HDFS-17746. [ARR] The behavior of throwing exception in getListing should be consistent with sync mode. (#7464). Contributed by hfutatzhanghb.

Reviewed-by: Jian Zhang <keepromise@apache.org>
Signed-off-by: He Xiaoqiao <hexiaoqiao@apache.org>

hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/async/RouterAsyncClientProtocol.java

@@ -526,25 +526,24 @@ public class RouterAsyncClientProtocol extends RouterClientProtocol {
   @Override
   protected List<RemoteResult<RemoteLocation, DirectoryListing>> getListingInt(
       String src, byte[] startAfter, boolean needLocation) throws IOException {
-    List<RemoteLocation> locations =
-        rpcServer.getLocationsForPath(src, false, false);
-    // Locate the dir and fetch the listing.
-    if (locations.isEmpty()) {
-      asyncComplete(new ArrayList<>());
-      return asyncReturn(List.class);
-    }
-    asyncTry(() -> {
+    try {
+      List<RemoteLocation> locations =
+          rpcServer.getLocationsForPath(src, false, false);
+      // Locate the dir and fetch the listing.
+      if (locations.isEmpty()) {
+        asyncComplete(new ArrayList<>());
+        return asyncReturn(List.class);
+      }
       RemoteMethod method = new RemoteMethod("getListing",
           new Class<?>[] {String.class, startAfter.getClass(), boolean.class},
           new RemoteParam(), startAfter, needLocation);
       rpcClient.invokeConcurrent(locations, method, false, -1,
           DirectoryListing.class);
-    });
-    asyncCatch((CatchFunction<List, RouterResolveException>) (o, e) -> {
+    } catch (NoLocationException | RouterResolveException e) {
       LOG.debug("Cannot get locations for {}, {}.", src, e.getMessage());
-      LOG.info("Cannot get locations for {}, {}.", src, e.getMessage());
-      return new ArrayList<>();
-    }, RouterResolveException.class);
+      asyncComplete(new ArrayList<>());
+    }
+
     return asyncReturn(List.class);
   }
 

hadoop-hdfs-project/hadoop-hdfs-rbf/src/test/java/org/apache/hadoop/hdfs/server/federation/router/async/TestRouterAsyncMountTable.java

@@ -20,7 +20,6 @@ package org.apache.hadoop.hdfs.server.federation.router.async;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.hdfs.protocol.ClientProtocol;
 import org.apache.hadoop.hdfs.server.federation.MiniRouterDFSCluster;
 import org.apache.hadoop.hdfs.server.federation.RouterConfigBuilder;
 import org.apache.hadoop.hdfs.server.federation.StateStoreDFSCluster;
@@ -35,7 +34,7 @@ import org.apache.hadoop.hdfs.server.federation.store.protocol.GetMountTableEntr
 import org.apache.hadoop.hdfs.server.federation.store.protocol.GetMountTableEntriesResponse;
 import org.apache.hadoop.hdfs.server.federation.store.protocol.RemoveMountTableEntryRequest;
 import org.apache.hadoop.hdfs.server.federation.store.records.MountTable;
-import org.apache.hadoop.util.Time;
+import org.apache.hadoop.test.LambdaTestUtils;
 import org.junit.After;
 import org.junit.AfterClass;
 import org.junit.BeforeClass;
@@ -43,6 +42,7 @@ import org.junit.Test;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.util.Collections;
 
@@ -56,8 +56,6 @@ public class TestRouterAsyncMountTable {
   public static final Logger LOG = LoggerFactory.getLogger(TestRouterAsyncMountTable.class);
 
   private static StateStoreDFSCluster cluster;
-  private static MiniRouterDFSCluster.NamenodeContext nnContext0;
-  private static MiniRouterDFSCluster.NamenodeContext nnContext1;
   private static MiniRouterDFSCluster.RouterContext routerContext;
   private static MountTableResolver mountTable;
   private static FileSystem routerFs;
@@ -78,9 +76,6 @@ public class TestRouterAsyncMountTable {
     cluster.startRouters();
     cluster.waitClusterUp();
 
-    // Get the end points.
-    nnContext0 = cluster.getNamenode("ns0", null);
-    nnContext1 = cluster.getNamenode("ns1", null);
     routerContext = cluster.getRandomRouter();
     routerFs = routerContext.getFileSystem();
     Router router = routerContext.getRouter();
@@ -134,7 +129,6 @@ public class TestRouterAsyncMountTable {
 
   @Test
   public void testGetEnclosingRoot() throws Exception {
-
     // Add a read only entry.
     MountTable readOnlyEntry = MountTable.newInstance(
         "/readonly", Collections.singletonMap("ns0", "/testdir"));
@@ -155,4 +149,13 @@ public class TestRouterAsyncMountTable {
     // Path does not need to exist.
     assertEquals(routerFs.getEnclosingRoot(new Path("/regular/pathDNE")), new Path("/regular"));
   }
+
+  @Test
+  public void testListNonExistPath() throws Exception {
+    mountTable.setDefaultNSEnable(false);
+    LambdaTestUtils.intercept(FileNotFoundException.class,
+        "File /base does not exist.",
+        "Expect FileNotFoundException.",
+        () -> routerFs.listStatus(new Path("/base")));
+  }
 }