As with all other transports, the translation between EPL events and Kafka payloads is based on the choice of host plug-in and codecs. See Host plug-ins and configuration and Codec Connectivity Plug-ins for further information.

The default payload for the Kafka message is a string (with conversion from the underlying bytes using the classes StringDeserializer and StringSerializer from the org.apache.kafka.common.serialization package).

The following is a simple example of a YAML configuration file where the payload of the Kafka message will be the string form of the Apama event:

You can configure alternative serializers and deserializers using the consumerConfig and producerConfig options of the Kafka connectivity plug-in (see also Configuring the connection to Kafka (dynamicChainManagers). You can use a third-party serializer/deserializer implementation or you can create your own. You just need to include the relevant classes in the same classpath of the Kafka plug-in itself so that it can locate them. See the Kafka documentation for more information about Kafka serializers and deserializers. Additional transformations (for example, from a string containing JSON to a map) can be performed after the Kafka transport using connectivity codec plug-ins.