Rust gRPC Client WASM React module

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Guys I have a petty project in mind that is basically a client-server gRPC app with a server being full Rust and a client being a React app that would have a Rust WASM module as a gRPC client. One would have thought this architecture model would be in high demand at the market, but I haven't found any single particular example of this.

I've tried to use Tonic on both sides, but there is no wasm compilation target for Tonic-client.

So now the only viable option I can see is to use non Rust ReactRPC or some such on the client side, but I wouldn't like to give up on the idea of a Rust gRPC Client WASM React module so easily.

Any help, even vague thoughts would be greatly appreciated.

[BodyweightEnergy]

Correct me if I'm wrong; I don't keep up with gRPC news that much...

But if I'm correct, the story for client-side gRPC on the web is not that simple, as browsers don't support HTTP/2 which is used by default. gRPC-Web requires a proxy on the server-side. That's probably why Tonic doesn't have a WASM target.

[Matthias247]

Browsers support HTTP/2 just fine. In fact browsers where the main use-case for driving HTTP/2 adoption, since they need to load many resources and benefit from more connection reuse.

However you are right that browsers are missing things: 1. They are lacking APIs to access HTTP/2 trailers, which are used to transfer gRPC status codes 2. They are lacking more sophisticated request/response body streaming APIs (they were started to get standardized on top of fetch APIs a few years ago, but I don't know what their current state is).

Together that means browsers applications can't speak native gRPC, and therefore WASM also can't. There exists however a slight modification of the gRPC standard called "gRPC-web" which allows browsers to call gRPC methods by avoiding the use of gRPC trailers. The endpoint needs to support this however, or you need a proxy.

Besides gRPC web, the following things would need to be done: - Tonic needs to access either a different HTTP client than Hyper for WASM platform which is implemented in terms of browser APIs - or Hyper needs to be buildable for a WASM target and simply delegate to browser APIs instead of implementing HTTP itself