Kafka API

Upstash uses Apache Kafka for deployments and provides a serverless Kafka cluster access using both native Kafka clients (over TCP) and REST API (over HTTP). As a consequence of this flexible model, there are some restrictions when using Kafka protocol, mainly for administrative Kafka APIs.

Currently following Kafka Protocol APIs are supported by Upstash:

NAME	KEY	NAME	KEY	NAME	KEY
Produce	0	DescribeGroups	15	EndTxn	26
Fetch	1	ListGroups	16	TxnOffsetCommit	28
ListOffsets	2	SaslHandshake	17	DescribeConfigs	32
Metadata	3	ApiVersions	18	AlterConfigs	33
OffsetCommit	8	CreateTopics	19	DescribeLogDirs	35
OffsetFetch	9	DeleteTopics	20	SaslAuthenticate	36
FindCoordinator	10	DeleteRecords	21	CreatePartitions	37
JoinGroup	11	InitProducerId	22	DeleteGroups	42
Heartbeat	12	OffsetForLeaderEpoch	23	IncrementalAlterConfigs	44
LeaveGroup	13	AddPartitionsToTxn	24	OffsetDelete	47
SyncGroup	14	AddOffsetsToTxn	25	DescribeCluster	60

Some of the unsupported Kafka APIs are in our roadmap to make them available. If you need an API that we do not support at the moment, please drop a note to [e-mail]. So we can inform you when we are planning to support it.

Connect Using Kafka Clients

Connecting to Upstash Kafka using any Kafka client is very straightforward. If you do not have a Kafka cluster and/or topic already, follow these steps to create one.

After creating a cluster and a topic, just go to cluster details page on the Upstash Console and copy bootstrap endpoint, username and password.

Then replace following parameters in the code snippets of your favourite Kafka client or language below.

• {{ BOOTSTRAP_ENDPOINT }}
• {{ UPSTASH_KAFKA_USERNAME }}
• {{ UPSTASH_KAFKA_PASSWORD }}
• {{ TOPIC_NAME }}

Create a Topic

Java

class CreateTopic {
  public static void main(String[] args) throws Exception {
    var props = new Properties();
    props.put("bootstrap.servers", "{{ BOOTSTRAP_ENDPOINT }}");
    props.put("sasl.mechanism", "SCRAM-SHA-512");
    props.put("security.protocol", "SASL_SSL");
    props.put("sasl.jaas.config", "org.apache.kafka.common.security.scram.ScramLoginModule required " +
                "username=\"{{ UPSTASH_KAFKA_USERNAME }}\" " +
                "password=\"{{ UPSTASH_KAFKA_PASSWORD }}\";");

    try (var admin = Admin.create(props)) {
        admin.createTopics(
            Set.of(new NewTopic("{{ TOPIC_NAME }}", partitions, replicationFactor))
          ).all().get();
    }
  }
}

Produce a Message

Java

class Produce {
  public static void main(String[] args) throws Exception {
    var props = new Properties();
    props.put("bootstrap.servers", "{{ BOOTSTRAP_ENDPOINT }}");
    props.put("sasl.mechanism", "SCRAM-SHA-512");
    props.put("security.protocol", "SASL_SSL");
    props.put("sasl.jaas.config", "org.apache.kafka.common.security.scram.ScramLoginModule required " +
                "username=\"{{ UPSTASH_KAFKA_USERNAME }}\" " +
                "password=\"{{ UPSTASH_KAFKA_PASSWORD }}\";");
    props.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
    props.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");

    try (var producer = new KafkaProducer<String, String>(props)) {
        producer.send(new ProducerRecord<>("{{ TOPIC_NAME }}", "Hello Upstash!"));
        producer.flush();
    }
  }
}

Consume Messages

Java

class Consume {
  public static void main(String[] args) throws Exception {
    var props = new Properties();
    props.put("bootstrap.servers", "{{ BOOTSTRAP_ENDPOINT }}");
    props.put("sasl.mechanism", "SCRAM-SHA-512");
    props.put("security.protocol", "SASL_SSL");
    props.put("sasl.jaas.config", "org.apache.kafka.common.security.scram.ScramLoginModule required " +
                "username=\"{{ UPSTASH_KAFKA_USERNAME }}\" " +
                "password=\"{{ UPSTASH_KAFKA_PASSWORD }}\";");

    props.put("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
    props.put("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
    props.put("auto.offset.reset", "earliest");
    props.put("group.id", "{{ GROUP_NAME }}");

    try(var consumer = new KafkaConsumer<String, String>(props)) {
        consumer.subscribe(Collections.singleton("{{ TOPIC_NAME }}"));
        var records = consumer.poll(Duration.ofSeconds(10));
        for (var record : records) {
            System.out.println(record);
        }
    }
  }
}