YARN-6815. FederationStateStoreFacade return behavior should be consistent irrespective of whether caching is enabled or not.

(cherry picked from commit 8820693cd769065eed83193b673ec5d919d69500)

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-common/src/main/java/org/apache/hadoop/yarn/server/federation/policies/RouterPolicyFacade.java

@@ -23,13 +23,10 @@
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.yarn.api.records.ApplicationSubmissionContext;
 import org.apache.hadoop.yarn.conf.YarnConfiguration;
 import org.apache.hadoop.yarn.exceptions.YarnException;
-import org.apache.hadoop.yarn.server.federation.policies.amrmproxy.LocalityMulticastAMRMProxyPolicy;
 import org.apache.hadoop.yarn.server.federation.policies.exceptions.FederationPolicyException;
 import org.apache.hadoop.yarn.server.federation.policies.exceptions.FederationPolicyInitializationException;
 import org.apache.hadoop.yarn.server.federation.policies.manager.FederationPolicyManager;
@@ -38,6 +35,8 @@
 import org.apache.hadoop.yarn.server.federation.store.records.SubClusterId;
 import org.apache.hadoop.yarn.server.federation.store.records.SubClusterPolicyConfiguration;
 import org.apache.hadoop.yarn.server.federation.utils.FederationStateStoreFacade;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import com.google.common.annotations.VisibleForTesting;
 
@@ -47,8 +46,8 @@
  */
 public class RouterPolicyFacade {
 
-  private static final Log LOG =
+  private static final Logger LOG =
-      LogFactory.getLog(LocalityMulticastAMRMProxyPolicy.class);
+      LoggerFactory.getLogger(RouterPolicyFacade.class);
 
   private final SubClusterResolver subClusterResolver;
   private final FederationStateStoreFacade federationFacade;
@@ -68,10 +67,10 @@ public RouterPolicyFacade(Configuration conf,
     this.globalPolicyMap = new ConcurrentHashMap<>();
 
     // load default behavior from store if possible
-    String defaulKey = YarnConfiguration.DEFAULT_FEDERATION_POLICY_KEY;
+    String defaultKey = YarnConfiguration.DEFAULT_FEDERATION_POLICY_KEY;
     SubClusterPolicyConfiguration configuration = null;
     try {
-      configuration = federationFacade.getPolicyConfiguration(defaulKey);
+      configuration = federationFacade.getPolicyConfiguration(defaultKey);
     } catch (YarnException e) {
       LOG.warn("No fallback behavior defined in store, defaulting to XML "
           + "configuration fallback behavior.");
@@ -88,7 +87,7 @@ public RouterPolicyFacade(Configuration conf,
       ByteBuffer defaultPolicyParam = ByteBuffer
           .wrap(defaultPolicyParamString.getBytes(StandardCharsets.UTF_8));
 
-      configuration = SubClusterPolicyConfiguration.newInstance(defaulKey,
+      configuration = SubClusterPolicyConfiguration.newInstance(defaultKey,
           defaultFederationPolicyManager, defaultPolicyParam);
     }
 
@@ -98,12 +97,12 @@ public RouterPolicyFacade(Configuration conf,
             subClusterResolver, federationFacade, homeSubcluster);
     FederationPolicyManager fallbackPolicyManager =
         FederationPolicyUtils.instantiatePolicyManager(configuration.getType());
-    fallbackPolicyManager.setQueue(defaulKey);
+    fallbackPolicyManager.setQueue(defaultKey);
 
     // add to the cache the fallback behavior
-    globalConfMap.put(defaulKey,
+    globalConfMap.put(defaultKey,
         fallbackContext.getSubClusterPolicyConfiguration());
-    globalPolicyMap.put(defaulKey,
+    globalPolicyMap.put(defaultKey,
         fallbackPolicyManager.getRouterPolicy(fallbackContext, null));
 
   }
@@ -155,28 +154,36 @@ public SubClusterId getHomeSubcluster(
     try {
       configuration = federationFacade.getPolicyConfiguration(queue);
     } catch (YarnException e) {
-      LOG.debug(e);
+      String errMsg = "There is no policy configured for the queue: " + queue
+          + ", falling back to defaults.";
+      LOG.warn(errMsg, e);
     }
 
