How can Kafka architecture be implemented to guarantee the one-time processing of each message?

To ensure guaranteed one-time processing of messages in Kafka, it is necessary to use a combination of several mechanisms:

1. Idempotent Producer — enable the enable.idempotence=true parameter in the producer settings. This guarantees that resending the same message will not lead to duplication in the topic.

2. Transactions — use a transactional producer (initTransactions(), beginTransaction(), commitTransaction(), abortTransaction()) for atomic message sending and processing confirmation. This is especially important if the producer writes to multiple topics or partitions.

3. Consumer with manual offset management — disable automatic offset committing (enable.auto.commit=false) and commit offsets only after successful message processing. This prevents loss or reprocessing.

4. Error handling and retries — implement retry logic with state control to avoid duplication.

Example of producer configuration with idempotence in Java:

Properties props = new Properties();
props.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, "localhost:9092");
props.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringSerializer");
props.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringSerializer");
props.put(ProducerConfig.ENABLE_IDEMPOTENCE_CONFIG, "true"); // Enable idempotence

KafkaProducer<String, String> producer = new KafkaProducer<>(props);

Thus, the combination of an idempotent producer, transactions, and manual offset management on the consumer side allows achieving guaranteed one-time message processing.