vertx / io.vertx.kafka.client.consumer / KafkaReadStream

KafkaReadStream

interface KafkaReadStream<K : Any, V : Any> : ReadStream<ConsumerRecord<K, V>>

A ReadStream for consuming Kafka ConsumerRecord.

The #pause() and #resume() provides global control over reading the records from the consumer.

The #pause(Set) and #resume(Set) provides finer grained control over reading records for specific Topic/Partition, these are Kafka's specific operations.

Functions

assign

abstract fun assign(partitions: MutableSet<TopicPartition>): KafkaReadStream<K, V>

Manually assign a set of partitions to this consumer.

abstract fun assign(partitions: MutableSet<TopicPartition>, completionHandler: Handler<AsyncResult<Void>>): KafkaReadStream<K, V>

Manually assign a set of partitions to this consumer.

Due to internal buffering of messages, when reassigning the old set of partitions may remain in effect (as observed by the #handler(Handler) record handler)} until some time after the given completionHandler is called. In contrast, the once the given completionHandler is called the #batchHandler(Handler) will only see messages consistent with the new set of partitions.

assignment

abstract fun assignment(handler: Handler<AsyncResult<MutableSet<TopicPartition>>>): KafkaReadStream<K, V>

Get the set of partitions currently assigned to this consumer.

batchHandler

abstract fun batchHandler(handler: Handler<ConsumerRecords<K, V>>): KafkaReadStream<K, V>

Set the handler that will be called when a new batch of records is returned from Kafka. Batch handlers need to take care not to block the event loop when dealing with large batches. It is better to process records individually using the record handler.

beginningOffsets

abstract fun beginningOffsets(topicPartitions: MutableSet<TopicPartition>, handler: Handler<AsyncResult<MutableMap<TopicPartition, Long>>>): Unit

Get the first offset for the given partitions.

abstract fun beginningOffsets(topicPartition: TopicPartition, handler: Handler<AsyncResult<Long>>): Unit

Get the first offset for the given partition.

close

open fun close(): Unit
abstract fun close(completionHandler: Handler<AsyncResult<Void>>): Unit

Close the stream

commit

abstract fun commit(): Unit
abstract fun commit(completionHandler: Handler<AsyncResult<MutableMap<TopicPartition, OffsetAndMetadata>>>): Unit

Commit current offsets for all the subscribed list of topics and partition.

abstract fun commit(offsets: MutableMap<TopicPartition, OffsetAndMetadata>): Unit
abstract fun commit(offsets: MutableMap<TopicPartition, OffsetAndMetadata>, completionHandler: Handler<AsyncResult<MutableMap<TopicPartition, OffsetAndMetadata>>>): Unit

Commit the specified offsets for the specified list of topics and partitions to Kafka.

committed

abstract fun committed(topicPartition: TopicPartition, handler: Handler<AsyncResult<OffsetAndMetadata>>): Unit

Get the last committed offset for the given partition (whether the commit happened by this process or another).

create

open static fun <K : Any, V : Any> create(vertx: Vertx, config: Properties): KafkaReadStream<K, V>
open static fun <K : Any, V : Any> create(vertx: Vertx, config: Properties, keyType: Class<K>, valueType: Class<V>): KafkaReadStream<K, V>
open static fun <K : Any, V : Any> create(vertx: Vertx, config: MutableMap<String, Any>): KafkaReadStream<K, V>
open static fun <K : Any, V : Any> create(vertx: Vertx, config: MutableMap<String, Any>, keyType: Class<K>, valueType: Class<V>): KafkaReadStream<K, V>
open static fun <K : Any, V : Any> create(vertx: Vertx, consumer: Consumer<K, V>): KafkaReadStream<K, V>

Create a new KafkaReadStream instance

endOffsets

abstract fun endOffsets(topicPartitions: MutableSet<TopicPartition>, handler: Handler<AsyncResult<MutableMap<TopicPartition, Long>>>): Unit

Get the last offset for the given partitions. The last offset of a partition is the offset of the upcoming message, i.e. the offset of the last available message + 1.

abstract fun endOffsets(topicPartition: TopicPartition, handler: Handler<AsyncResult<Long>>): Unit

Get the last offset for the given partition. The last offset of a partition is the offset of the upcoming message, i.e. the offset of the last available message + 1.

listTopics

abstract fun listTopics(handler: Handler<AsyncResult<MutableMap<String, MutableList<PartitionInfo>>>>): KafkaReadStream<K, V>

Get metadata about partitions for all topics that the user is authorized to view.

offsetsForTimes

abstract fun offsetsForTimes(topicPartitionTimestamps: MutableMap<TopicPartition, Long>, handler: Handler<AsyncResult<MutableMap<TopicPartition, OffsetAndTimestamp>>>): Unit

Look up the offsets for the given partitions by timestamp.

abstract fun offsetsForTimes(topicPartition: TopicPartition, timestamp: Long, handler: Handler<AsyncResult<OffsetAndTimestamp>>): Unit

* Look up the offset for the given partition by timestamp.

partitionsAssignedHandler

abstract fun partitionsAssignedHandler(handler: Handler<MutableSet<TopicPartition>>): KafkaReadStream<K, V>

