protobufjs

What is protobufjs?

The protobufjs npm package provides a comprehensive suite of tools for working with Protocol Buffers (protobuf), a method of serializing structured data. It allows users to encode and decode protobuf messages, generate and work with static code, and handle dynamic message building and parsing.

What are protobufjs's main functionalities?

Loading .proto files

This feature allows users to load .proto files and use the defined protobuf structures within their JavaScript code.

const protobuf = require('protobufjs');
protobuf.load('awesome.proto', function(err, root) {
  if (err) throw err;
  const AwesomeMessage = root.lookupType('awesomepackage.AwesomeMessage');
  // ... use AwesomeMessage
});

Encoding and decoding messages

With protobufjs, users can encode JavaScript objects into binary protobuf format and decode binary messages into JavaScript objects.

const message = AwesomeMessage.create({ awesomeField: 'AwesomeString' });
const buffer = AwesomeMessage.encode(message).finish();
const decodedMessage = AwesomeMessage.decode(buffer);

Reflection and runtime message building

This feature allows users to work with protobuf messages dynamically at runtime using JSON descriptors, without the need for generated static code.

const root = protobuf.Root.fromJSON(jsonDescriptor);
const AwesomeMessage = root.lookupType('awesomepackage.AwesomeMessage');
const errMsg = AwesomeMessage.verify({ awesomeField: 'AwesomeString' });
if (errMsg) throw Error(errMsg);
const message = AwesomeMessage.create({ awesomeField: 'AwesomeString' });

Static code generation

Protobufjs can generate static code from .proto files, which can be used for better performance and type safety.

protobuf.load('awesome.proto', function(err, root) {
  if (err) throw err;
  protobuf.codegen(root, { keepCase: true }, function(err, output) {
    if (err) throw err;
    // output will contain the generated static code
  });
});

Other packages similar to protobufjs

@apollo/protobufjs

This is a fork of the original protobufjs package with some modifications. It is used within the Apollo tooling ecosystem but generally offers similar functionality to protobufjs.

google-protobuf

This is the official Protocol Buffers runtime library for JavaScript. It is provided by Google and offers similar serialization and deserialization capabilities. However, it may not be as feature-rich or flexible as protobufjs in terms of dynamic message handling and may require more setup for code generation.

pbf

Pbf is a fast, lightweight Protocol Buffers implementation in JavaScript. It focuses on performance and is smaller in size compared to protobufjs. However, it might not offer the same level of functionality, especially in terms of reflection and dynamic message building.

README

protobuf.js 5

Protocol Buffers are a language-neutral, platform-neutral, extensible way of serializing structured data for use in communications protocols, data storage, and more, originally designed at Google (see).

protobuf.js is a pure JavaScript implementation on top of bytebuffer.js including a .proto parser, message class building and simple encoding and decoding. There is no compilation step required, it's super easy to use and it works out of the box on .proto files!

Getting started

• Step 1: Become familar with Google's Protocol Buffers (protobuf)
• Step 2: Read on or head straight to our wiki for additional information
• Step 3: Build something cool! :-)

Features

• RequireJS/AMD compatible
• node.js/CommonJS compatible, also available via npm
• Browser compatible
• Closure Compiler compatible (fully annotated, externs)
• Fully documented using jsdoc3
• Well tested through test.js
• bytebuffer.js is the only production dependency
• Fully compatible to the official implementation including advanced features
• proto2js command line utility

Installation

node.js / CommonJS

$> npm install protobufjs

var ProtoBuf = require("protobufjs");
...

RequireJS / AMD

Requires bytebuffer.js. Optionally depends on long.js for long (int64) support. If you do not require long support, you can skip the Long.js config. RequireJS example:

require(["protobuf"], function(ProtoBuf) {
    ...
});

Or as a module dependency:

define("MyModule", ["protobuf"], function(ProtoBuf) {
    ...
});

Browser

Requires bytebuffer.js. Optionally depends on long.js for long (int64) support. If you do not require long support, you can skip the Long.js include.

