Null path prefix handling (#6101)

Signed-off-by: Santhosh Gandhe <[email protected]>

Author: san81

data-prepper-plugins/s3-sink/src/main/java/org/opensearch/dataprepper/plugins/sink/s3/KeyGenerator.java

@@ -35,7 +35,8 @@ public KeyGenerator(final S3SinkConfig s3SinkConfig,
      */
     public String generateKeyForEvent(final Event event) {
         final String pathPrefix = s3BucketSelector != null ? s3BucketSelector.getPathPrefix() : ObjectKey.buildingPathPrefix(s3SinkConfig, event, expressionEvaluator);
+        final String safePathPrefix = pathPrefix != null ? pathPrefix : "";
         final String namePattern = ObjectKey.objectFileName(s3SinkConfig, extensionProvider.getExtension(), event, expressionEvaluator);
-        return (!pathPrefix.isEmpty()) ? pathPrefix + namePattern : namePattern;
+        return (!safePathPrefix.isEmpty()) ? safePathPrefix + namePattern : namePattern;
     }
 }

data-prepper-plugins/s3-sink/src/main/java/org/opensearch/dataprepper/plugins/sink/s3/accumulator/ObjectKey.java

@@ -5,15 +5,15 @@
 
 package org.opensearch.dataprepper.plugins.sink.s3.accumulator;
 
-import java.util.regex.Pattern;
-
 import org.opensearch.dataprepper.expression.ExpressionEvaluator;
 import org.opensearch.dataprepper.model.event.Event;
 import org.opensearch.dataprepper.plugins.s3keyindex.S3ObjectIndexUtility;
 import org.opensearch.dataprepper.plugins.sink.s3.S3SinkConfig;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.util.regex.Pattern;
+
 /**
  * Building the path prefix and name pattern.
  *
@@ -49,6 +49,9 @@ private static String buildingPathPrefixInternal(final S3SinkConfig s3SinkConfig
                                                      final Event event,
                                                      final ExpressionEvaluator expressionEvaluator) {
         String pathPrefix = s3SinkConfig.getObjectKeyOptions().getPathPrefix();
+        if (pathPrefix == null) {
+            return "";
+        }
         String pathPrefixExpressionResult = expressionEvaluator != null ? event.formatString(pathPrefix, expressionEvaluator, REPLACEMENT_FOR_NON_EXISTENT_KEYS) : pathPrefix;
         StringBuilder s3ObjectPath = new StringBuilder();
         if (pathPrefixExpressionResult != null && !pathPrefixExpressionResult.isEmpty()) {

data-prepper-plugins/s3-sink/src/test/java/org/opensearch/dataprepper/plugins/sink/s3/KeyGeneratorTest.java

@@ -9,6 +9,8 @@
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.NullAndEmptySource;
 import org.mockito.Mock;
 import org.mockito.MockedStatic;
 import org.mockito.junit.jupiter.MockitoExtension;
@@ -149,4 +151,26 @@ void generateKey_with_extension_with_bucketSelector() {
         }
 
     }
+
+    @ParameterizedTest
+    @NullAndEmptySource
+    void test_generateKey_with_null_or_empty_pathPrefix_from_bucketSelector(String pathPrefix) {
+        final String objectName = UUID.randomUUID().toString();
+        when(extensionProvider.getExtension()).thenReturn(null);
+
+        S3BucketSelector s3BucketSelector = mock(S3BucketSelector.class);
+        when(s3BucketSelector.getPathPrefix()).thenReturn(pathPrefix);
+        final KeyGenerator objectUnderTest = createObjectUnderTest(s3BucketSelector);
+
+        final Event event = mock(Event.class);
+
+        try (final MockedStatic<ObjectKey> objectKeyMockedStatic = mockStatic(ObjectKey.class)) {
+            objectKeyMockedStatic.when(() -> ObjectKey.objectFileName(s3SinkConfig, null, event, expressionEvaluator))
+                    .thenReturn(objectName);
+
+            String key = objectUnderTest.generateKeyForEvent(event);
+            assertThat(key, notNullValue());
+            assertThat(key, equalTo(objectName));
+        }
+    }
 }

data-prepper-plugins/s3-sink/src/test/java/org/opensearch/dataprepper/plugins/sink/s3/accumulator/ObjectKeyTest.java

@@ -9,10 +9,13 @@
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.NullAndEmptySource;
 import org.mockito.Mock;
 import org.mockito.junit.jupiter.MockitoExtension;
 import org.opensearch.dataprepper.expression.ExpressionEvaluator;
 import org.opensearch.dataprepper.model.event.Event;
+import org.opensearch.dataprepper.model.event.JacksonEvent;
 import org.opensearch.dataprepper.plugins.sink.s3.S3SinkConfig;
 import org.opensearch.dataprepper.plugins.sink.s3.configuration.ObjectKeyOptions;
 
@@ -36,7 +39,7 @@ class ObjectKeyTest {
     private Event event;
 
     @BeforeEach
-    void setUp() throws Exception {
+    void setUp() {
         when(s3SinkConfig.getObjectKeyOptions()).thenReturn(objectKeyOptions);
     }
 
@@ -85,4 +88,19 @@ void test_objectFileName_default_fileExtension() {
         Assertions.assertNotNull(objectFileName);
         Assertions.assertTrue(objectFileName.contains(".json"));
     }
+
+    @ParameterizedTest
+    @NullAndEmptySource
+    void test_buildingPathPrefix_with_null_formatString_result(final String pathPrefix) {
+        when(objectKeyOptions.getPathPrefix()).thenReturn(pathPrefix);
+        Event event = JacksonEvent.builder()
+                .withData("{}")
+                .withEventType("event")
+                .build();
+        Assertions.assertDoesNotThrow(() -> {
+            String pathPrefixResult = ObjectKey.buildingPathPrefix(s3SinkConfig, event, expressionEvaluator);
+            Assertions.assertEquals("", pathPrefixResult);
+        });
+    }
+
 }