Set the handler called when topic partitions are assigned to the consumer

partitionsFor

abstract fun partitionsFor(topic: String, handler: Handler<AsyncResult<MutableList<PartitionInfo>>>): KafkaReadStream<K, V>

Get metadata about the partitions for a given topic.

partitionsRevokedHandler

abstract fun partitionsRevokedHandler(handler: Handler<MutableSet<TopicPartition>>): KafkaReadStream<K, V>

Set the handler called when topic partitions are revoked to the consumer

pause

abstract fun pause(topicPartitions: MutableSet<TopicPartition>): KafkaReadStream<K, V>

Suspend fetching from the requested partitions.

abstract fun pause(topicPartitions: MutableSet<TopicPartition>, completionHandler: Handler<AsyncResult<Void>>): KafkaReadStream<K, V>

Suspend fetching from the requested partitions.

Due to internal buffering of messages, the record handler will continue to observe messages from the given topicParations until some time after the given completionHandler is called. In contrast, the once the given completionHandler is called the #batchHandler(Handler) will not see messages from the given topicParations.

paused

abstract fun paused(handler: Handler<AsyncResult<MutableSet<TopicPartition>>>): Unit

Get the set of partitions that were previously paused by a call to #pause(Set).

pollTimeout

abstract fun pollTimeout(timeout: Long): KafkaReadStream<K, V>

Sets the poll timeout (in ms) for the underlying native Kafka Consumer. Defaults to 1000. Setting timeout to a lower value results in a more 'responsive' client, because it will block for a shorter period if no data is available in the assigned partition and therefore allows subsequent actions to be executed with a shorter delay. At the same time, the client will poll more frequently and thus will potentially create a higher load on the Kafka Broker.

position

abstract fun position(partition: TopicPartition, handler: Handler<AsyncResult<Long>>): Unit

Get the offset of the next record that will be fetched (if a record with that offset exists).

resume

abstract fun resume(topicPartitions: MutableSet<TopicPartition>): KafkaReadStream<K, V>
abstract fun resume(topicPartitions: MutableSet<TopicPartition>, completionHandler: Handler<AsyncResult<Void>>): KafkaReadStream<K, V>

Resume specified partitions which have been paused with pause.

seek

abstract fun seek(topicPartition: TopicPartition, offset: Long): KafkaReadStream<K, V>

Overrides the fetch offsets that the consumer will use on the next poll.

abstract fun seek(topicPartition: TopicPartition, offset: Long, completionHandler: Handler<AsyncResult<Void>>): KafkaReadStream<K, V>

Overrides the fetch offsets that the consumer will use on the next poll.

Due to internal buffering of messages, the record handler will continue to observe messages fetched with respect to the old offset until some time after the given completionHandler is called. In contrast, the once the given completionHandler is called the #batchHandler(Handler) will only see messages consistent with the new offset.

seekToBeginning

abstract fun seekToBeginning(topicPartitions: MutableSet<TopicPartition>): KafkaReadStream<K, V>

Seek to the first offset for each of the given partitions.

abstract fun seekToBeginning(topicPartitions: MutableSet<TopicPartition>, completionHandler: Handler<AsyncResult<Void>>): KafkaReadStream<K, V>

Seek to the first offset for each of the given partitions.

Due to internal buffering of messages, the record handler will continue to observe messages fetched with respect to the old offset until some time after the given completionHandler is called. In contrast, the once the given completionHandler is called the #batchHandler(Handler) will only see messages consistent with the new offset.

seekToEnd

abstract fun seekToEnd(topicPartitions: MutableSet<TopicPartition>): KafkaReadStream<K, V>

Seek to the last offset for each of the given partitions.

abstract fun seekToEnd(topicPartitions: MutableSet<TopicPartition>, completionHandler: Handler<AsyncResult<Void>>): KafkaReadStream<K, V>

Seek to the last offset for each of the given partitions.

Due to internal buffering of messages, the record handler will continue to observe messages fetched with respect to the old offset until some time after the given completionHandler is called. In contrast, the once the given completionHandler is called the #batchHandler(Handler) will only see messages consistent with the new offset.

subscribe

abstract fun subscribe(topics: MutableSet<String>): KafkaReadStream<K, V>

Subscribe to the given list of topics to get dynamically assigned partitions.

abstract fun subscribe(topics: MutableSet<String>, completionHandler: Handler<AsyncResult<Void>>): KafkaReadStream<K, V>

Subscribe to the given list of topics to get dynamically assigned partitions.

Due to internal buffering of messages, when changing the subscribed topics the old set of topics may remain in effect (as observed by the #handler(Handler) record handler}) until some time after the given completionHandler is called. In contrast, the once the given completionHandler is called the #batchHandler(Handler) will only see messages consistent with the new set of topics.

subscription

abstract fun subscription(handler: Handler<AsyncResult<MutableSet<String>>>): KafkaReadStream<K, V>

Get the current subscription.

unsubscribe

abstract fun unsubscribe(): KafkaReadStream<K, V>
abstract fun unsubscribe(completionHandler: Handler<AsyncResult<Void>>): KafkaReadStream<K, V>

Unsubscribe from topics currently subscribed with subscribe.

unwrap

abstract fun unwrap(): Consumer<K, V>