     // If there is no policy configured for this queue, fallback to the baseline
     // policy that is configured either in the store or via XML config (and
     // cached)
     if (configuration == null) {
-      try {
       LOG.warn("There is no policies configured for queue: " + queue + " we"
           + " fallback to default policy for: "
           + YarnConfiguration.DEFAULT_FEDERATION_POLICY_KEY);
 
       queue = YarnConfiguration.DEFAULT_FEDERATION_POLICY_KEY;
-        configuration = federationFacade.getPolicyConfiguration(
+      try {
-            YarnConfiguration.DEFAULT_FEDERATION_POLICY_KEY);
+        configuration = federationFacade.getPolicyConfiguration(queue);
       } catch (YarnException e) {
+        String errMsg = "Cannot retrieve policy configured for the queue: "
+            + queue + ", falling back to defaults.";
+        LOG.warn(errMsg, e);
+
+      }
+    }
+
     // the fallback is not configure via store, but via XML, using
     // previously loaded configuration.
+    if (configuration == null) {
       configuration =
           cachedConfs.get(YarnConfiguration.DEFAULT_FEDERATION_POLICY_KEY);
     }
-    }
 
     // if the configuration has changed since last loaded, reinit the policy
     // based on current configuration

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-common/src/main/java/org/apache/hadoop/yarn/server/federation/store/FederationMembershipStateStore.java

@@ -94,7 +94,8 @@ SubClusterHeartbeatResponse subClusterHeartbeat(
    * endpoint and current capabilities as represented by {@code SubClusterInfo}.
    *
    * @param subClusterRequest the subcluster whose information is required
-   * @return the {@code SubClusterInfo}
+   * @return the {@code SubClusterInfo}, or {@code null} if there is no mapping
+   *         for the subcluster
    * @throws YarnException if the request is invalid/fails
    */
   GetSubClusterInfoResponse getSubCluster(

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-common/src/main/java/org/apache/hadoop/yarn/server/federation/store/FederationPolicyStore.java

@@ -45,7 +45,8 @@ public interface FederationPolicyStore {
    *
    * @param request the queue whose {@code SubClusterPolicyConfiguration} is
    *          required
-   * @return the {@code SubClusterPolicyConfiguration} for the specified queue
+   * @return the {@code SubClusterPolicyConfiguration} for the specified queue,
+   *         or {@code null} if there is no mapping for the queue
    * @throws YarnException if the request is invalid/fails
    */
   GetSubClusterPolicyConfigurationResponse getPolicyConfiguration(

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-common/src/main/java/org/apache/hadoop/yarn/server/federation/store/impl/MemoryFederationStateStore.java

@@ -165,9 +165,8 @@ public GetSubClusterInfoResponse getSubCluster(
     FederationMembershipStateStoreInputValidator.validate(request);
     SubClusterId subClusterId = request.getSubClusterId();
     if (!membership.containsKey(subClusterId)) {
-      String errMsg =
+      LOG.warn("The queried SubCluster: {} does not exist.", subClusterId);
-          "SubCluster " + subClusterId.toString() + " does not exist";
+      return null;
-      FederationStateStoreUtils.logAndThrowStoreException(LOG, errMsg);
     }
 
     return GetSubClusterInfoResponse.newInstance(membership.get(subClusterId));
@@ -274,8 +273,8 @@ public GetSubClusterPolicyConfigurationResponse getPolicyConfiguration(
     FederationPolicyStoreInputValidator.validate(request);
     String queue = request.getQueue();
     if (!policies.containsKey(queue)) {
-      String errMsg = "Policy for queue " + queue + " does not exist";
+      LOG.warn("Policy for queue: {} does not exist.", queue);
-      FederationStateStoreUtils.logAndThrowStoreException(LOG, errMsg);
+      return null;
     }
 
     return GetSubClusterPolicyConfigurationResponse

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-common/src/main/java/org/apache/hadoop/yarn/server/federation/store/impl/SQLFederationStateStore.java

