RTM message format has changed, verify eventWrapper assumptions

[aoberoi]

Description

We've noticed some changes in the RTM message format but have not actively updated the processing of each event in eventWrapper accordingly. It's possible that some of the assumptions made are no longer valid. That was the case in #586 - since bot_message events started having a user property the logic behind when to update the botUserIdMap was no longer correct.

A few more things to check:

• Do we still need a botUserIdMap? I think yes, because the user ID of the bot is not enough information to put in the message.user object, otherwise there will be breaking changes. However, we also see a bot_profile on some (maybe all) events now - is that enough?
• What happened to the subtype: 'bot_message'? It seems to be missing on at least some, but maybe all, events where it should be.
• Is there a new property that can be used to know that a message was sent from Slackbot?

This is not an exhaustive list, and we should look for more changes we may need to make to eventWrapper.

Related to #588

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

• I've read and understood the Contributing guidelines and have done my best effort to follow them.
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• I've searched for any related issues and avoided creating a duplicate issue.

[seratch]

Do we still need a botUserIdMap? I think yes, because the user ID of the bot is not enough information to put in the message.user object, otherwise there will be breaking changes.

I also think - yes, we do. The cache is necessary to provide full information about bot users.

However, we also see a bot_profile on some (maybe all) events now - is that enough?

This may be also true. That said, for the forthcoming patch releases, I don't want to introduce any breaking changes.

If we all are on the same page regarding this, we can safely merge my PR #588 and release a new patch version to address #586 .

[github-actions]

👋 It looks like this issue has been open for 30 days with no activity. We'll mark this as stale for now, and wait 10 days for an update or for further comment before closing this issue out.