script != null) {
conf.set(CommonConfigurationKeys.NET_TOPOLOGY_SCRIPT_FILE_NAME_KEY,
script);
} else {
conf.unset(CommonConfigurationKeys.NET_TOPOLOGY_SCRIPT_FILE_NAME_KEY);
}
return conf;
}
private void assertSingleSwitch(DNSToSwitchMapping mapping) {
assertEquals("Expected a single switch mapping "
+ mapping,
true,
AbstractDNSToSwitchMapping.isMappingSingleSwitch(mapping));
}
private void assertMultiSwitch(DNSToSwitchMapping mapping) {
assertEquals("Expected a multi switch mapping "
+ mapping,
false,
AbstractDNSToSwitchMapping.isMappingSingleSwitch(mapping));
}
protected void assertMapSize(AbstractDNSToSwitchMapping switchMapping, int expectedSize) {
assertEquals(
"Expected two entries in the map " + switchMapping.dumpTopology(),
expectedSize, switchMapping.getSwitchMap().size());
}
private List<String> createQueryList() {
List<String> l1 = new ArrayList<String>(2);
l1.add("n1");
l1.add("unknown");
return l1;
}
@Test
public void testStaticIsSingleSwitchOnNullScript() throws Throwable {
StaticMapping mapping = newInstance(null);
mapping.setConf(createConf(null));
assertSingleSwitch(mapping);
}
@Test
public void testStaticIsMultiSwitchOnScript() throws Throwable {
StaticMapping mapping = newInstance("ls");
assertMultiSwitch(mapping);
}
@Test
public void testAddResolveNodes() throws Throwable {
StaticMapping mapping = newInstance();
StaticMapping.addNodeToRack("n1", "/r1");
List<String> queryList = createQueryList();
List<String> resolved = mapping.resolve(queryList);
assertEquals(2, resolved.size());
assertEquals("/r1", resolved.get(0));
assertEquals(NetworkTopology.DEFAULT_RACK, resolved.get(1));
// get the switch map and examine it
Map<String, String> switchMap = mapping.getSwitchMap();
String topology = mapping.dumpTopology();
LOG.info(topology);
assertEquals(topology, 1, switchMap.size());
assertEquals(topology, "/r1", switchMap.get("n1"));
}
/**
* Verify that a configuration string builds a topology
*/
@Test
public void testReadNodesFromConfig() throws Throwable {
StaticMapping mapping = newInstance();
Configuration conf = new Configuration();
conf.set(StaticMapping.KEY_HADOOP_CONFIGURED_NODE_MAPPING, "n1=/r1,n2=/r2");
mapping.setConf(conf);
//even though we have inserted elements into the list, because
//it is driven by the script key in the configuration, it still
//thinks that it is single rack
assertSingleSwitch(mapping);
List<String> l1 = new ArrayList<String>(3);
l1.add("n1");
l1.add("unknown");
l1.add("n2");
List<String> resolved = mapping.resolve(l1);
assertEquals(3, resolved.size());
assertEquals("/r1", resolved.get(0));
assertEquals(NetworkTopology.DEFAULT_RACK, resolved.get(1));
assertEquals("/r2", resolved.get(2));
Map<String, String> switchMap = mapping.getSwitchMap();
String topology = mapping.dumpTopology();
LOG.info(topology);
assertEquals(topology, 2, switchMap.size());
assertEquals(topology, "/r1", switchMap.get("n1"));
assertNull(topology, switchMap.get("unknown"));
}
/**
* Verify that if the inner mapping is single-switch, so is the cached one
* @throws Throwable on any problem
*/
@Test
public void testCachingRelaysSingleSwitchQueries() throws Throwable {
//create a single switch map
StaticMapping staticMapping = newInstance(null);
assertSingleSwitch(staticMapping);
CachedDNSToSwitchMapping cachedMap =
new CachedDNSToSwitchMapping(staticMapping);
LOG.info("Mapping: " + cachedMap + "\n" + cachedMap.dumpTopology());
assertSingleSwitch(cachedMap);
}
/**
* Verify that if the inner mapping is multi-switch, so is the cached one
* @throws Throwable on any problem
*/
@Test
public void testCachingRelaysMultiSwitchQueries() throws Throwable {
StaticMapping staticMapping = newInstance("top");
assertMultiSwitch(staticMapping);
CachedDNSToSwitchMapping cachedMap =
new CachedDNSToSwitchMapping(staticMapping);
LOG.info("Mapping: " + cachedMap + "\n" + cachedMap.dumpTopology());
assertMultiSwitch(cachedMap);
}
/**
* This test verifies that resultion queries get relayed to the inner rack
* @throws Throwable on any problem
*/
@Test
public void testCachingRelaysResolveQueries() throws Throwable {
StaticMapping mapping = newInstance();
mapping.setConf(createConf("top"));
StaticMapping staticMapping = mapping;
CachedDNSToSwitchMapping cachedMap =
new CachedDNSToSwitchMapping(staticMapping);
assertMapSize(cachedMap, 0);
//add a node to the static map
StaticMapping.addNodeToRack("n1", "/r1");
//verify it is there
assertMapSize(staticMapping, 1);
//verify that the cache hasn't picked it up yet
assertMapSize(cachedMap, 0);
//now relay the query
cachedMap.resolve(createQueryList());
//and verify the cache is no longer empty
assertMapSize(cachedMap, 2);
}
/**
* This test verifies that resultion queries get relayed to the inner rack
* @throws Throwable on any problem
*/
@Test
public void testCachingCachesNegativeEntries() throws Throwable {
StaticMapping staticMapping = newInstance();
CachedDNSToSwitchMapping cachedMap =
new CachedDNSToSwitchMapping(staticMapping);
assertMapSize(cachedMap, 0);
assertMapSize(staticMapping, 0);
List<String> resolved = cachedMap.resolve(createQueryList());
//and verify the cache is no longer empty while the static map is
assertMapSize(staticMapping, 0);
assertMapSize(cachedMap, 2);
}
}