The following diagram shows how tenefit.cloud uses topic patterns to map between AMQP messages and Kafka messages.
Transforming AMQP messages to Kafka messages
AMQP topic patterns containing
$keycause Kafka messages to include a key matching the value for
$keyextracted from the AMQP topic name.
Publishing an AMQP message with an empty payload results in a Kafka message with a null value. Kafka topics configured for log compaction treat this as a tombstone for the corresponding message key.
Kafka headers prefixed with
$amqpare reserved for internal use, such as retention of message type information. AMQP messages published by AMQP clients should not include user properties with names prefixed by
Transforming Kafka messages to AMQP messages
AMQP subscribers receive Kafka messages filtered by message key. AMQP topic patterns containing
$keydeliver only Kafka messages with key matching
A Kafka message with a null or empty value is delivered as an AMQP message with an empty payload to AMQP subscribers.
Kafka header names prefixed by
$amqpare reserved for internal use, such as injection of message type information. They are removed before transformation and are not included in AMQP messages delivered to AMQP clients. Kafka messages produced by a Kafka producer should not contain headers with names prefixed by