handler-core

handler-core

Library with base components for building a new service for handling events from the dispatch-service

Usage

Add this package as dependency:

<dependency>
    <groupId>de.muenchen.oss.swim</groupId>
    <artifactId>handler-core</artifactId>
    <version></version>
</dependency>

Create a custom implementation of the ProcessFileInPort interface.

Provided Out Ports

This package also provides following out ports with default functionality:

• FileSystemOutPort:
  • Download a file from S3 via presigned URL
• FileEventOutPort:
  • Send a file finished event to the dispatch-service, which tags and moved the file for later cleanup in the S3
  • Needs to be called after successfully processing in the custom ProcessFileInPort implementation
  • For sending the according event, call the fileFinished method with the incoming event as argument

Error handling

The dispatch-service provides an inbound topic for handling errors which occur during processing. To use this functionality the Dead-Letter-Queue (dlq) needs to be configured for the incoming Consumer binding (See Configuration).

After accordingly configured, all thrown exceptions are forwarded to the dispatch service, which handles them by sending a notification to the contact person of the corresponding use case and logging the error message.

Configuration

spring:
  cloud:
    stream:
      kafka:
        binder:
          brokers: localhost:29092
          configuration:
            security:
              protocol: PLAINTEXT
        bindings:
          # use dispatch-service error handling for incoming events (optional)
          event-in-0:
            consumer:
              enable-dlq: true
              dlq-name:
      bindings:
        # incoming events
        event-in-0:
          group:
          destination:
        # finished event out
        finished-out:
          destination: