protocol-buffers

protocol-buffers

Encode/decode protocol buffers in node with stream support

npm install protocol-buffers

Usage

You should pass raw a .proto file as a buffer (or you can specify the schema as json). Per default the first message is used as the main one. Add an optional second argument to set it to a specific message

Assuming the following test.proto file exists

message Test {
  required float num  = 1;
  required string payload = 2;
}

var protobuf = require('protocol-buffers');
var schema = protobuf(fs.readFileSync('test.proto'));

var buf = schema.encode({
	num: 42,
	payload: 'hello world'
});

console.log(buf); // should print a buffer

var obj = schema.decode(buf);

console.log(obj); // should print an object similar to above

You can also stream the encoding/decodings

var encoder = schema.createEncodeStream();

encoder.write({
	num: 42,
	payload: 'hello world'
});

encoder.write({
	num: 43,
	payload: 'hello another world'
});

...

encoder.on('data', function(buf) {
	// buf is a buffer with the encoded object
});

And similarly if you wanted to decode

var decoder = schema.createDecodeStream();

decoder.write(buf);
decoder.on('data', function(obj) {
	// obj is an unpacked object
});

Note that each buffer passed to decoder.write should contain a full protobuf object so make sure you do some sort of delimiting/length-prefixing first

In addition to passing in a raw proto file you can also specify the schema as JSON

var schema = protobuf([{
	name: 'num',
	type: 'float'
}, {
	name: 'payload',
	type: 'bytes'
}, {
	name: 'some_nested_thing',
	type: 'object',
	fields: [{
		name: 'another_prop',
		type: 'string'
	}]
}]);

License

MIT