YARN-9655. AllocateResponse in FederationInterceptor lost applicationPriority. Contributed by hunshenshi.

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/amrmproxy/FederationInterceptor.java

@@ -1446,6 +1446,11 @@ public class FederationInterceptor extends AbstractRequestInterceptor {
       }
     }
 
+    if (otherResponse.getApplicationPriority() != null) {
+      homeResponse.setApplicationPriority(
+          otherResponse.getApplicationPriority());
+    }
+
     homeResponse.setNumClusterNodes(
         homeResponse.getNumClusterNodes() + otherResponse.getNumClusterNodes());
 

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/test/java/org/apache/hadoop/yarn/server/nodemanager/amrmproxy/TestFederationInterceptor.java

@@ -748,6 +748,7 @@ public class TestFederationInterceptor extends BaseAMRMProxyTest {
     Assert.assertEquals(1, response.getNMTokens().size());
     Assert.assertEquals(1, response.getUpdatedContainers().size());
     Assert.assertEquals(1, response.getUpdateErrors().size());
+    Assert.assertNotNull(response.getApplicationPriority());
   }
 
   @Test