@@ -385,6 +385,12 @@ public GetSubClusterInfoResponse getSubCluster(
       String rmAdminAddress = cstmt.getString(4);
       String webAppAddress = cstmt.getString(5);
 
+      // first check if the subCluster exists
+      if((amRMAddress == null) || (clientRMAddress == null)) {
+        LOG.warn("The queried SubCluster: {} does not exist.", subClusterId);
+        return null;
+      }
+
       Timestamp heartBeatTimeStamp = cstmt.getTimestamp(6, utcCalendar);
       long lastHeartBeat =
           heartBeatTimeStamp != null ? heartBeatTimeStamp.getTime() : 0;
@@ -788,9 +794,8 @@ public GetSubClusterPolicyConfigurationResponse getPolicyConfiguration(
               + subClusterPolicyConfiguration.toString());
         }
       } else {
-        String errMsg =
+        LOG.warn("Policy for queue: {} does not exist.", request.getQueue());
-            "Policy for queue " + request.getQueue() + " does not exist";
+        return null;
-        FederationStateStoreUtils.logAndThrowStoreException(LOG, errMsg);
       }
 
     } catch (SQLException e) {

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-common/src/main/java/org/apache/hadoop/yarn/server/federation/utils/FederationStateStoreFacade.java

@@ -55,6 +55,7 @@
 import org.apache.hadoop.yarn.server.federation.store.records.GetApplicationHomeSubClusterRequest;
 import org.apache.hadoop.yarn.server.federation.store.records.GetApplicationHomeSubClusterResponse;
 import org.apache.hadoop.yarn.server.federation.store.records.GetSubClusterInfoRequest;
+import org.apache.hadoop.yarn.server.federation.store.records.GetSubClusterInfoResponse;
 import org.apache.hadoop.yarn.server.federation.store.records.GetSubClusterPoliciesConfigurationsRequest;
 import org.apache.hadoop.yarn.server.federation.store.records.GetSubClusterPoliciesConfigurationsResponse;
 import org.apache.hadoop.yarn.server.federation.store.records.GetSubClusterPolicyConfigurationRequest;
@@ -221,7 +222,8 @@ public static FederationStateStoreFacade getInstance() {
    * Returns the {@link SubClusterInfo} for the specified {@link SubClusterId}.
    *
    * @param subClusterId the identifier of the sub-cluster
-   * @return the sub cluster information
+   * @return the sub cluster information, or
+   *         {@code null} if there is no mapping for the subClusterId
    * @throws YarnException if the call to the state store is unsuccessful
    */
   public SubClusterInfo getSubCluster(final SubClusterId subClusterId)
@@ -229,9 +231,13 @@ public SubClusterInfo getSubCluster(final SubClusterId subClusterId)
     if (isCachingEnabled()) {
       return getSubClusters(false).get(subClusterId);
     } else {
-      return stateStore
+      GetSubClusterInfoResponse response = stateStore
-          .getSubCluster(GetSubClusterInfoRequest.newInstance(subClusterId))
+          .getSubCluster(GetSubClusterInfoRequest.newInstance(subClusterId));
-          .getSubClusterInfo();
+      if (response == null) {
+        return null;
+      } else {
+        return response.getSubClusterInfo();
+      }
     }
   }
 
@@ -282,7 +288,8 @@ public Map<SubClusterId, SubClusterInfo> getSubClusters(
    * Returns the {@link SubClusterPolicyConfiguration} for the specified queue.
    *
    * @param queue the queue whose policy is required
-   * @return the corresponding configured policy
+   * @return the corresponding configured policy, or {@code null} if there is no
+   *         mapping for the queue
    * @throws YarnException if the call to the state store is unsuccessful
    */
   public SubClusterPolicyConfiguration getPolicyConfiguration(
@@ -295,8 +302,7 @@ public SubClusterPolicyConfiguration getPolicyConfiguration(
           stateStore.getPolicyConfiguration(
               GetSubClusterPolicyConfigurationRequest.newInstance(queue));
       if (response == null) {
-        throw new YarnException("The stateStore returned a null for "
+        return null;
-            + "GetSubClusterPolicyConfigurationResponse for queue " + queue);
       } else {
         return response.getPolicyConfiguration();
       }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-common/src/test/java/org/apache/hadoop/yarn/server/federation/store/impl/FederationStateStoreBaseTest.java

