trpc-openapi VS protobuf-ts

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

DX for front or back end? The beauty of tRPC is that the types are derived/inferred from the backend runtime code (like, as you type). It would be nigh impossible to do that with grpc(-web) using proto files as the source of truth.

It's possible there's a project out there which could automatically produce proto files from something like zod, json-schema, etc. which could be directly interpreted by TS to provide similar (as you type) DX while still allowing some other language backend to consume the derived proto files (though the DX there would be less than ideal).

If you're just looking for similar TS clients/interfaces for grpc-web then I'd recommend https://github.com/timostamm/protobuf-ts which operates on plain JS objects (no new MyMessage().serialize(), instead the code generator mostly produces TS interfaces for you to work against: const myMessage: MyMessage = pojoConformingToInterface; const binary = MyMessage.toBinary(myMessage);)

https://github.com/timostamm/protobuf-ts (RpcMetaData) https://github.com/timostamm/protobuf-ts/blob/main/MANUAL.md

The second big difference is that we now have auto-generated client and server stubs. For this task, I chose to use buf and the protobuf-ts plugin in order to generate idiomatic Typescript classes and objects. Not only do these classes describe the types we'll use in the server and client, but also includes the actual gRPC implementations used to serialize and send messages back and forth across the wire.

I wouldn’t use grpc with web if you can avoid it. If you’re looking for a ts protobuf library I can recommend this one https://github.com/timostamm/protobuf-ts

https://github.com/timostamm/protobuf-ts looks interesting too.

I'd recommend looking into protobuf-ts (Timo from Buf) or protobuf-es (Buf maintained).

Use a GRPC library for frontend, assuming you want to go with Typescript take a look at https://github.com/timostamm/protobuf-ts Frontend frameworks like Angular/React/Vue don't define what and how to implement backend communication. You can use what you want and how you want it.

And there's also this which is by the same author but came before it: https://github.com/timostamm/protobuf-ts

The latter has code-generation for services and has various transport packages for twirp, grpc, and grpc-web.

This looks very interesting! Anything that can move people away from protobuf.js (which seems to no longer be maintained and depends on prototype values for "default values" meaning that you can't send deserialized protobuf messages to/from web workers) and the "native" JS codegen by Google (which produces code that is both very slow and a awkward to use) is a win in my book.

We're currently using https://github.com/timostamm/protobuf-ts which has been fantastic. It's codegen is dependent on the protoc binary as it is implemented as a protoc plugin, but the code it generates passes the protobuf conformance tests. The generated code also outputs plain objects when deserializing protobuf messages which means it works perfectly when sending stuff to/from web workers. It also has grpc, grpc-web, and twirp clients.