com.opendxl.databus.consumer

Class DatabusPushConsumer<P>

java.lang.Object

com.opendxl.databus.consumer.Consumer<P>

com.opendxl.databus.consumer.DatabusConsumer<P>

com.opendxl.databus.consumer.DatabusPushConsumer<P>

Type Parameters:

P - Message payload type

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

public final class DatabusPushConsumer<P>
extends DatabusConsumer<P>
implements java.io.Closeable

Extends a DatabusConsumer to replace poll model for push message model. pushAsync() reads messages from an already-subscribed topic and push them to a DatabusPushConsumerListener listener instance implemented by the SDK Databus client. The listener receives messages read from Databus and it should implement some logic to process them. The listener returns a DatabusPushConsumerListenerResponse enum value to let Push Databus Consumer known which action it should take.

Constructor Summary

Constructors

Constructor and Description
DatabusPushConsumer(java.util.Map<java.lang.String,java.lang.Object> configs, Deserializer<P> messageDeserializer, DatabusPushConsumerListener consumerListener) Constructor
DatabusPushConsumer(java.util.Map<java.lang.String,java.lang.Object> configs, Deserializer<P> messageDeserializer, DatabusPushConsumerListener consumerListener, Credential credential)
DatabusPushConsumer(java.util.Properties properties, Deserializer<P> messageDeserializer, DatabusPushConsumerListener consumerListener)
DatabusPushConsumer(java.util.Properties properties, Deserializer<P> messageDeserializer, DatabusPushConsumerListener consumerListener, Credential credential)

Method Summary

Modifier and Type	Method and Description
void	close() Close the consumer, waiting for up to the default timeout of 30 seconds for any needed cleanup.
ConsumerRecords	poll(java.time.Duration timeout) Fetch data for the topics or partitions specified using one of the subscribe/assign APIs.
ConsumerRecords	poll(long timeout) Fetch data for the topics or topicPartitions specified using one of the subscribe/assign APIs.
DatabusPushConsumerFuture	pushAsync() Reads messages from Databus and push them to DatabusPushConsumerListener instance which was passed in the constructor
DatabusPushConsumerFuture	pushAsync(java.time.Duration timeout) Reads messages from Databus and push them to DatabusPushConsumerListener instance which was passed in the constructor

Methods inherited from class com.opendxl.databus.consumer.Consumer

assign, assignment, beginningOffsets, bytesFetchRequestSizeAvgMetric, bytesPerSecondAvgMetric, bytesTotalMetric, close, commitAsync, commitAsync, commitAsync, commitSync, commitSync, committed, endOffsets, fetchRequestAvgMetric, listTopics, metrics, offsetsForTimes, partitionsFor, pause, paused, position, recordsLagAvgPerTopicPartition, recordsLagMaxMetric, recordsLagMaxPerTopicPartition, recordsLagPerTopicPartition, recordsPerRequestAvgMetric, recordsPerSecondAvgMetric, recordsTotalMetric, resume, seek, seekToBeginning, seekToEnd, subscribe, subscribe, subscribe, subscribe, subscribe, subscription, totalFetchRequestMetric, unsubscribe, wakeup

Methods inherited from class java.lang.Object

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

Constructor Detail

DatabusPushConsumer

public DatabusPushConsumer(java.util.Map<java.lang.String,java.lang.Object> configs,
                           Deserializer<P> messageDeserializer,
                           DatabusPushConsumerListener consumerListener)

Constructor

Parameters:

configs - consumer configuration

messageDeserializer - consumer message deserializer

consumerListener - consumer listener

DatabusPushConsumer

public DatabusPushConsumer(java.util.Map<java.lang.String,java.lang.Object> configs,
                           Deserializer<P> messageDeserializer,
                           DatabusPushConsumerListener consumerListener,
                           Credential credential)

Parameters:

configs - consumer configuration

messageDeserializer - consumer message deserializer

consumerListener - consumer listener

credential - credential to get access to Databus in case security is enabled

DatabusPushConsumer

public DatabusPushConsumer(java.util.Properties properties,
                           Deserializer<P> messageDeserializer,
                           DatabusPushConsumerListener consumerListener)

Parameters:

properties - consumer configuration

messageDeserializer - consumer message deserializer

consumerListener - consumer listener

DatabusPushConsumer

public DatabusPushConsumer(java.util.Properties properties,
                           Deserializer<P> messageDeserializer,
                           DatabusPushConsumerListener consumerListener,
                           Credential credential)

Parameters:

properties - consumer configuration

messageDeserializer - consumer message deserializer

consumerListener - consumer listener

credential - credential to get access to Databus in case security is enabled

Method Detail

poll

public ConsumerRecords poll(java.time.Duration timeout)

Fetch data for the topics or partitions specified using one of the subscribe/assign APIs. It is an error to not have subscribed to any topics or partitions before polling for data.

On each poll, consumer will try to use the last consumed offset as the starting offset and fetch sequentially. The last consumed offset can be manually set through Consumer.seek(TopicPartition, long) or automatically set as the last committed offset for the subscribed list of partitions

This method returns immediately if there are records available. Otherwise, it will await the passed timeout. If the timeout expires, an empty record set will be returned. Note that this method may block beyond the timeout in order to execute custom ConsumerRebalanceListener callbacks.

Overrides:

poll in class Consumer<P>

Parameters:

timeout - The time, in milliseconds, spent waiting in poll if data is not available. If 0, returns immediately with any records that are available now. Must not be negative.

Returns:

map of topic to records since the last fetch for the subscribed list of topics and topicPartitions

poll

public ConsumerRecords poll(long timeout)

Fetch data for the topics or topicPartitions specified using one of the subscribe/assign APIs. It is an error to not have subscribed to any topics or topicPartitions before polling for data.

On each poll, consumer will try to use the last consumed offset as the starting offset and fetch sequentially. The last consumed offset can be manually set through Consumer.seek(TopicPartition, long) or automatically set as the last committed offset for the subscribed list of topicPartitions

Overrides:

poll in class Consumer<P>

Parameters:

timeout - The time, in milliseconds, spent waiting in poll if data is not available. If 0, returns immediately with any records that are available now. Must not be negative.

Returns:

map of topic to records since the last fetch for the subscribed list of topics and topicPartitions

pushAsync

public DatabusPushConsumerFuture pushAsync(java.time.Duration timeout)

Reads messages from Databus and push them to DatabusPushConsumerListener instance which was passed in the constructor

Parameters:

timeout - The time, in milliseconds, spent waiting in poll if data is not available. If 0, returns immediately with any records that are available now. Must not be negative.

Returns:

Future to monitoring the message processing

Throws:

DatabusClientRuntimeException - if DatabusPushConsumeris closed.

pushAsync

public DatabusPushConsumerFuture pushAsync()

Reads messages from Databus and push them to DatabusPushConsumerListener instance which was passed in the constructor

Returns:

Future to monitoring the message processing

close

public void close()

Close the consumer, waiting for up to the default timeout of 30 seconds for any needed cleanup. If auto-commit is enabled, this will commit the current offsets if possible within the default timeout. See Consumer.close(Duration) for details. Note that Consumer.wakeup() cannot be used to interrupt close.

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

Overrides:

close in class Consumer<P>