Package io.camunda.zeebe.engine.api

Interface RecordProcessor<CONTEXT>

All Known Implementing Classes:
Engine
public interface RecordProcessor<CONTEXT>
Interface for record processors. A record processor is responsible for handling a single record. (The class StreamProcessor in turn is responsible for handling a stream of records.

  • Method Details

    • init

      void init(CONTEXT recordProcessorContext)
      Called by platform to initialize the processor
      Parameters:
      recordProcessorContext - context object to initialize the processor

    • replay

      void replay(TypedRecord record)
      Called by platform in order to replay a single record

      Contract

      • Record will be an event
      • Will be called before processing is called
      • Implementors can write to the database. Transaction is provided by platform, which also takes care of lifecycle of the transaction
      • Implementors must not write to the log stream
      • Implementors must not schedule post commit tasks
      Parameters:
      record - the record to replay

    • process

      ProcessingResult process(TypedRecord record, ProcessingResultBuilder processingResultBuilder)
      Called by platform to process a single record

      Contract * *

        *
      • Record will be a command
      • Will be called after replay is called
      • Implementors can write to the database. Transaction is provided by platform, which also * takes care of lifecycle of the transaction
      • Implementors must ensure that if they generate follow up events, these are applied to the database while this method is called
      • Implementors can produce follow up commands and events, client responses and on commit tasks via processingResultBuilder
      • Implementors can indicate that the record should be skipped by returning EmptyProcessingResult.INSTANCE
      Returns:
      the result of the processing; must be generated via processingResultBuilder.build()

    • onProcessingError

      ProcessingResult onProcessingError(Throwable processingException, TypedRecord record, ProcessingResultBuilder processingResultBuilder)
      Called by platform when a processing error occurred
      Returns:
      the result of the processing; must be generated via ProcessingResultBuilder processingResultBuilder