Fix relational tablet batch redirection and empty tablets

iotdb-client/session/src/main/java/org/apache/iotdb/session/Session.java

diff --git a/iotdb-client/session/src/main/java/org/apache/iotdb/session/Session.java b/iotdb-client/session/src/main/java/org/apache/iotdb/session/Session.java
index 63e11b9..edb6690 100644
--- a/iotdb-client/session/src/main/java/org/apache/iotdb/session/Session.java
+++ b/iotdb-client/session/src/main/java/org/apache/iotdb/session/Session.java
@@ -2874,6 +2874,19 @@
    */
   public void insertRelationalTablets(List<Tablet> tablets)
       throws IoTDBConnectionException, StatementExecutionException {
+    if (tablets.isEmpty()) {
+      throw new BatchExecutionException(SessionMessages.NO_TABLET_INSERTING);
+    }
+    final List<Tablet> nonEmptyTablets = new ArrayList<>(tablets.size());
+    for (final Tablet tablet : tablets) {
+      if (tablet.getRowSize() > 0) {
+        nonEmptyTablets.add(tablet);
+      }
+    }
+    if (nonEmptyTablets.isEmpty()) {
+      return;
+    }
+    tablets = nonEmptyTablets;
     final boolean recordMergeTabletsCost = enableMergeTablets;
     long mergeTabletsCost = 0;
     if (enableMergeTablets) {
@@ -2881,9 +2894,6 @@
       tablets = mergeRelationalTablets(tablets);
       mergeTabletsCost = System.nanoTime() - mergeTabletsStartTime;
     }
-    if (tablets.isEmpty()) {
-      throw new BatchExecutionException(SessionMessages.NO_TABLET_INSERTING);
-    }
     final long insertTabletsStartTime = System.nanoTime();
     if (enableRedirection) {
       insertRelationalTabletsWithLeaderCache(tablets);
@@ -2893,10 +2903,7 @@
       for (Tablet tablet : tablets) {
         request.addToColumnCategoriesList(toEnumOrdinalsAsBytes(tablet.getColumnTypes()));
       }
-      try {
-        getDefaultSessionConnection().insertTablets(request);
-      } catch (RedirectException ignored) {
-      }
+      getDefaultSessionConnection().insertTabletsWithoutRedirect(request);
     }
     if (recordMergeTabletsCost) {
       recordMergeTabletsCost(mergeTabletsCost, System.nanoTime() - insertTabletsStartTime);

iotdb-client/session/src/main/java/org/apache/iotdb/session/SessionConnection.java

diff --git a/iotdb-client/session/src/main/java/org/apache/iotdb/session/SessionConnection.java b/iotdb-client/session/src/main/java/org/apache/iotdb/session/SessionConnection.java
index 4c30ba4..42ded5a 100644
--- a/iotdb-client/session/src/main/java/org/apache/iotdb/session/SessionConnection.java
+++ b/iotdb-client/session/src/main/java/org/apache/iotdb/session/SessionConnection.java
@@ -876,6 +876,11 @@
         () -> insertTabletsInternal(request), () -> devices);
   }
 
+  protected void insertTabletsWithoutRedirect(TSInsertTabletsReq request)
+      throws IoTDBConnectionException, StatementExecutionException {
+    callWithRetryAndVerify(() -> insertTabletsInternal(request));
+  }
+
   private TSStatus insertTabletsInternal(TSInsertTabletsReq request) throws TException {
     request.setSessionId(sessionId);
     return client.insertTablets(request);

iotdb-client/session/src/test/java/org/apache/iotdb/session/SessionConnectionTest.java

diff --git a/iotdb-client/session/src/test/java/org/apache/iotdb/session/SessionConnectionTest.java b/iotdb-client/session/src/test/java/org/apache/iotdb/session/SessionConnectionTest.java
index fea7846..5c3adb8 100644
--- a/iotdb-client/session/src/test/java/org/apache/iotdb/session/SessionConnectionTest.java
+++ b/iotdb-client/session/src/test/java/org/apache/iotdb/session/SessionConnectionTest.java
@@ -352,6 +352,22 @@
   }
 