@@ -38,6 +38,7 @@
 import org.apache.hadoop.yarn.server.federation.store.records.GetApplicationsHomeSubClusterRequest;
 import org.apache.hadoop.yarn.server.federation.store.records.GetApplicationsHomeSubClusterResponse;
 import org.apache.hadoop.yarn.server.federation.store.records.GetSubClusterInfoRequest;
+import org.apache.hadoop.yarn.server.federation.store.records.GetSubClusterInfoResponse;
 import org.apache.hadoop.yarn.server.federation.store.records.GetSubClusterPoliciesConfigurationsRequest;
 import org.apache.hadoop.yarn.server.federation.store.records.GetSubClusterPoliciesConfigurationsResponse;
 import org.apache.hadoop.yarn.server.federation.store.records.GetSubClusterPolicyConfigurationRequest;
@@ -157,13 +158,8 @@ public void testGetSubClusterInfoUnknownSubCluster() throws Exception {
     GetSubClusterInfoRequest request =
         GetSubClusterInfoRequest.newInstance(subClusterId);
 
-    try {
+    GetSubClusterInfoResponse response = stateStore.getSubCluster(request);
-      stateStore.getSubCluster(request).getSubClusterInfo();
+    Assert.assertNull(response);
-      Assert.fail();
-    } catch (FederationStateStoreException e) {
-      Assert.assertTrue(
-          e.getMessage().startsWith("SubCluster SC does not exist"));
-    }
   }
 
   @Test
@@ -473,13 +469,10 @@ public void testGetPolicyConfigurationUnknownQueue() throws Exception {
 
     GetSubClusterPolicyConfigurationRequest request =
         GetSubClusterPolicyConfigurationRequest.newInstance("Queue");
-    try {
+
+    GetSubClusterPolicyConfigurationResponse response =
         stateStore.getPolicyConfiguration(request);
-      Assert.fail();
+    Assert.assertNull(response);
-    } catch (FederationStateStoreException e) {
-      Assert.assertTrue(
-          e.getMessage().startsWith("Policy for queue Queue does not exist"));
-    }
   }
 
   @Test

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-common/src/test/java/org/apache/hadoop/yarn/server/federation/utils/FederationStateStoreTestUtil.java

@@ -51,6 +51,7 @@ public class FederationStateStoreTestUtil {
   public static final String SC_PREFIX = "SC-";
   public static final String Q_PREFIX = "queue-";
   public static final String POLICY_PREFIX = "policy-";
+  public static final String INVALID = "dummy";
 
   private FederationStateStore stateStore;
 

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-common/src/test/java/org/apache/hadoop/yarn/server/federation/utils/TestFederationStateStoreFacade.java

@@ -47,6 +47,7 @@
 public class TestFederationStateStoreFacade {
 
   @Parameters
+  @SuppressWarnings({"NoWhitespaceAfter"})
   public static Collection<Boolean[]> getParameters() {
     return Arrays
         .asList(new Boolean[][] { { Boolean.FALSE }, { Boolean.TRUE } });
@@ -98,6 +99,13 @@ public void testGetSubCluster() throws YarnException {
     }
   }
 
+  @Test
+  public void testInvalidGetSubCluster() throws YarnException {
+    SubClusterId subClusterId =
+        SubClusterId.newInstance(FederationStateStoreTestUtil.INVALID);
+    Assert.assertNull(facade.getSubCluster(subClusterId));
+  }
+
   @Test
   public void testGetSubClusterFlushCache() throws YarnException {
     for (int i = 0; i < numSubClusters; i++) {
@@ -127,6 +135,12 @@ public void testGetPolicyConfiguration() throws YarnException {
     }
   }
 
+  @Test
+  public void testInvalidGetPolicyConfiguration() throws YarnException {
+    Assert.assertNull(
+        facade.getPolicyConfiguration(FederationStateStoreTestUtil.INVALID));
+  }
+
   @Test
   public void testGetPoliciesConfigurations() throws YarnException {
     Map<String, SubClusterPolicyConfiguration> queuePolicies =