Allow App's listener_executor to be supplied to __init__

[chrisbouchard]

It would be helpful to be able to supply my own executor to my Bolt app. For my particular use-case, I would like to use an executor from Flask-Executor for an app running in Flask, so that my listener functions automatically run with the current request context.

Additionally, it would allow users to configure the number of threads and the threading strategy (min threads, max threads, etc.).

I would be willing to create a pull request for this feature if it's acceptable. I suspect all that would be required is a new keyword-only parameter to App.__init__. We could fall back to the existing behavior if it's None.

My current work-around is to monkey-patch the executors in ThreadListenerRunner and ThreadLazyListenerRunner. Not difficult, but not future-proof.

Category (place an x in each of the [ ])

• slack_bolt.App and/or its core components
• slack_bolt.async_app.AsyncApp and/or its core components
• Adapters in slack_bolt.adapter
• Others

Requirements

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[seratch]

Hi @chrisbouchard, thanks for writing in! I agree that enabling developers to custom the part in a safe way is a good addition in future versions.