Write to ConfluentCloud from Apache Beam (GCP Dataflow)

Question

I am trying to write to write to Confluent Cloud/Kafka from Dataflow (Apache Beam), using the following:

kafkaKnowledgeGraphKVRecords.apply("Write to Kafka", KafkaIO.<String, String>write()
                                .withBootstrapServers("<mybootstrapserver>.confluent.cloud:9092")
                                .withTopic("testtopic").withKeySerializer(StringSerializer.class)
                                .withProducerConfigUpdates(props).withValueSerializer(StringSerializer.class));

where Map<String, Object> props = new HashMap<>(); (ie empty for now)

In the logs, I get: send failed : 'Topic testtopic not present in metadata after 60000 ms.'

The topic does exist on this cluster - so my guess is that there is an issue with login, which makes sense as I couldn't find a way to pass the APIKey.

I did try various combinations to pass the APIKey/Secret I have from Confluent Cloud to auth with the props above but I couldn't find a working setup.

Answer 1

Found a solution, thanks to the pointers in the comments of @RobinMoffatt below the question

Here's the setup I have now:

Map<String, Object> props = new HashMap<>()

props.put("ssl.endpoint.identification.algorithm", "https");
props.put("sasl.mechanism", "PLAIN");
props.put("request.timeout.ms", 20000);
props.put("retry.backoff.ms", 500);
props.put("sasl.jaas.config","org.apache.kafka.common.security.plain.PlainLoginModule required username=\"<APIKEY>\" password=\"<SECRET>\";");
props.put("security.protocol", "SASL_SSL");

kafkaKnowledgeGraphKVRecords.apply("Write to Kafka-TESTTOPIC", KafkaIO.<String, String>write()
    .withBootstrapServers("<CLUSTER>.confluent.cloud:9092")
    .withTopic("test").withKeySerializer(StringSerializer.class)
    .withProducerConfigUpdates(props).withValueSerializer(StringSerializer.class));

The key line I had wrong is the sasl.jaas.config (note the ; at the end!)