Libs: make the payload parameter of create message generic, not "any" for all libs

[tasn]

In rust: should probably just be a generic over json serializable if it's not already.

For everything else (that supports generic): just make it generic. This will let people have more strict type checking.

[svix-onelson]

Did a survey of what's what right now.

• C# (typed as Object)
• Go (typed as map[string]interface{} which is probably fine)
• Java (typed as Object aka POJO)
• JavaScript (the ts type is currently any, 👎)
• Kotlin (typed as Any 👎, need to check to see how generics play with Json lib or otherwise switch to HashMap<String, Any>)
• PHP seems to not offer APIs for create message 🤷
• Python (typed as Dict[str, Any] which is probably okay)
• Ruby - not sure what to do here. Looks like we could add some runtime checks to the initializer but...
• Rust (typed as serde_json::Value which is okay but it would be better if it insisted on an Object variant)

I'm basing this assessment on the fact I thought the payload was meant to be an object, not any valid json value.
This is to say, I'd have expected it to be an error if I sent a create message request with:

{"eventType": "nonsense", "payload": false}

The object requirement not be the case according to our spec, but at least some of the code generators seem to be adhering to this.

A problem I see is the typing here is entirely in the hands of the OpenAPI codegen since this is a field on MessageIn. I need to learn more about how to influence what the generators spit out in each problem case.

[tasn]

@svix-onelson, I actually meant something, else, but what I meant didn't make sense. Though looking at your report, and given that it's based on MessageIn, I don't think there's anything sane we can do at this point. So maybe let's take a pause on this ticket?

[svix-onelson]

@tasn sounds good.

I think we're actually in pretty decent shape as things are. If I were to cherry-pick one of these, it'd be JS. Re-typing as {[key: string]: any} would bring things back inline with most of the others in the list.

[tasn]

Yeah, but changing the generation is a bit of a pita. I suspect that maybe updating the generator version, or maybe even fixing our spec (in case it's lacking) would be sufficient.