Why is `WebAPICallOptions` not type-safe?

[rr-codes]

Description

I recently encountered a bug that was due to using a non-existent property in ChatPostMessageArguments, which I assumed would not have been possible as it is a TypeScript interface. But such interface extends WebAPICallOptions, which allows any arbitrary key value pair, effectively removing its static type checking.

What type of issue is this? (place an x in one of the [ ])

• [ ] bug
• [ ] enhancement (feature request)
• [x] question
• [ ] documentation related
• [ ] testing related
• [ ] discussion

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

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

[mwbrooks]

Hi @rr-codes, this is a good question! My understanding is that the arbitrary keys were added for pagination support. Ideally, we would change it, but we must find a way to safely remove it from pagination. If we did, it would be a breaking change and need to be released in our next major version bump.

@kaz Since you're focused heavily on TS support right now, do you want to discuss this change more and possibly turn this into a task for the next major?

[seratch]

As an additional note,

If we did, it would be a breaking change and need to be released in our next major version bump.

if we decided to do this, we may want to apply the similar to WebAPICallResult.

[filmaj]

Closing this as a duplicate of #1323