user should be able to pass custom mcp kafka topic

metadata-integration/java/acryl-spark-lineage/src/main/java/datahub/spark/DatahubEventEmitter.java

@@ -82,7 +82,10 @@ private Optional<Emitter> getEmitter() {
             (KafkaDatahubEmitterConfig) datahubConf.getDatahubEmitterConfig();
         try {
           emitter =
-              Optional.of(new KafkaEmitter(datahubKafkaEmitterConfig.getKafkaEmitterConfig()));
+              Optional.of(
+                  new KafkaEmitter(
+                      datahubKafkaEmitterConfig.getKafkaEmitterConfig(),
+                      datahubKafkaEmitterConfig.getMcpTopic()));
         } catch (IOException e) {
           throw new RuntimeException(e);
         }

metadata-integration/java/acryl-spark-lineage/src/main/java/datahub/spark/DatahubSparkListener.java

@@ -188,8 +188,12 @@ public Optional<DatahubEmitterConfig> initializeEmitter(Config sparkConf) {
                   });
           kafkaEmitterConfig.producerConfig(kafkaConfig);
         }
-
-        return Optional.of(new KafkaDatahubEmitterConfig(kafkaEmitterConfig.build()));
+        if (sparkConf.hasPath(SparkConfigParser.KAFKA_MCP_TOPIC)) {
+          String mcpTopic = sparkConf.getString(SparkConfigParser.KAFKA_MCP_TOPIC);
+          return Optional.of(new KafkaDatahubEmitterConfig(kafkaEmitterConfig.build(), mcpTopic));
+        } else {
+          return Optional.of(new KafkaDatahubEmitterConfig(kafkaEmitterConfig.build()));
+        }
       case "file":
         log.info("File Emitter Configuration: File emitter will be used");
         FileEmitterConfig.FileEmitterConfigBuilder fileEmitterConfig = FileEmitterConfig.builder();

metadata-integration/java/acryl-spark-lineage/src/main/java/datahub/spark/conf/KafkaDatahubEmitterConfig.java

@@ -1,5 +1,6 @@
 package datahub.spark.conf;
 
+import datahub.client.kafka.KafkaEmitter;
 import datahub.client.kafka.KafkaEmitterConfig;
 import lombok.Getter;
 import lombok.Setter;
@@ -11,8 +12,15 @@
 public class KafkaDatahubEmitterConfig implements DatahubEmitterConfig {
   final String type = "kafka";
   KafkaEmitterConfig kafkaEmitterConfig;
+  String mcpTopic;
 
   public KafkaDatahubEmitterConfig(KafkaEmitterConfig kafkaEmitterConfig) {
     this.kafkaEmitterConfig = kafkaEmitterConfig;
+    this.mcpTopic = KafkaEmitter.DEFAULT_MCP_KAFKA_TOPIC;
+  }
+
+  public KafkaDatahubEmitterConfig(KafkaEmitterConfig kafkaEmitterConfig, String mcpTopic) {
+    this.kafkaEmitterConfig = kafkaEmitterConfig;
+    this.mcpTopic = mcpTopic;
   }
 }

metadata-integration/java/acryl-spark-lineage/src/main/java/datahub/spark/conf/SparkConfigParser.java

@@ -32,6 +32,7 @@ public class SparkConfigParser {
   public static final String DISABLE_SSL_VERIFICATION_KEY = "rest.disable_ssl_verification";
   public static final String MAX_RETRIES = "rest.max_retries";
   public static final String RETRY_INTERVAL_IN_SEC = "rest.retry_interval_in_sec";
+  public static final String KAFKA_MCP_TOPIC = "kafka.mcp_topic";
   public static final String KAFKA_EMITTER_BOOTSTRAP = "kafka.bootstrap";
   public static final String KAFKA_EMITTER_SCHEMA_REGISTRY_URL = "kafka.schema_registry_url";
   public static final String KAFKA_EMITTER_SCHEMA_REGISTRY_CONFIG = "kafka.schema_registry_config";

metadata-integration/java/datahub-client/src/main/java/datahub/client/kafka/AvroSerializer.java

@@ -9,7 +9,7 @@
 import org.apache.avro.generic.GenericData;
 import org.apache.avro.generic.GenericRecord;
 
-class AvroSerializer {
+public class AvroSerializer {
 
   private final Schema _recordSchema;
   private final Schema _genericAspectSchema;

metadata-integration/java/datahub-client/src/main/java/datahub/client/kafka/KafkaEmitter.java

@@ -31,14 +31,25 @@ public class KafkaEmitter implements Emitter {
   private final Properties kafkaConfigProperties;
   private AvroSerializer _avroSerializer;
   private static final int ADMIN_CLIENT_TIMEOUT_MS = 5000;
+  private final String mcpKafkaTopic;
 
   /**
    * The default constructor
    *
-   * @param config
-   * @throws IOException
+   * @param config KafkaEmitterConfig
+   * @throws IOException when Avro Serialization fails
    */
   public KafkaEmitter(KafkaEmitterConfig config) throws IOException {
+    this(config, DEFAULT_MCP_KAFKA_TOPIC);
+  }
+
+  /**
+   * Constructor that takes in KafkaEmitterConfig and mcp Kafka Topic Name
+   *
+   * @param config KafkaEmitterConfig
+   * @throws IOException when Avro Serialization fails
+   */
+  public KafkaEmitter(KafkaEmitterConfig config, String mcpKafkaTopic) throws IOException {
     this.config = config;
     kafkaConfigProperties = new Properties();
     kafkaConfigProperties.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, this.config.getBootstrap());
@@ -54,6 +65,7 @@ public KafkaEmitter(KafkaEmitterConfig config) throws IOException {
 
     producer = new KafkaProducer<>(kafkaConfigProperties);
     _avroSerializer = new AvroSerializer();
+    this.mcpKafkaTopic = mcpKafkaTopic;
   }
 
   @Override
@@ -73,8 +85,7 @@ public Future<MetadataWriteResponse> emit(MetadataChangeProposal mcp, Callback d
       throws IOException {
     GenericRecord genricRecord = _avroSerializer.serialize(mcp);
     ProducerRecord<Object, Object> record =
-        new ProducerRecord<>(
-            KafkaEmitter.DEFAULT_MCP_KAFKA_TOPIC, mcp.getEntityUrn().toString(), genricRecord);
+        new ProducerRecord<>(this.mcpKafkaTopic, mcp.getEntityUrn().toString(), genricRecord);
     org.apache.kafka.clients.producer.Callback callback =
         new org.apache.kafka.clients.producer.Callback() {