use ProtoBuf.js?

[derhuerst]

related: derhuerst/hafas-gtfs-rt-feed#4

pbf parses missing optional fields as not missing and 0 (mafintosh/protocol-buffers#20).

One option is to use ProtoBuf.js using the --keep-case build flag.

const {Position} = require('gtfs-realtime-bindings').transit_realtime

const p = {latitude: 1.23, longitude: 2.34}
Position.verify(p)
// null
const buf = Position.encode(p).finish()
Position.decode(buf)
// Position {
//  latitude: 1.2300000190734863,
//  longitude: 2.3399999141693115
// }
Position.toObject(Position.decode(buf))
// { latitude: 1.2300000190734863, longitude: 2.3399999141693115 }