grpc-web VS protobuf-ts

* Additionally, client can stream data to the backend server (if bidirectional GRPC streams are used). I.e. client sends WebSocket messages, those will be transformed to GRPC messages by WebSocket server and delivered to the application backend.

As a result we have a system which allows to quickly create individual streams by using strict GRPC contract but terminating connections over WebSocket transport. So it works well in web browsers. After that no need to write WebSocket protocol, client implementation, handle WebSocket connection. This all will be solved by a suggested WebSocket server and its client SDKs.

The mechanics is similar to Websocketd (https://github.com/joewalnes/websocketd), but instead of creating OS processes we create GRPC streams. The difference from grpc-web (https://github.com/grpc/grpc-web) is that we provide streaming capabilities but not exposing GRPC contract to the client - just allowing to stream any data as payload (both binary and text) with some wrappers from our client SDKs side for managing subscriptions. I.e. it's not native GRPC streams on the client side - we expose just Connection/Subscription object to stream in both directions. GRPC streams used only for communication between WebSocket server and backend. To mention - grpc-web does not support all kinds of streaming now (https://github.com/grpc/grpc-web#streaming-support) while proposed solution can. This all should provide a cross-platform way to quickly write streaming apps due to client SDKs and language-agnostic nature of GRPC.

I personally see both pros and cons in this scheme (without concentrating on both too much here to keep the question short). I spent some time thinking about this myself, already have some working prototypes – but turned out need more opinions before moving forward with the idea and releasing this, kinda lost in doubts.

My main question - whether this seems interesting for someone here? Do you find this useful and see practical value?

By default, web browsers do not support gRPC, but we will use gRPC-web to make it possible.

You just have to use a library implementation for JavaScript https://github.com/grpc/grpc-web

TypeScript support remains an experimental feature of gRPC.

The gRPC-Web protocol supports HTTP/1 and can be used from a browser.

-- grpc-web

gRPC is mainly used in server-to-server communication, but it can also be used in client-to-server communication. gRPC-web is a gRPC implementation for web browsers. It is a JavaScript library that allows you to call gRPC services from a web browser. It supports Unary and Streaming Server API calls.

Since we're using Envoy, there's one more neat trick that we can employ. It turns out that Envoy also support gRPC-Web out of the box, a JavaScript client designed to support gRPC communication from the browser! That means that we can send gRPC messages over HTTP/1.1 as base64 encoded strings or as binary protobufs. Messages will be sent through our proxy and on to our backend service. The advantage of this is smaller and more efficient wire communication which should lead to better performance.

protoc-gen-grpc-web — a plugin that allows our front end to communicate with the backend using gRPC calls. A separate blog post on this coming up in the future.

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.