trpc-openapi VS proposal-pattern-matching

tRPC does not natively export OpenAPI documents, but the trpc-openapi package adds this functionality. We'll start this tutorial by adding trpc-openapi to a project, and then we'll add a script to generate an OpenAPI schema and save it as a file.

While trpc-openapi originally was used to expose REST endpoints of the tRPC router, we will use it to generate an OpenAPI specification for our API.

Sure it can, you can use https://github.com/prosepilot/trpc-openapi

You either have to go with react native or use https://github.com/jlalmes/trpc-openapi to generate rest endpoint using trpc. lol. Not sure how good the trpc-openapi package is though. Read somewhere it was missing stuff

As for exposing the API externally, neither (can) limit this but SvelteKit's API is generally considered to be an internal implementation detail that you don't use directly since it might change between versions. If you want to expose an API you should choose tRPC, probably alongside the OpenAPI plugin or something similar.

In essence, features of the language made for static type checking at compilation are possibly being left favour of tools that act like a superset of the language that provide the static build type checking and offer runtime type checking too. An example I recently saw was the trpc-openapi package which uses Zod for creating the types of the schema for the http request and responses, it takes a zod schema as that is what it can use when compiled to JavaScript to generate the types for the openapi file at runtime, there's scarcely a type or interface in sight when using it but you have full type safety.

Take a look at https://github.com/jlalmes/trpc-openapi which will give you a rest endpoint based on your trpc router. Ymmv in reality but basically this should give you some confidence that your trpc router can be called from another client (not just next).

Ok thanks, I did find a good example here https://github.com/jlalmes/trpc-openapi/blob/master/examples/with-nextjs/src/server/router.ts

There is an OpenAPI Extension for tRPC that can be used to create a more REST-like API from your procedures, and that in turn can be used for auto-generating documentation. But if my app needed to offer third-party API access, I would likely reach for GraphQL again.

tRPC is nice because you have type safety the whole way down. Someone has made a tRPC OpenaAPI for exposing tRPC procedures externally in the OpenAPI format https://github.com/jlalmes/trpc-openapi

Note, however, that there is a proposal to add pattern matching to JS.

There's an ECMAScript proposal that is in the works to add this feature to the language! It's going to look something like this.

More importantly, TypeScript typically commits to build things into itself when the proposal in JavaScript reaches Stage 3. The pattern matching proposal in JavaScript is Stage 1, but depends on many other proposals as well that may or may not need to be at Stage 3 as well for it to work. This particular proposal is interested on pattern matching on JavaScript Objects and other primitives, just like Python does with it’s native primitives. These are also dynamic types which helps in some areas, but makes it harder than others. Additionally, the JavaScript type annotations proposal needs to possibly account for this. So it’s going to be awhile. Like many years.

For true™ functional programming in JS, native pattern matching and partial function application are missing (at least for now: 1, 2). For proper OOP, it lacks real interfaces and compile-time dependency injection.

The proposal for pattern matching syntax seems more akin to what they're looking for.

https://github.com/tc39/proposal-pattern-matching

There's a proposal to add something like that to JavaScript but it's been stuck in limbo since 2017 although there are libraries like ts-pattern which implement it already.

I'll admit, it is easy to assert that the TypeScript language should not be involved in the matters of packages but I also wonder if we're moving towards a point where interfaces will be as common as namespaces and whether or not it would be sensible for the language to incorporate such type assertions into the language formally, after all, it already compiles to various forms of JavaScript and there is a stage 1 proposal submitted to the TC39 committee to give JavaScript pattern matching. If adopted, wouldn't it make sense to allow TypeScript to compile a type into a type guard for the native JavaScript pattern matcher?

Both are active tc39 proposals :)

https://github.com/tc39/proposal-pipeline-operator - Stage 2

https://github.com/tc39/proposal-pattern-matching - Stage 1

Hopefully we get both in the next couple of years.

We often add promising TC39 proposals into Civet so people can experiment without waiting.

We've added https://github.com/tc39/proposal-pipeline-operator, a variant of https://github.com/tc39/proposal-pattern-matching, a variant of https://github.com/tc39/proposal-string-dedent and others.

Since our goal is to be 99% compatible with ES we'll need to accommodate any proposals that become standard and pick up anything TC39 leaves on the table (rest parameters in any position, etc.)