Cannot resolve dependency 'http2' with grpc and grpc-transport

[JordanGreissman]

Trying to install @protobuf-ts/grpc-transport in an app that uses create-react-app, I get cannot resolve dependency 'http2'. It looks like create-react-app defines an empty mock for http2 in its webpack config, and trying to manually install http2 leads to a critical dependency error: Critical dependency: require function is used in a way in which dependencies cannot be statically extracted.

Issues in the grpc-js and create-react-app repos (here and here) imply that this has been solved in the version of both that I'm installing, so I'm unsure what to do. Has anyone encountered this?

node version: 14.16.0
npm version: 6.14.11
create-react-app version: 3.4.4

[timostamm]

Just in case: gRPC doesn't work in the browser. I assume you want to do server side rendering?

The issue seems to be: @protobuf-ts/grpc-transport uses the package @grpc/grpc-js as the gRPC implementation. @grpc/grpc-js requires the Node.js built-in module http2. You cannot install it, you either get it with Node.js, or you don't have it.

Converting to a discussion, since this is not really an issue with protobuf-ts. Hope a helpful answer turns up.

[parkwherever]

Dumb question: can you help me understand what prevents gRPC from working in the browser. Most modern versions of browsers support http2 right?

Related - if gRPC doesn't work in the browser, given your familiarity here, what is your recommendation to implement bi-directional streaming between the browser and a backend?

[timostamm]

Browsers do not expose trailers to JavaScript, but trailers are essential for gRPC, because that's where it puts the status.

It's sad, really. You can actually make fetch requests to a gRPC service, but you would never know if the service reported an error status, so it's impractical.

Client streams are also not well supported. See this article for details.

The first step in implementing bidi streaming is to ask yourself if you really need it, or if you can actually model the problem with a server streaming method. If you cannot, I recommend to look at WebSockets. They have very good browser support, and you could implement a websocket transport for protobuf-ts. See here for how improbable does it.