Class KrabkaStreamsConfig

java.lang.Object

io.krabka.streams.KrabkaStreamsConfig

public final class KrabkaStreamsConfig
extends Object

Applies the client settings that a krabka streams group needs.

krabka brokers coordinate Kafka Streams applications through the streams group protocol. The only krabka-specific configuration step is to enable that protocol, which withDefaults(Map) does for you while leaving every setting you supply untouched.

Example

var settings = Map.<String, Object>of(
    StreamsConfig.APPLICATION_ID_CONFIG, "order-counter",
    StreamsConfig.BOOTSTRAP_SERVERS_CONFIG, "localhost:9092");

var streams = new KafkaStreams(topology, KrabkaStreamsConfig.withDefaults(settings));
streams.start();

To opt out of a default, set the key explicitly; explicit settings always win:

var settings = Map.<String, Object>of(
    StreamsConfig.APPLICATION_ID_CONFIG, "order-counter",
    StreamsConfig.BOOTSTRAP_SERVERS_CONFIG, "localhost:9092",
    KrabkaStreamsConfig.GROUP_PROTOCOL_CONFIG, "classic");

Field Summary

Fields

Modifier and Type	Field	Description
static final String	GROUP_PROTOCOL_CONFIG	The Kafka client configuration key that selects the group protocol.
static final String	STREAMS_GROUP_PROTOCOL	The group.protocol value that enables the streams group protocol.

Method Summary

Modifier and Type	Method	Description
static Properties	withDefaults(Map<?,?> settings)	Copies the supplied settings and adds krabka defaults.

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

GROUP_PROTOCOL_CONFIG

public static final String GROUP_PROTOCOL_CONFIG

The Kafka client configuration key that selects the group protocol.

See Also:

• Constant Field Values

STREAMS_GROUP_PROTOCOL

public static final String STREAMS_GROUP_PROTOCOL

The group.protocol value that enables the streams group protocol.

See Also:

• Constant Field Values

Method Details

withDefaults

public static Properties withDefaults(Map<?,?> settings)

Copies the supplied settings and adds krabka defaults. Explicit settings keep their values.

Currently the only default is GROUP_PROTOCOL_CONFIG set to STREAMS_GROUP_PROTOCOL. The supplied map is not modified.

Parameters:

settings - source settings, typically keyed by StreamsConfig constants

Returns:

an independent properties object

Throws:

NullPointerException - if settings is null