HDFS-14661. RBF: updateMountTableEntry shouldn't update mountTableEntry if targetPath not exist. Contributed by xuzq.

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

@@ -269,12 +269,18 @@ public class RouterAdminServer extends AbstractService
       UpdateMountTableEntryRequest request) throws IOException {
     UpdateMountTableEntryResponse response =
         getMountTableStore().updateMountTableEntry(request);
-
-    MountTable mountTable = request.getEntry();
-    if (mountTable != null && router.isQuotaEnabled()) {
-      synchronizeQuota(mountTable.getSourcePath(),
-          mountTable.getQuota().getQuota(),
-          mountTable.getQuota().getSpaceQuota());
+    try {
+      MountTable mountTable = request.getEntry();
+      if (mountTable != null && router.isQuotaEnabled()) {
+        synchronizeQuota(mountTable.getSourcePath(),
+            mountTable.getQuota().getQuota(),
+            mountTable.getQuota().getSpaceQuota());
+      }
+    } catch (Exception e) {
+      // Ignore exception, if any while reseting quota. Specifically to handle
+      // if the actual destination doesn't exist.
+      LOG.warn("Unable to reset quota at the destinations for {}: {}",
+          request.getEntry().toString(), e.getMessage());
     }
     return response;
   }

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

@@ -59,6 +59,7 @@ import org.apache.hadoop.hdfs.server.federation.store.protocol.GetMountTableEntr
 import org.apache.hadoop.hdfs.server.federation.store.protocol.RemoveMountTableEntryRequest;
 import org.apache.hadoop.hdfs.server.federation.store.protocol.RemoveMountTableEntryResponse;
 import org.apache.hadoop.hdfs.server.federation.store.protocol.UpdateMountTableEntryRequest;
+import org.apache.hadoop.hdfs.server.federation.store.protocol.UpdateMountTableEntryResponse;
 import org.apache.hadoop.hdfs.server.federation.store.records.MountTable;
 import org.apache.hadoop.test.GenericTestUtils;
 import org.apache.hadoop.util.Time;
@@ -244,6 +245,25 @@ public class TestRouterQuota {
     return addResponse.getStatus();
   }
 
+  /**
+   * Update a mount table entry to the mount table through the admin API.
+   * @param entry Mount table entry to update.
+   * @return If it was successfully updated
+   * @throws IOException Problems update entries
+   */
+  private boolean updateMountTable(final MountTable entry) throws IOException {
+    RouterClient client = routerContext.getAdminClient();
+    MountTableManager mountTableManager = client.getMountTableManager();
+    UpdateMountTableEntryRequest updateRequest =
+        UpdateMountTableEntryRequest.newInstance(entry);
+    UpdateMountTableEntryResponse updateResponse =
+        mountTableManager.updateMountTableEntry(updateRequest);
+
+    // Reload the Router cache
+    resolver.loadCache(true);
+    return updateResponse.getStatus();
+  }
+
   /**
    * Append data in specified file.
    * @param path Path of file.
@@ -496,11 +516,7 @@ public class TestRouterQuota {
 
     mountTable.setQuota(new RouterQuotaUsage.Builder().quota(updateNsQuota)
         .spaceQuota(updateSsQuota).build());
-    UpdateMountTableEntryRequest updateRequest = UpdateMountTableEntryRequest
-        .newInstance(mountTable);
-    RouterClient client = routerContext.getAdminClient();
-    MountTableManager mountTableManager = client.getMountTableManager();
-    mountTableManager.updateMountTableEntry(updateRequest);
+    updateMountTable(mountTable);
 
     // verify if the quota is updated in real path
     realQuota = nnContext1.getFileSystem().getQuotaUsage(
@@ -512,18 +528,21 @@ public class TestRouterQuota {
     mountTable.setQuota(new RouterQuotaUsage.Builder()
         .quota(HdfsConstants.QUOTA_RESET)
         .spaceQuota(HdfsConstants.QUOTA_RESET).build());
-
-    updateRequest = UpdateMountTableEntryRequest
-        .newInstance(mountTable);
-    client = routerContext.getAdminClient();
-    mountTableManager = client.getMountTableManager();
-    mountTableManager.updateMountTableEntry(updateRequest);
+    updateMountTable(mountTable);
 
     // verify if the quota is updated in real path
     realQuota = nnContext1.getFileSystem().getQuotaUsage(
         new Path("/testsync"));
     assertEquals(HdfsConstants.QUOTA_RESET, realQuota.getQuota());
     assertEquals(HdfsConstants.QUOTA_RESET, realQuota.getSpaceQuota());
+
+    // Verify updating mount entry with actual destinations not present.
+    mountTable = MountTable.newInstance("/testupdate",
+        Collections.singletonMap("ns0", "/testupdate"), Time.now(), Time.now());
+    addMountTable(mountTable);
+    mountTable.setQuota(new RouterQuotaUsage.Builder().quota(1)
+        .spaceQuota(2).build());
+    assertTrue(updateMountTable(mountTable));
   }
 
   @Test