Slack Bridge: Discontinuation of classic Slack App

[PieterCK]

:page_facing_up: Overview

Slack is discontinuing its classic Slack app. On June 4 2024, user won't be able to create the classic Slack app anymore.

This issue will highlight how this change will impact our "real-time slack mirror" feature, specifically bridge_with_slack.py and any relevant files.

Relevant links: Discontinuing new creation of Classic Slack apps and legacy custom integration bot users

Slack Migration Guide

CZO discussion: here.

:warning: Impacted Area

In summary, any ongoing mirrors using bridge_with_slack on a classic Slack app should continue to work. However, users won't be able to create new mirrors once the class Slack app has been discontinued because it uses RTM API. It is highly recommended by Slack to migrate to Socket Mode API.

see list of available API: slack_sdk

bridge_with_slack.py

If you're still using the RTM API, it means you haven't migrated to modern Slack apps yet, which don't support the RTM API. https://api.slack.com/changelog/2021-10-rtm-start-to-stop#events-sockets

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One recommended fix that seems to be the easiest is to just migrate to rtm.connect. However, RTM API itself must be configured using a classic Slack app. This means after June 4 2024, new Slack users won't be able to use our bridge_with_slack even when we've migrated to rtm.connect from rtm.start.

On the other hand, migrating to the recommended Socket Mode would likely require overhauling most of bridge_with_slack.py. However, this approach is more future-proof and allows the possibility to expand bridge_with_slack with more features provided by the Socket Mode API and other features down the line.

Documentation

Right now it's still pointing the user to create the classic Slack app.