@dxos/codec-protobuf

Codec Protobuf

Codec for protobuf to use in libraries that follows the valueEncoding API of leveldb, like hypercore.

This module use a custom implementation of protobuf.js to support decode Buffers in the browser.

Install

$ npm install @dxos/codec-protobuf

Usage

syntax = "proto3";

message Task {
  string id = 1;
  string title = 2;
}

Using .proto files

import protobufjs from 'protobufjs';
import { Codec } from '@dxos/codec-protobuf';

const codec = new Codec('Task');

(async () => {
  // Load from a protobufjs root.
  codec
    .addJson(await protobufjs.load('schema.proto'))
    .build();

  const buffer = codec.encode({ id: 'task-0', title: 'test' });

  codec.decode(buffer); // { id: 'task-0', title: 'test' }
})();

Using JSON descriptors

import protobufjs from 'protobufjs';
import { Codec } from '@dxos/codec-protobuf';

const codec = new Codec('Task');

// Load from a JSON compiled proto schema.
codec
  .addJson(require('./schema.json'))
  .build();

const buffer = codec.encode({ id: 'task-0', title: 'test' });

codec.decode(buffer); // { id: 'task-0', title: 'test' }

API

const codec = new Codec(rootTypeUrl, [options])

Create a new CodecProtobuf instance.

The options are:

• rootTypeUrl: string: Defines the root type message to encode/decode messages. Required.
• options: Object
  • verify: boolean: Verify the objects before to encode. Default: true.
  • recursive: boolean: Recursively decode the buffer. Default: true.
  • strict: boolean: Throw an exception if the type is not found. Default: true.

codec.addJson(json) -> codec

Add the given JSON schema to the type dictionary.

• json: Object

codec.getType(type) -> (Type|null)

Get a type from the loaded schemas.

• type: string: Fully qualified type name.

codec.encode(data) -> Buffer

Encode an object using a specific protobuf type.

• data: Object

codec.decode(buffer) -> Object

• buffer: Buffer

Contributing

PRs accepted.

License

GPL-3.0 © dxos