HDDS-1863. Freon RandomKeyGenerator even if keySize is set to 0, it returns some random data to key. (#1167)

hadoop-ozone/tools/src/main/java/org/apache/hadoop/ozone/freon/RandomKeyGenerator.java

@@ -26,7 +26,6 @@ import java.text.SimpleDateFormat;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.Map;
-import java.util.UUID;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.Callable;
 import java.util.concurrent.ConcurrentHashMap;
@@ -263,9 +262,7 @@ public final class RandomKeyGenerator implements Callable<Void> {
     // Compute the common initial digest for all keys without their UUID
     if (validateWrites) {
       commonInitialMD = DigestUtils.getDigest(DIGEST_ALGORITHM);
-      int uuidLength = UUID.randomUUID().toString().length();
-      keySize = Math.max(uuidLength, keySize);
-      for (long nrRemaining = keySize - uuidLength; nrRemaining > 0;
+      for (long nrRemaining = keySize; nrRemaining > 0;
           nrRemaining -= bufferSize) {
         int curSize = (int)Math.min(bufferSize, nrRemaining);
         commonInitialMD.update(keyValueBuffer, 0, curSize);
@@ -682,7 +679,6 @@ public final class RandomKeyGenerator implements Callable<Void> {
         + RandomStringUtils.randomNumeric(5);
     LOG.trace("Adding key: {} in bucket: {} of volume: {}",
         keyName, bucketName, volumeName);
-    byte[] randomValue = DFSUtil.string2Bytes(UUID.randomUUID().toString());
     try {
       try (Scope scope = GlobalTracer.get().buildSpan("createKey")
           .startActive(true)) {
@@ -697,12 +693,11 @@ public final class RandomKeyGenerator implements Callable<Void> {
         try (Scope writeScope = GlobalTracer.get().buildSpan("writeKeyData")
             .startActive(true)) {
           long keyWriteStart = System.nanoTime();
-          for (long nrRemaining = keySize - randomValue.length;
+          for (long nrRemaining = keySize;
                nrRemaining > 0; nrRemaining -= bufferSize) {
             int curSize = (int) Math.min(bufferSize, nrRemaining);
             os.write(keyValueBuffer, 0, curSize);
           }
-          os.write(randomValue);
           os.close();
 
           long keyWriteDuration = System.nanoTime() - keyWriteStart;
@@ -716,7 +711,6 @@ public final class RandomKeyGenerator implements Callable<Void> {
 
       if (validateWrites) {
         MessageDigest tmpMD = (MessageDigest) commonInitialMD.clone();
-        tmpMD.update(randomValue);
         boolean validate = validationQueue.offer(
             new KeyValidate(bucket, keyName, tmpMD.digest()));
         if (validate) {

hadoop-ozone/tools/src/test/java/org/apache/hadoop/ozone/freon/TestRandomKeyGenerator.java

@@ -128,6 +128,25 @@ public class TestRandomKeyGenerator {
     Assert.assertEquals(1, randomKeyGenerator.getSuccessfulValidationCount());
   }
 
+  @Test
+  public void fileWithSizeZero() throws Exception {
+    RandomKeyGenerator randomKeyGenerator =
+        new RandomKeyGenerator((OzoneConfiguration) cluster.getConf());
+    randomKeyGenerator.setNumOfVolumes(1);
+    randomKeyGenerator.setNumOfBuckets(1);
+    randomKeyGenerator.setNumOfKeys(1);
+    randomKeyGenerator.setNumOfThreads(1);
+    randomKeyGenerator.setKeySize(0);
+    randomKeyGenerator.setFactor(ReplicationFactor.THREE);
+    randomKeyGenerator.setType(ReplicationType.RATIS);
+    randomKeyGenerator.setValidateWrites(true);
+    randomKeyGenerator.call();
+    Assert.assertEquals(1, randomKeyGenerator.getNumberOfVolumesCreated());
+    Assert.assertEquals(1, randomKeyGenerator.getNumberOfBucketsCreated());
+    Assert.assertEquals(1, randomKeyGenerator.getNumberOfKeysAdded());
+    Assert.assertEquals(1, randomKeyGenerator.getSuccessfulValidationCount());
+  }
+
   @Test
   public void testThreadPoolSize() throws Exception {
     RandomKeyGenerator randomKeyGenerator =