<!-- Order is important -->
<script src="long.min.js"></script>
<script src="bytebuffer.min.js"></script>
<script src="protobuf.min.js"></script>

var ProtoBuf = dcodeIO.ProtoBuf;
...

Getting started

Note: You'll need the full build to load .proto data. light builds are able to load JSON only.

Loading .proto files

To load a .proto file, use:

API: ProtoBuf.loadProtoFile(source[, callback[, builder]]):Builder|undefined

// Synchronously
var builder = ProtoBuf.loadProtoFile("path/to/file.proto");

// Asynchronously
ProtoBuf.loadProtoFile("path/to/file.proto", function(err, builder) {
    ...
});

ProtoBuf.loadProtoFile also accepts an object specifying the import root directory and the file to load as its first parameter: {root: string, file: string}. Additionally, an already created and then reused builder can be specified as the last argument, which is useful if all the definitions shall reside in a single namespace.

Loading .proto strings

API: ProtoBuf.loadProto(source[, builder][, filename]):Builder

var builder = ProtoBuf.loadProto(...protoString..., "myproto.proto");

Loading JSON files and strings

To load the (raw) JSON counterpart generated through pbjs, use ProtoBuf.loadJsonFile respectively ProtoBuf.loadJson. It's the same API.

If you generated classes or modules with it, loading is done just by including respectively requiring the resulting file. Loading is handled transparently in this case.

When using JSON only, you can use protobuf-light.js or protobuf-light.min.js instead, which do NOT include the ProtoBuf.DotProto package for parsing and are therefore smaller.

Command line

Since ProtoBuf.js 4.0.0 the library ships with the pbjs command line utility. With it it's possible to convert between .proto and JSON descriptors and even to generate the code required to access runtime structures as pure JS (classes), an AMD module or a CommonJS module.

 _ |_ . _
|_)|_)|_)           ProtoBuf.js v4.0.0-b3 https://github.com/dcodeIO/ProtoBuf.js
|     '

CLI utility to convert between .proto and JSON syntax / to generate classes.

Usage: pbjs <filename> [options] [> outFile]

Options:
  --help, -h        Show help  [boolean]
  --version, -v     Show version number  [boolean]
  --source, -s      Specifies the source format. Valid formats are:

                       json       Plain JSON descriptor
                       proto      Plain .proto descriptor

  --target, -t      Specifies the target format. Valid formats are:

                       amd        Runtime structures as AMD module
                       commonjs   Runtime structures as CommonJS module
                       js         Runtime structures
                       json       Plain JSON descriptor
                       proto      Plain .proto descriptor

  --using, -u       Specifies an option to apply to the volatile builder
                    loading the source, e.g. convertFieldsToCamelCase.
  --min, -m         Minifies the output.  [default: false]
  --path, -p        Adds a directory to the include path.
  --legacy, -l      Includes legacy descriptors from google/protobuf/ if
                    explicitly referenced.  [default: false]
  --quiet, -q       Suppresses any informatory output to stderr.  [default: false]
  --use, -i         Specifies an option to apply to the emitted builder
                    utilized by your program, e.g. populateAccessors.
  --exports, -e     Specifies the namespace to export. Defaults to export
                    the root namespace.
  --dependency, -d  Library dependency to use when generating classes.
                    Defaults to 'protobufjs' for CommonJS, 'ProtoBuf' for
                    AMD modules and 'dcodeIO.ProtoBuf' for classes.

Documentation

• Read the official protobuf guide
• Read the API docs
• Check out the examples

Tests

• View source

Downloads

• Distributions
• ZIP-Archive
• Tarball

CDN usage

<script src="//cdn.rawgit.com/dcodeIO/protobuf.js/5.0.1/dist/protobuf.min.js"></script>

With the version pointing to the exact release your project depends upon.

License: Apache License, Version 2.0