   @Test
+  public void testInsertTabletsWithoutRedirectIgnoresRowRedirectStatus()
+      throws IoTDBConnectionException, StatementExecutionException, TException {
+    final TSStatus first = new TSStatus(TSStatusCode.REDIRECTION_RECOMMEND.getStatusCode());
+    first.setRedirectNode(new TEndPoint("127.0.0.2", 6667));
+    final TSStatus second = new TSStatus(TSStatusCode.REDIRECTION_RECOMMEND.getStatusCode());
+    second.setRedirectNode(new TEndPoint("127.0.0.3", 6667));
+    final TSStatus status = new TSStatus(TSStatusCode.REDIRECTION_RECOMMEND.getStatusCode());
+    status.setSubStatus(Arrays.asList(first, second));
+    Mockito.when(client.insertTablets(any())).thenReturn(status);
+
+    sessionConnection.insertTabletsWithoutRedirect(new TSInsertTabletsReq());
+
+    Mockito.verify(client).insertTablets(any(TSInsertTabletsReq.class));
+  }
+
+  @Test
   public void testDeleteEmptyTimeseries()
       throws IoTDBConnectionException, StatementExecutionException, TException {
     sessionConnection.deleteTimeseries(Collections.emptyList());

iotdb-client/session/src/test/java/org/apache/iotdb/session/SessionTest.java

diff --git a/iotdb-client/session/src/test/java/org/apache/iotdb/session/SessionTest.java b/iotdb-client/session/src/test/java/org/apache/iotdb/session/SessionTest.java
index ac5959b..05d5f0a 100644
--- a/iotdb-client/session/src/test/java/org/apache/iotdb/session/SessionTest.java
+++ b/iotdb-client/session/src/test/java/org/apache/iotdb/session/SessionTest.java
@@ -1369,6 +1369,57 @@
   }
 
   @Test
+  public void testInsertRelationalTabletsWithRedirectionDisabledIgnoresRedirect() throws Exception {
+    final List<String> measurements = Arrays.asList("tag1", "s1");
+    final Tablet tablet =
+        new Tablet(
+            "table1",
+            measurements,
+            Arrays.asList(TSDataType.STRING, TSDataType.INT64),
+            Arrays.asList(ColumnCategory.TAG, ColumnCategory.FIELD),
+            2);
+    tablet.addTimestamp(0, 1L);
+    tablet.addValue("tag1", 0, "d1");
+    tablet.addValue("s1", 0, 11L);
+    tablet.addTimestamp(1, 2L);
+    tablet.addValue("tag1", 1, "d2");
+    tablet.addValue("s1", 1, 22L);
+    Whitebox.setInternalState(session, "enableRedirection", false);
+
+    ((Session) session).insertRelationalTablets(Collections.singletonList(tablet));
+
+    Mockito.verify(sessionConnection).insertTabletsWithoutRedirect(any(TSInsertTabletsReq.class));
+    Mockito.verify(sessionConnection, Mockito.never()).insertTablets(any(TSInsertTabletsReq.class));
+    Mockito.verify(sessionConnection, Mockito.never())
+        .insertTablets(any(TSInsertTabletsReq.class), anyList());
+  }
+
+  @Test
+  public void testInsertRelationalTabletsIgnoresAllEmptyTablets() throws Exception {
+    final Tablet first =
+        new Tablet(
+            "table1",
+            Arrays.asList("tag1", "s1"),
+            Arrays.asList(TSDataType.STRING, TSDataType.INT64),
+            Arrays.asList(ColumnCategory.TAG, ColumnCategory.FIELD),
+            1);
+    final Tablet second =
+        new Tablet(
+            "table1",
+            Arrays.asList("tag1", "s1"),
+            Arrays.asList(TSDataType.STRING, TSDataType.INT64),
+            Arrays.asList(ColumnCategory.TAG, ColumnCategory.FIELD),
+            1);
+    Whitebox.setInternalState(session, "enableRedirection", true);
+
+    ((Session) session).insertRelationalTablets(Arrays.asList(first, second));
+
+    Mockito.verify(sessionConnection, Mockito.never())
+        .insertTablets(any(TSInsertTabletsReq.class), anyList());
+    Mockito.verify(sessionConnection, Mockito.never()).insertTablets(any(TSInsertTabletsReq.class));
+  }
+
+  @Test
   public void testSplitRelationalTabletAllocatesOncePerEndpoint() throws Exception {
     final int rowCount = 1000;
     final List<String> measurements = Arrays.asList("tag1", "s1");