Strongly typed client

[neekolas]

Summary

A long-standing source of frustration with our JS SDK is the use of any types for message content. Sending and receiving messages has the content field typed as any.

Message content is of a finite set of types, defined by the codecs that get passed in to Client creation. If you have a codec that returns number, it's possible to get messages with content of type number. If you don't a number codec, it's not possible.

We just need to do some Typescript wrangling to infer those types from the codecs and pass them around to all the conversation methods.

This PR does that.

Notes

I've structured this to be safe for existing implementers. All the existing types default to any. This will make the migration path smoother for developers, but also may lead devs to not take advantage of this feature.

// This will have strong typing
const goodClient = await Client.create(someWallet)
const goodConvo = await goodClient.conversations.newConversation(someAddress)
// Will cause a type error because the client is set to have a type of "string"
await goodConvo.send(1234)

// Coerce the type of Client to the default
let badClient: Client
badClient = await Client.create(someWallet)
const badConvo = await badClient.conversations.newConversation(someAddress)
// The type-checker will ignore this, because Client is set to the default of any
await badConvo.send(1234)

// This will also disable the strong typing
const otherBadConvo: Conversation = await goodClient.conversations.newConversation(someAddress)
// This will be allowed
await otherBadConvo.send(1234)

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[rygine]

some nits, but nothing blocking. great work, LGTM!

[github-actions]

🎉 This PR is included in version 11.0.0-beta.11 🎉

The release is available on:

• npm package (@beta dist-tag)
• GitHub release

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