[HUDI-3015] Implement #reset and #sync for metadata filesystem view (#4307)

hudi-common/src/main/java/org/apache/hudi/common/table/view/AbstractTableFileSystemView.java

@@ -257,7 +257,7 @@ public abstract class AbstractTableFileSystemView implements SyncableFileSystemV
    * Clears the partition Map and reset view states.
    */
   @Override
-  public final void reset() {
+  public void reset() {
     try {
       writeLock.lock();
       clear();
@@ -1135,8 +1135,7 @@ public abstract class AbstractTableFileSystemView implements SyncableFileSystemV
    */
   protected void runSync(HoodieTimeline oldTimeline, HoodieTimeline newTimeline) {
     refreshTimeline(newTimeline);
-    addedPartitions.clear();
-    resetViewState();
+    clear();
     // Initialize with new Hoodie timeline.
     init(metaClient, newTimeline);
   }

hudi-common/src/main/java/org/apache/hudi/common/table/view/PriorityBasedFileSystemView.java

@@ -253,8 +253,8 @@ public class PriorityBasedFileSystemView implements SyncableFileSystemView, Seri
 
   @Override
   public void sync() {
-    preferredView.reset();
-    secondaryView.reset();
+    preferredView.sync();
+    secondaryView.sync();
   }
 
   @Override

hudi-common/src/main/java/org/apache/hudi/common/table/view/RemoteHoodieTableFileSystemView.java

@@ -413,6 +413,8 @@ public class RemoteHoodieTableFileSystemView implements SyncableFileSystemView,
   public boolean refresh() {
     Map<String, String> paramsMap = getParams();
     try {
+      // refresh the local timeline first.
+      this.timeline = metaClient.reloadActiveTimeline().filterCompletedAndCompactionInstants();
       return executeRequest(REFRESH_TABLE, paramsMap, new TypeReference<Boolean>() {}, RequestMethod.POST);
     } catch (IOException e) {
       throw new HoodieRemoteException(e);
@@ -450,7 +452,6 @@ public class RemoteHoodieTableFileSystemView implements SyncableFileSystemView,
 
   @Override
   public void reset() {
-    timeline = metaClient.reloadActiveTimeline().filterCompletedAndCompactionInstants();
     refresh();
   }
 

hudi-common/src/main/java/org/apache/hudi/metadata/FileSystemBackedTableMetadata.java

@@ -139,4 +139,9 @@ public class FileSystemBackedTableMetadata implements HoodieTableMetadata {
   public void close() throws Exception {
     // no-op
   }
+
+  @Override
+  public void reset() {
+    // no-op
+  }
 }

hudi-common/src/main/java/org/apache/hudi/metadata/HoodieBackedTableMetadata.java

@@ -441,4 +441,10 @@ public class HoodieBackedTableMetadata extends BaseTableMetadata {
     }
     return Option.empty();
   }
+
+  @Override
+  public void reset() {
+    initIfNeeded();
+    dataMetaClient.reloadActiveTimeline();
+  }
 }

hudi-common/src/main/java/org/apache/hudi/metadata/HoodieMetadataFileSystemView.java

@@ -65,6 +65,18 @@ public class HoodieMetadataFileSystemView extends HoodieTableFileSystemView {
     return tableMetadata.getAllFilesInPartition(partitionPath);
   }
 
+  @Override
+  public void reset() {
+    super.reset();
+    tableMetadata.reset();
+  }
+
+  @Override
+  public void sync() {
+    super.sync();
+    tableMetadata.reset();
+  }
+
   @Override
   public void close() {
     try {

hudi-common/src/main/java/org/apache/hudi/metadata/HoodieTableMetadata.java

@@ -113,4 +113,9 @@ public interface HoodieTableMetadata extends Serializable, AutoCloseable {
    * Returns the timestamp of the latest compaction.
    */
   Option<String> getLatestCompactionTime();
+
+  /**
+   * Clear the states of the table metadata.
+   */
+  void reset();
 }

hudi-common/src/test/java/org/apache/hudi/common/table/view/TestPriorityBasedFileSystemView.java

@@ -622,8 +622,8 @@ public class TestPriorityBasedFileSystemView {
   @Test
   public void testSync() {
     fsView.sync();
-    verify(primary, times(1)).reset();
-    verify(secondary, times(1)).reset();
+    verify(primary, times(1)).sync();
+    verify(secondary, times(1)).sync();
   }
 
   @Test