Confusion about protoc for Javascript

[EricBuist]

Hi, I cannot figure out how to make use of the _pb.js files. Documentation at https://protobuf.dev/programming-guides/proto3/ doesn't include anything about Javascript or Node. Documentation on grpc.io refers to a protobuf loader that directly loads the .proto files. Trying to require a generated _pb.js file gives an object providing no methods to create a message from scratch, just to deserialize from binary, not even from JSON. This makes protoc pretty much useless for Javascript.

[dibenede]

https://github.com/protocolbuffers/protobuf-javascript/blob/main/docs/index.md#commonjs-imports might be a better starting point.

Assuming a message like:

message MyMessage {
  optional int32 foo = 1;
}

You should be able to construct from scratch:

const messages = require('./messages_pb');
const message = new messages.MyMessage();

message.setFoo(100);
console.log(message.getFoo());

const serialized = message.serializeBinary();
...

I'm not familiar with grpc specific aspects, however.