YARN-9140. Code cleanup in ResourcePluginManager.initialize and in TestResourcePluginManager. Contributed by Peter Bacsko

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/containermanager/resourceplugin/ResourcePluginManager.java

@@ -19,6 +19,7 @@
 package org.apache.hadoop.yarn.server.nodemanager.containermanager.resourceplugin;
 
 import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.Maps;
 import org.apache.commons.lang3.StringUtils;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.yarn.conf.YarnConfiguration;
@@ -33,7 +34,6 @@ import org.slf4j.LoggerFactory;
 
 import java.util.Arrays;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.Map;
 import java.util.Set;
 
@@ -56,6 +56,17 @@ public class ResourcePluginManager {
       throws YarnException {
     Configuration conf = context.getConf();
 
+    String[] plugins = getPluginsFromConfig(conf);
+
+    Map<String, ResourcePlugin> pluginMap = Maps.newHashMap();
+    if (plugins != null) {
+      pluginMap = initializePlugins(context, plugins);
+    }
+
+    configuredPlugins = Collections.unmodifiableMap(pluginMap);
+  }
+
+  private String[] getPluginsFromConfig(Configuration conf) {
     String[] plugins = conf.getStrings(YarnConfiguration.NM_RESOURCE_PLUGINS);
     if (plugins == null || plugins.length == 0) {
       LOG.info("No Resource plugins found from configuration!");
@@ -63,27 +74,19 @@ public class ResourcePluginManager {
     LOG.info("Found Resource plugins from configuration: "
         + Arrays.toString(plugins));
 
-    if (plugins != null) {
-      Map<String, ResourcePlugin> pluginMap = new HashMap<>();
-
-      // Initialize each plugins
-      for (String resourceName : plugins) {
-        resourceName = resourceName.trim();
-        if (!SUPPORTED_RESOURCE_PLUGINS.contains(resourceName)) {
-          String msg =
-              "Trying to initialize resource plugin with name=" + resourceName
-                  + ", it is not supported, list of supported plugins:"
-                  + StringUtils.join(",", SUPPORTED_RESOURCE_PLUGINS);
-          LOG.error(msg);
-          throw new YarnException(msg);
-        }
+    return plugins;
+  }
 
-        if (pluginMap.containsKey(resourceName)) {
-          LOG.warn("Ignoring duplicate Resource plugin definition: " +
-              resourceName);
-          continue;
-        }
 
+  private Map<String, ResourcePlugin> initializePlugins(
+      Context context, String[] plugins) throws YarnException {
+    Map<String, ResourcePlugin> pluginMap = Maps.newHashMap();
+
+    for (String resourceName : plugins) {
+      resourceName = resourceName.trim();
+      ensurePluginIsSupported(resourceName);
+
+      if (!isPluginDuplicate(pluginMap, resourceName)) {
         ResourcePlugin plugin = null;
         if (resourceName.equals(GPU_URI)) {
           final GpuDiscoverer gpuDiscoverer = new GpuDiscoverer();
@@ -103,11 +106,33 @@ public class ResourcePluginManager {
         LOG.info("Initialized plugin {}", plugin);
         pluginMap.put(resourceName, plugin);
       }
+    }
+    return pluginMap;
+  }
 
-      configuredPlugins = Collections.unmodifiableMap(pluginMap);
+  private void ensurePluginIsSupported(String resourceName)
+      throws YarnException {
+    if (!SUPPORTED_RESOURCE_PLUGINS.contains(resourceName)) {
+      String msg =
+          "Trying to initialize resource plugin with name=" + resourceName
+              + ", it is not supported, list of supported plugins:"
+              + StringUtils.join(",", SUPPORTED_RESOURCE_PLUGINS);
+      LOG.error(msg);
+      throw new YarnException(msg);
     }
   }
 
+  private boolean isPluginDuplicate(Map<String, ResourcePlugin> pluginMap,
+      String resourceName) {
+    if (pluginMap.containsKey(resourceName)) {
+      LOG.warn("Ignoring duplicate Resource plugin definition: " +
+          resourceName);
+      return true;
+    }
+    return false;
+  }
+
+
   public void cleanup() throws YarnException {
     for (ResourcePlugin plugin : configuredPlugins.values()) {
       plugin.cleanup();

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/test/java/org/apache/hadoop/yarn/server/nodemanager/containermanager/resourceplugin/TestResourcePluginManager.java

@@ -40,10 +40,6 @@ import org.apache.hadoop.yarn.server.nodemanager.containermanager.linux.privileg
 import org.apache.hadoop.yarn.server.nodemanager.containermanager.linux.resources.CGroupsHandler;
 import org.apache.hadoop.yarn.server.nodemanager.containermanager.linux.resources.ResourceHandler;
 import org.apache.hadoop.yarn.server.nodemanager.containermanager.linux.resources.ResourceHandlerChain;
-import org.apache.hadoop.yarn.server.nodemanager.containermanager.linux.resources.ResourceHandlerException;
-import org.apache.hadoop.yarn.server.nodemanager.containermanager.resourceplugin.NodeResourceUpdaterPlugin;
-import org.apache.hadoop.yarn.server.nodemanager.containermanager.resourceplugin.ResourcePlugin;
-import org.apache.hadoop.yarn.server.nodemanager.containermanager.resourceplugin.ResourcePluginManager;
 import org.apache.hadoop.yarn.server.security.ApplicationACLsManager;
 import org.junit.After;
 import org.junit.Assert;
@@ -55,10 +51,11 @@ import java.util.Map;
 
 import static org.mockito.Matchers.any;
 import static org.mockito.Mockito.mock;
-import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
+import java.io.IOException;
+
 public class TestResourcePluginManager extends NodeManagerTestBase {
   private NodeManager nm;
 
