protobuf example

gps.proto

package gps;
syntax = "proto3";

message gps {
  message V {
    double lng = 0;
    double lat = 1;
    double acc = 2;
    double alt = 3;
    double spd = 4;
    double hdg = 5;
  }
  V v = 0;
  double ts = 1;
}

proto.js

var protobuf = require("protobufjs");

protobuf.load("gps.proto", function(err, root) {
    if (err)
        throw err;
 
    // Obtain a message type
    var GpsMessage = root.lookupType("gps.gps");
 
    // Exemplary payload
    var payload = {
      "v": {
        "lng": 10.414394,
        "lat": 63.430588,
        "acc": 17.127758,
        "alt": 221.639832,
        "spd": 0.320966,
        "hdg": 0
      },
      "ts": 1566042672382
    };
 
    // Verify the payload if necessary (i.e. when possibly incomplete or invalid)
    var errMsg = GpsMessage.verify(payload);
    if (errMsg)
        throw Error(errMsg);
 
    // Create a new message
    var message = GpsMessage.create(payload); // or use .fromObject if conversion is necessary
 
    // Encode a message to an Uint8Array (browser) or Buffer (node)
    var buffer = GpsMessage.encode(message).finish();
    // ... do something with buffer
    console.log(buffer.toString().length) // 62
});