Package org.apache.pulsar.reactive.client.api

Interface ReactiveMessagePipelineBuilder<T>

Type Parameters:
T - the message payload type
All Known Subinterfaces:
ReactiveMessagePipelineBuilder.ConcurrentOneByOneMessagePipelineBuilder<T>, ReactiveMessagePipelineBuilder.OneByOneMessagePipelineBuilder<T>
public interface ReactiveMessagePipelineBuilder<T>
Builder interface for ReactiveMessagePipeline.

  • Method Details

    • messageHandler

      ReactiveMessagePipelineBuilder.OneByOneMessagePipelineBuilder<T> messageHandler(Function<org.apache.pulsar.client.api.Message<T>,org.reactivestreams.Publisher<Void>> messageHandler)

      Sets a handler function that processes messages one-by-one. When the message handler completes successfully, the message will be acknowledged. When the message handler emits an error, the error logger will be used to log the error and the message will be negatively acknowledged. If the error logger is not set, a default error message will be logged at the error level.

      NOTE: Be aware that negative acknowledgements on ordered subscription types such as Exclusive, Failover and Key_Shared typically cause failed messages to be sent to consumers out of their original order. Negative acknowledgements for Key_Shared subscriptions may also cause message delivery to be blocked on broker versions before Pulsar 4.0. To maintain ordered message processing, it is recommended to wrap the message handler with Project Reactor's native retry logic using Mono.retryWhen to retry processing of each message indefinitely with backoff.

      Parameters:
      messageHandler - a function that takes a message as input and returns an empty Publisher
      Returns:
      a builder for the pipeline handling messages one-by-one

    • streamingMessageHandler

      ReactiveMessagePipelineBuilder<T> streamingMessageHandler(Function<reactor.core.publisher.Flux<org.apache.pulsar.client.api.Message<T>>,org.reactivestreams.Publisher<MessageResult<Void>>> streamingMessageHandler)
      Sets a handler function that processes the stream of messages.
      Parameters:
      streamingMessageHandler - a function that takes a stream of messages as input and returns a MessageResult that contains the acknowledgement or negative acknowledgement value of the processing.
      Returns:
      the pipeline builder instance

    • transformPipeline

      ReactiveMessagePipelineBuilder<T> transformPipeline(Function<reactor.core.publisher.Mono<Void>,org.reactivestreams.Publisher<Void>> transformer)
      Sets a transform function that can be used to customize the pipeline.
      Parameters:
      transformer - a transform function
      Returns:
      the pipeline builder instance
      See Also:
      • Mono.transform(Function)

    • pipelineRetrySpec

      ReactiveMessagePipelineBuilder<T> pipelineRetrySpec(reactor.util.retry.Retry pipelineRetrySpec)
      Sets a retry spec that will be used in case of failures in the pipeline. The default is to retry indefinitely with an exponential backoff.
      Parameters:
      pipelineRetrySpec - the retry spec
      Returns:
      the pipeline builder instance
      See Also:
      • Mono.retryWhen(Retry)

    • build

      ReactiveMessagePipeline build()
      Builds the pipeline instance.
      Returns:
      the pipeline instance