wsrpc 
node.js/browser protobuf rpc over binary websockets.
Minimal example
my-service.proto
service MyService {
rpc SayHello (HelloRequest) returns (HelloResponse) {}
}
message HelloRequest {
required string name = 1;
}
message HelloResponse {
required string text = 1;
}server.js
const wsrpc = require('wsrpc')
const protobuf = require('protobufjs')
const proto = protobuf.loadSync('my-service.proto')
const server = new wsrpc.Server(proto.lookupService('MyService'), { port: 4242 })
server.implement('sayHello', async (request) => {
return {text: `Hello ${ request.name }!`}
})client.js
const wsrpc = require('wsrpc')
const protobuf = require('protobufjs')
const proto = protobuf.loadSync('my-service.proto')
const client = new wsrpc.Client('ws://localhost:4242', proto.lookupService('MyService'))
const response = await client.service.sayHello({name: 'world'})
console.log(response) // Hello world!