HDDS-13943. Improve error message for malformed input in DirstreamClientHandler

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/stream/DirstreamClientHandler.java

@@ -80,6 +80,10 @@ public void doRead(ChannelHandlerContext ctx, ByteBuf buffer)
         name.release();
         buffer.skipBytes(1);
         String[] parts = currentFileName.split(" ", 2);
+        if (parts.length < 2 || parts[1] == null || parts[1].isEmpty()) {
+          throw new IllegalArgumentException("Invalid file name format: " + currentFileName
+              + ". Expected format: SIZE FILENAME");
+        }
         remaining = Long.parseLong(parts[0]);
         Path destFilePath = destination.mapToDestination(parts[1]);
         final Path destfileParent = destFilePath.getParent();

hadoop-hdds/container-service/src/test/java/org/apache/hadoop/ozone/container/stream/TestDirstreamClientHandler.java

@@ -18,6 +18,7 @@
 package org.apache.hadoop.ozone.container.stream;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
 import io.netty.buffer.ByteBuf;
@@ -113,6 +114,39 @@ public void splitContent() throws IOException {
     assertEquals("yyy", getContent("bsd.txt"));
   }
 
+  @Test
+  public void testInvalidFormatMissingSpace() {
+    final DirstreamClientHandler handler = new DirstreamClientHandler(
+        new DirectoryServerDestination(tmpDir));
+
+    IllegalArgumentException exception = assertThrows(IllegalArgumentException.class, () -> {
+      handler.doRead(null, wrap("123\n"));
+    });
+    assertTrue(exception.getMessage().contains("Invalid file name format"));
+  }
+
+  @Test
+  public void testInvalidFormatEmptyFileName() {
+    final DirstreamClientHandler handler = new DirstreamClientHandler(
+        new DirectoryServerDestination(tmpDir));
+
+    IllegalArgumentException exception = assertThrows(IllegalArgumentException.class, () -> {
+      handler.doRead(null, wrap("123 \n"));
+    });
+    assertTrue(exception.getMessage().contains("Invalid file name format"));
+  }
+
+  @Test
+  public void testInvalidFormatOnlySize() {
+    final DirstreamClientHandler handler = new DirstreamClientHandler(
+        new DirectoryServerDestination(tmpDir));
+
+    IllegalArgumentException exception = assertThrows(IllegalArgumentException.class, () -> {
+      handler.doRead(null, wrap("12345\n"));
+    });
+    assertTrue(exception.getMessage().contains("Invalid file name format"));
+  }
+
   @Nonnull
   private String getContent(String name) throws IOException {
     return new String(Files.readAllBytes(tmpDir.resolve(name)),