Doris Kafka Connector

Kafka Connect is a scalable and reliable tool for data transmission between Apache Kafka and other systems. Connectors can be defined Move large amounts of data in and out of Kafka.

The Doris community provides the doris-kafka-connector plug-in, which can write data in the Kafka topic to Doris.

Usage Doris Kafka Connector

Download

doris-kafka-connector

maven dependencies

<dependency>
  <groupId>org.apache.doris</groupId>
  <artifactId>doris-kafka-connector</artifactId>
  <version>1.0.0</version>
</dependency>

Standalone mode startup

Configure connect-standalone.properties

# Modify broker address
bootstrap.servers=127.0.0.1:9092

Configure doris-connector-sink.properties Create doris-connector-sink.properties in the config directory and configure the following content:

name=test-doris-sink
connector.class=org.apache.doris.kafka.connector.DorisSinkConnector
topics=topic_test
doris.topic2table.map=topic_test:test_kafka_tbl
buffer.count.records=10000
buffer.flush.time=120
buffer.size.bytes=5000000
doris.urls=10.10.10.1
doris.http.port=8030
doris.query.port=9030
doris.user=root
doris.password=
doris.database=test_db
key.converter=org.apache.kafka.connect.storage.StringConverter
value.converter=org.apache.kafka.connect.json.JsonConverter

Start Standalone

$KAFKA_HOME/bin/connect-standalone.sh -daemon $KAFKA_HOME/config/connect-standalone.properties $KAFKA_HOME/config/doris-connector-sink.properties

note

Note: It is generally not recommended to use standalone mode in a production environment.

Distributed mode startup

Configure connect-distributed.properties

# Modify broker address
bootstrap.servers=127.0.0.1:9092

# Modify group.id, the same cluster needs to be consistent
group.id=connect-cluster

Start Distributed

$KAFKA_HOME/bin/connect-distributed.sh -daemon $KAFKA_HOME/config/connect-distributed.properties

Add Connector

curl -i http://127.0.0.1:8083/connectors -H "Content-Type: application/json" -X POST -d '{
  "name":"test-doris-sink-cluster",
  "config":{
    "connector.class":"org.apache.doris.kafka.connector.DorisSinkConnector",
    "topics":"topic_test",
    "doris.topic2table.map": "topic_test:test_kafka_tbl",
    "buffer.count.records":"10000",
    "buffer.flush.time":"120",
    "buffer.size.bytes":"5000000",
    "doris.urls":"10.10.10.1",
    "doris.user":"root",
    "doris.password":"",
    "doris.http.port":"8030",
    "doris.query.port":"9030",
    "doris.database":"test_db",
    "key.converter":"org.apache.kafka.connect.storage.StringConverter",
    "value.converter":"org.apache.kafka.connect.json.JsonConverter"
  }
}'

Operation Connector

# View connector status
curl -i http://127.0.0.1:8083/connectors/test-doris-sink-cluster/status -X GET
# Delete connector
curl -i http://127.0.0.1:8083/connectors/test-doris-sink-cluster -X DELETE
# Pause connector
curl -i http://127.0.0.1:8083/connectors/test-doris-sink-cluster/pause -X PUT
# Restart connector
curl -i http://127.0.0.1:8083/connectors/test-doris-sink-cluster/resume -X PUT
# Restart tasks within the connector
curl -i http://127.0.0.1:8083/connectors/test-doris-sink-cluster/tasks/0/restart -X POST

Refer to: Connect REST Interface

note

Note that when kafka-connect is started for the first time, three topics config.storage.topic offset.storage.topic and status.storage.topic will be created in the kafka cluster to record the shared connector configuration of kafka-connect. Offset data and status updates. How to Use Kafka Connect - Get Started

Access an SSL-certified Kafka cluster

Accessing an SSL-certified Kafka cluster through kafka-connect requires the user to provide a certificate file (client.truststore.jks) used to authenticate the Kafka Broker public key. You can add the following configuration in the connect-distributed.properties file:

# Connect worker
security.protocol=SSL
ssl.truststore.location=/var/ssl/private/client.truststore.jks
ssl.truststore.password=test1234

# Embedded consumer for sink connectors
consumer.security.protocol=SSL
consumer.ssl.truststore.location=/var/ssl/private/client.truststore.jks
consumer.ssl.truststore.password=test1234

For instructions on configuring a Kafka cluster connected to SSL authentication through kafka-connect, please refer to: Configure Kafka Connect

Dead letter queue

By default, any errors encountered during or during the conversion will cause the connector to fail. Each connector configuration can also tolerate such errors by skipping them, optionally writing the details of each error and failed operation as well as the records in question (with varying levels of detail) to a dead-letter queue for logging.

errors.tolerance=all
errors.deadletterqueue.topic.name=test_error_topic
errors.deadletterqueue.context.headers.enable=true
errors.deadletterqueue.topic.replication.factor=1

Configuration items

Key	Default Value	Required	Description
name	-	Y	Connect application name, must be unique within the Kafka Connect environment
connector.class	-	Y	org.apache.doris.kafka.connector.DorisSinkConnector
topics	-	Y	List of subscribed topics, separated by commas. like: topic1, topic2
doris.urls	-	Y	Doris FE connection address. If there are multiple, separate them with commas. like: 10.20.30.1,10.20.30.2,10.20.30.3
doris.http.port	-	Y	Doris HTTP protocol port
doris.query.port	-	Y	Doris MySQL protocol port
doris.user	-	Y	Doris username
doris.password	-	Y	Doris password
doris.database	-	Y	The database to write to. It can be empty when there are multiple libraries. At the same time, the specific library name needs to be configured in topic2table.map.
doris.topic2table.map	-	N	The corresponding relationship between topic and table table, for example: topic1:tb1,topic2:tb2 The default is empty, indicating that topic and table names correspond one to one. The format of multiple libraries is topic1:db1.tbl1,topic2:db2.tbl2
buffer.count.records	10000	N	The number of records each Kafka partition buffers in memory before flushing to doris. Default 10000 records
buffer.flush.time	120	N	Buffer refresh interval, in seconds, default 120 seconds
buffer.size.bytes	5000000(5MB)	N	The cumulative size of records buffered in memory for each Kafka partition, in bytes, default 5MB
jmx	true	N	To obtain connector internal monitoring indicators through JMX, please refer to: Doris-Connector-JMX
enable.delete	false	N	Whether to delete records synchronously, default false
label.prefix	${name}	N	Stream load label prefix when importing data. Defaults to the Connector application name.
auto.redirect	true	N	Whether to redirect StreamLoad requests. After being turned on, StreamLoad will redirect to the BE where data needs to be written through FE, and the BE information will no longer be displayed.
load.model	stream_load	N	How to import data. Supports stream_load to directly import data into Doris; also supports copy_into to import data into object storage, and then load the data into Doris.
sink.properties.*	'sink.properties.format':'json', 'sink.properties.read_json_by_line':'true'	N	Import parameters for Stream Load. For example: define column separator 'sink.properties.column_separator':',' Detailed parameter reference here
delivery.guarantee	at_least_once	N	How to ensure data consistency when consuming Kafka data is imported into Doris. Supports at_least_once exactly_once, default is at_least_once. Doris needs to be upgraded to 2.1.0 or above to ensure data exactly_once

For other Kafka Connect Sink common configuration items, please refer to: connect_configuring