protobuf-ts VS reflect-metadata

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.

Counter to this post, as soon as I read the title I knew what this was, & I knew it was speaking exactly to something we've wanted for a long time. This is asking for more official & better supported https://github.com/rbuckton/reflect-metadata .

TypeScript is a compiler. It has a lot of type information during compilation. We could write that type information out into a file. Instead what we do is throw that information out when the compile ends. Taking all that typing information & throwing it away at the end of compile time is a bad dumb & silly limitation. Especially for a language like JavaScript, which historically could be semi-proud it had such a strong Everything Is An Object philosophy running through it (such as the malleable prototype-based inheritance system); so much type information should be on that Class object. Reflect-metadata for example defined new methods on Reflect to store this metadata.

I could not be more delighted to see the pennon of this website go up. We needed a rallying point for this. We needed a rallying point for keeping class data around. A rallying point for enriching the runtime with good actionable data is a good rallying point.

It's not what's afoot here, but I think you're a bit off-base about the impossibility of adding even some type-safety. We might not be able to get exact TS type safety. But we can definitely build some safety in. Owing to the malleable prototype-based type system in JS, we can add getters/setters to objects to do a lot of type checking. This doesn't even begin to explore the possibility of what we might do with es2015's proxies, which could allow even more interesting checks to be layered in. I also wish JS had an official AST (and renderer), so had more official options for code-rewriting that might let us weave in type checks.

What we can do as programmers is limited by what we have at our disposal. Not throwing out all the typing information, keeping it around at runtime, opens a lot of interesting doors.

Second, TypeScript 5.0 cannot emit decorator metadata. Subsequently, it doesn’t integrate with the Reflect API and won’t work with the reflect-metadata npm package.

Database columns will be mapped to domain object properties using decorators. This will include relationships and enum types. reflect-metadata stores metadata about the classes and properties. Most of the work is a simple map for each class, renaming db column properties to domain model properties and vice versa. Reflect.defineProperty holds a list of field metadata on the target class. This is where more database ORM logic could live in the future such as column type, length, etc. A base domain model entity will use this metadata to map the models appropriately.