Deserializes the byte[] messages as a JSON object and reads
+ * the specified fields.
+ *
+ *
Failure during deserialization are forwarded as wrapped IOExceptions.
+ */
+public class JsonRowDeserializationSchema implements DeserializationSchema By default, a missing field is ignored and the field is set to null.
+ *
+ * @param failOnMissingField Flag indicating whether to fail or not on a missing field.
+ */
+ public void setFailOnMissingField(boolean failOnMissingField) {
+ this.failOnMissingField = failOnMissingField;
+ }
+
+}
diff --git a/flink-streaming-connectors/flink-connector-kafka-base/src/test/java/org/apache/flink/streaming/connectors/kafka/JsonRowDeserializationSchemaTest.java b/flink-streaming-connectors/flink-connector-kafka-base/src/test/java/org/apache/flink/streaming/connectors/kafka/JsonRowDeserializationSchemaTest.java
new file mode 100644
index 0000000000000000000000000000000000000000..68225e2ae461fbad7e660121ac4b24855b9e0047
--- /dev/null
+++ b/flink-streaming-connectors/flink-connector-kafka-base/src/test/java/org/apache/flink/streaming/connectors/kafka/JsonRowDeserializationSchemaTest.java
@@ -0,0 +1,124 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.flink.streaming.connectors.kafka;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.apache.flink.api.table.Row;
+import org.apache.flink.streaming.util.serialization.JsonRowDeserializationSchema;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.util.concurrent.ThreadLocalRandom;
+
+import static org.junit.Assert.assertArrayEquals;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
+public class JsonRowDeserializationSchemaTest {
+
+ /**
+ * Tests simple deserialization.
+ */
+ @Test
+ public void testDeserialization() throws Exception {
+ long id = 1238123899121L;
+ String name = "asdlkjasjkdla998y1122";
+ byte[] bytes = new byte[1024];
+ ThreadLocalRandom.current().nextBytes(bytes);
+
+ ObjectMapper objectMapper = new ObjectMapper();
+
+ // Root
+ ObjectNode root = objectMapper.createObjectNode();
+ root.put("id", id);
+ root.put("name", name);
+ root.put("bytes", bytes);
+
+ byte[] serializedJson = objectMapper.writeValueAsBytes(root);
+
+ JsonRowDeserializationSchema deserializationSchema = new JsonRowDeserializationSchema(
+ new String[] { "id", "name", "bytes" },
+ new Class[] { Long.class, String.class, byte[].class });
+
+ Row deserialized = deserializationSchema.deserialize(serializedJson);
+
+ assertEquals(3, deserialized.productArity());
+ assertEquals(id, deserialized.productElement(0));
+ assertEquals(name, deserialized.productElement(1));
+ assertArrayEquals(bytes, (byte[]) deserialized.productElement(2));
+ }
+
+ /**
+ * Tests deserialization with non-existing field name.
+ */
+ @Test
+ public void testMissingNode() throws Exception {
+ ObjectMapper objectMapper = new ObjectMapper();
+
+ // Root
+ ObjectNode root = objectMapper.createObjectNode();
+ root.put("id", 123123123);
+ byte[] serializedJson = objectMapper.writeValueAsBytes(root);
+
+ JsonRowDeserializationSchema deserializationSchema = new JsonRowDeserializationSchema(
+ new String[] { "name" },
+ new Class[] { String.class });
+
+ Row row = deserializationSchema.deserialize(serializedJson);
+
+ assertEquals(1, row.productArity());
+ assertNull("Missing field not null", row.productElement(0));
+
+ deserializationSchema.setFailOnMissingField(true);
+
+ try {
+ deserializationSchema.deserialize(serializedJson);
+ fail("Did not throw expected Exception");
+ } catch (IOException e) {
+ assertTrue(e.getCause() instanceof IllegalStateException);
+ }
+ }
+
+ /**
+ * Tests that number of field names and types has to match.
+ */
+ @Test
+ public void testNumberOfFieldNamesAndTypesMismatch() throws Exception {
+ try {
+ new JsonRowDeserializationSchema(
+ new String[] { "one", "two", "three" },
+ new Class[] { Long.class });
+ fail("Did not throw expected Exception");
+ } catch (IllegalArgumentException ignored) {
+ // Expected
+ }
+
+ try {
+ new JsonRowDeserializationSchema(
+ new String[] { "one" },
+ new Class[] { Long.class, String.class });
+ fail("Did not throw expected Exception");
+ } catch (IllegalArgumentException ignored) {
+ // Expected
+ }
+ }
+}