Akka: Adding a delay to a durable mailbox

Question

I am wondering if there is some way to delay an akka message from processing?

My use case: For every request I have, I have a small amount of work that I need to do and then I need to additional work two hours later.

Is there any easy way to delay the processing of a message in AKKA? I know I can probably setup an external distributed queue such as ActiveMQ, RabbitMQ which probably has this feature but I rather not.

I know I would need to make the mailbox durable so it can survive restarts or crashes. We already have mongo setup so I probably be using the MongoBasedMailbox for durability.

Answer 1

Temporal Workflow is capable of supporting your use case with minimal effort. You can think about it as a Durable Actor platform. When actor state including threads and local variables is preserved across process restarts.

Temporal offers a lot of other features for task processing.

• Built it exponential retries with unlimited expiration interval
• Failure handling. For example, it allows executing a task that notifies another service if both updates couldn't succeed during a configured interval.
• Support for long running heartbeating operations
• Ability to implement complex task dependencies. For example to implement chaining of calls or compensation logic in case of unrecoverable failures (SAGA)
• Gives complete visibility into the current state of the update. For example, when using queues all you know if there are some messages in a queue and you need additional DB to track the overall progress. With Temporal every event is recorded.
• Ability to cancel an update in flight.
• Throttling of requests

See the presentation that goes over the Temporal programming model. It talks about Cadence which is the predecessor of Temporal.