[HUDI-3879] Suppress exceptions that are not fatal in HoodieMetadataT…

…ableValidator (apache#5344)

Co-authored-by: yuezhang <yuezhang@freewheel.tv>
Co-authored-by: Y Ethan Guo <ethan.guoyihua@gmail.com>

hudi-utilities/src/main/java/org/apache/hudi/utilities/HoodieMetadataTableValidator.java

@@ -52,6 +52,7 @@
 import org.apache.hudi.exception.HoodieException;
 import org.apache.hudi.exception.HoodieIOException;
 import org.apache.hudi.exception.HoodieValidationException;
+import org.apache.hudi.exception.TableNotFoundException;
 import org.apache.hudi.io.storage.HoodieFileReader;
 import org.apache.hudi.io.storage.HoodieFileReaderFactory;
 import org.apache.hudi.metadata.HoodieTableMetadata;
@@ -399,7 +400,9 @@ public void doMetadataTableValidation() {
     Set<String> baseFilesForCleaning = Collections.emptySet();
 
     // check metadata table is available to read.
-    checkMetadataTableIsAvailable();
+    if (!checkMetadataTableIsAvailable()) {
+      return;
+    }
 
     if (cfg.skipDataFilesForCleaning) {
       HoodieTimeline inflightCleaningTimeline = metaClient.getActiveTimeline().getCleanerTimeline().filterInflights();
@@ -428,6 +431,12 @@ public void doMetadataTableValidation() {
 
     HoodieSparkEngineContext engineContext = new HoodieSparkEngineContext(jsc);
     List<String> allPartitions = validatePartitions(engineContext, basePath);
+
+    if (allPartitions.isEmpty()) {
+      LOG.warn("The result of getting all partitions is null or empty, skip current validation.");
+      return;
+    }
+
     HoodieMetadataValidationContext metadataTableBasedContext =
         new HoodieMetadataValidationContext(engineContext, cfg, metaClient, true);
     HoodieMetadataValidationContext fsBasedContext =
@@ -465,18 +474,29 @@ public void doMetadataTableValidation() {
    * Check metadata is initialized and available to ready.
    * If not we will log.warn and skip current validation.
    */
-  private void checkMetadataTableIsAvailable() {
+  private boolean checkMetadataTableIsAvailable() {
     try {
       HoodieTableMetaClient mdtMetaClient = HoodieTableMetaClient.builder()
           .setConf(jsc.hadoopConfiguration()).setBasePath(new Path(cfg.basePath, HoodieTableMetaClient.METADATA_TABLE_FOLDER_PATH).toString())
           .setLoadActiveTimelineOnLoad(true)
           .build();
       int finishedInstants = mdtMetaClient.getActiveTimeline().filterCompletedInstants().countInstants();
       if (finishedInstants == 0) {
-        throw new HoodieValidationException("There is no completed instant for metadata table.");
+        if (metaClient.getActiveTimeline().filterCompletedInstants().countInstants() == 0) {
+          LOG.info("There is no completed instant both in metadata table and corresponding data table.");
+          return false;
+        } else {
+          throw new HoodieValidationException("There is no completed instant for metadata table.");
+        }
       }
+      return true;
+    } catch (TableNotFoundException tbe) {
+      // Suppress the TableNotFound exception if Metadata table is not available to read for now
+      LOG.warn("Metadata table is not found. Skip current validation.");
+      return false;
     } catch (Exception ex) {
-      LOG.warn("Metadata table is not available to ready for now, ", ex);
+      LOG.warn("Metadata table is not available to read for now, ", ex);
+      return false;
     }
   }