@@ -99,38 +96,33 @@ public class TestResourcePluginManager extends NodeManagerTestBase {
   private class CustomizedResourceHandler implements ResourceHandler {
 
     @Override
-    public List<PrivilegedOperation> bootstrap(Configuration configuration)
-        throws ResourceHandlerException {
+    public List<PrivilegedOperation> bootstrap(Configuration configuration) {
       return null;
     }
 
     @Override
-    public List<PrivilegedOperation> preStart(Container container)
-        throws ResourceHandlerException {
+    public List<PrivilegedOperation> preStart(Container container) {
       return null;
     }
 
     @Override
-    public List<PrivilegedOperation> reacquireContainer(ContainerId containerId)
-        throws ResourceHandlerException {
+    public List<PrivilegedOperation> reacquireContainer(
+        ContainerId containerId) {
       return null;
     }
 
     @Override
-    public List<PrivilegedOperation> updateContainer(Container container)
-        throws ResourceHandlerException {
+    public List<PrivilegedOperation> updateContainer(Container container) {
       return null;
     }
 
     @Override
-    public List<PrivilegedOperation> postComplete(ContainerId containerId)
-        throws ResourceHandlerException {
+    public List<PrivilegedOperation> postComplete(ContainerId containerId) {
       return null;
     }
 
     @Override
-    public List<PrivilegedOperation> teardown()
-        throws ResourceHandlerException {
+    public List<PrivilegedOperation> teardown() {
       return null;
     }
   }
@@ -155,9 +147,9 @@ public class TestResourcePluginManager extends NodeManagerTestBase {
         ContainerExecutor exec, DeletionService del,
         NodeStatusUpdater nodeStatusUpdater,
         ApplicationACLsManager aclsManager,
-        LocalDirsHandlerService diskhandler) {
+        LocalDirsHandlerService dirsHandler) {
       return new MyContainerManager(context, exec, del, nodeStatusUpdater,
-      metrics, diskhandler);
+      metrics, dirsHandler);
     }
 
     @Override
@@ -185,7 +177,7 @@ public class TestResourcePluginManager extends NodeManagerTestBase {
 
     YarnConfiguration conf = createNMConfig();
     nm.init(conf);
-    verify(rpm, times(1)).initialize(
+    verify(rpm).initialize(
         any(Context.class));
   }
 
@@ -206,15 +198,17 @@ public class TestResourcePluginManager extends NodeManagerTestBase {
         rpm.getNameToPlugins().get("resource1")
             .getNodeResourceHandlerInstance();
 
-    verify(nodeResourceUpdaterPlugin, times(1)).updateConfiguredResource(
-        any(Resource.class));
+
+    verify(nodeResourceUpdaterPlugin)
+        .updateConfiguredResource(any(Resource.class));
   }
 
   /*
    * Make sure ResourcePluginManager is used to initialize ResourceHandlerChain
    */
   @Test(timeout = 30000)
-  public void testLinuxContainerExecutorWithResourcePluginsEnabled() throws Exception {
+  public void testLinuxContainerExecutorWithResourcePluginsEnabled()
+      throws IOException {
     final ResourcePluginManager rpm = stubResourcePluginmanager();
     final LinuxContainerExecutor lce = new MyLCE();
 
@@ -223,8 +217,8 @@ public class TestResourcePluginManager extends NodeManagerTestBase {
       protected NodeStatusUpdater createNodeStatusUpdater(Context context,
           Dispatcher dispatcher, NodeHealthCheckerService healthChecker) {
         ((NMContext)context).setResourcePluginManager(rpm);
-        return new BaseNodeStatusUpdaterForTest(context, dispatcher, healthChecker,
-            metrics, new BaseResourceTrackerForTest());
+        return new BaseNodeStatusUpdaterForTest(context, dispatcher,
+            healthChecker, metrics, new BaseResourceTrackerForTest());
       }
 
       @Override
@@ -232,9 +226,9 @@ public class TestResourcePluginManager extends NodeManagerTestBase {
           ContainerExecutor exec, DeletionService del,
           NodeStatusUpdater nodeStatusUpdater,
           ApplicationACLsManager aclsManager,
-          LocalDirsHandlerService diskhandler) {
+          LocalDirsHandlerService dirsHandler) {
         return new MyContainerManager(context, exec, del, nodeStatusUpdater,
-            metrics, diskhandler);
+            metrics, dirsHandler);
       }
 
       @Override