# pull-length-prefixed

> Streaming length prefixed buffers with pull-streams

Latest version **1.3.3** (published 2019-05-03) · MIT license · 0 weekly downloads

## Install

```sh
npm install pull-length-prefixed
pnpm add pull-length-prefixed
yarn add pull-length-prefixed
bun add pull-length-prefixed
```

## Health

**Score 15/100 (F)** — status: abandoned.

Positive: no vulnerabilities.

Warnings: low downloads; no types; no esm support.

Negative: abandoned; low maintenance score.

## Facts

| | |
|---|---|
| Version | 1.3.3 |
| Published | 2019-05-03 |
| First published | 2016-06-13 |
| Weekly downloads | 0 |
| License | MIT |
| TypeScript types | none |
| Module format | CommonJS |
| Dependencies | 4 |
| Unpacked size | 341.5 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| GitHub stars | 9 |
| Author | Friedel Ziegelmayer |
| Maintainers | dignifiedquire |
| Keywords | varint, pull-stream, length-prefixed-stream, length-prefixed |

## Links

- npm: https://www.npmjs.com/package/pull-length-prefixed
- Repository: https://github.com/dignifiedquire/pull-length-prefixed
- Homepage: https://github.com/dignifiedquire/pull-length-prefixed#readme
- Issues: https://github.com/dignifiedquire/pull-length-prefixed/issues
- npm.io page: https://npm.io/package/pull-length-prefixed

## Dependencies (4)

- [varint](https://npm.io/package/varint.md) ^5.0.0
- [pull-reader](https://npm.io/package/pull-reader.md) ^1.3.1
- [safe-buffer](https://npm.io/package/safe-buffer.md) ^5.1.2
- [pull-pushable](https://npm.io/package/pull-pushable.md) ^2.2.0

## Alternatives

- [byte-size](https://npm.io/package/byte-size.md) — 2.1M weekly downloads
- [speed-limiter](https://npm.io/package/speed-limiter.md) — 16.0K weekly downloads
- [@powersync/node](https://npm.io/package/@powersync/node.md) — 10.9K weekly downloads
- [@ledgerhq/coin-cardano](https://npm.io/package/@ledgerhq/coin-cardano.md) — 1.0K weekly downloads
- [@jayesol/jayeson.lib.streamfinder](https://npm.io/package/@jayesol/jayeson.lib.streamfinder.md) — 1.0K weekly downloads

## Recent versions

- 1.3.3 (latest) — 2019-05-03
- 1.3.2 — 2019-04-04
- 1.3.1 — 2018-07-13
- 1.3.0 — 2017-05-28
- 1.2.1 — 2017-04-11
- 1.2.0 — 2016-09-05
- 1.1.0 — 2016-09-01
- 1.0.0 — 2016-06-13

## README

# pull-length-prefixed

[![](https://img.shields.io/badge/made%20by-Protocol%20Labs-blue.svg?style=flat-square)](http://ipn.io)
[![](https://img.shields.io/badge/project-IPFS-blue.svg?style=flat-square)](http://ipfs.io/)
[![](https://img.shields.io/badge/freenode-%23ipfs-blue.svg?style=flat-square)](http://webchat.freenode.net/?channels=%23ipfs)
[![Coverage Status](https://coveralls.io/repos/github/dignifiedquire/pull-length-prefixed/badge.svg?branch=master)](https://coveralls.io/github/dignifiedquire/pull-length-prefixed?branch=master)
[![Travis CI](https://travis-ci.org/dignifiedquire/pull-length-prefixed.svg?branch=master)](https://travis-ci.org/dignifiedquire/pull-length-prefixed)
[![Circle CI](https://circleci.com/gh/dignifiedquire/pull-length-prefixed.svg?style=svg)](https://circleci.com/gh/dignifiedquire/pull-length-prefixed)
[![Dependency Status](https://david-dm.org/dignifiedquire/pull-length-prefixed.svg?style=flat-square)](https://david-dm.org/dignifiedquire/pull-length-prefixed) [![js-standard-style](https://img.shields.io/badge/code%20style-standard-brightgreen.svg?style=flat-square)](https://github.com/feross/standard)
[![standard-readme compliant](https://img.shields.io/badge/standard--readme-OK-green.svg?style=flat-square)](https://github.com/RichardLitt/standard-readme)

> Streaming length prefixed buffers with pull-streams

## Table of Contents

- [Installation](#installation)
- [Usage](#usage)
- [Contribute](#contribute)
- [License](#license)

## Installation

```bash
$ npm install --save pull-length-prefixed
```

## Usage

```js
var pull = require('pull-stream')
var lp = require('pull-length-prefixed')

// encode
pull(
  pull.values([Buffer.from('hello world')]),
  lp.encode(),
  pull.collect(function (err, encoded) {
    if (err) throw err
    console.log(encoded)
    // => [Buffer <0b 68 65 6c 6c 6f 20 77 6f 72 6c 64>]
  })
)

// decode
pull(
  pull.values(encoded), // e.g. from above
  lp.decode(),
  pull.collect(function (err, decoded) {
    if (err) throw err
    console.log(decoded)
    // => [Buffer <68 65 6c 6c 6f 20 77 6f 72 6c 64>]
  })
)
```

## API

### `encode([opts])`

- `opts: Object`, optional
  - `fixed: false`: If true uses a fixed 4 byte Int32BE prefix instead of varint

By default all messages will be prefixed with a varint. If you want to use a fixed length prefix you can specify this through the `opts`.

Returns a pull-stream through.

### `decode([opts])`

- `opts: Object`, optional
  - `fixed: false`: If true uses a fixed 4 byte Int32BE prefix instead of varint
  - `maxLength`: If provided, will not decode messages longer than the size specified, if omitted will use the current default of 4MB.

By default all messages will be prefixed with a varint. If you want to use a fixed length prefix you can specify this through the `opts`.


Returns a pull-stream through.

### `decodeFromReader(reader, [opts], cb)`

- `reader: [pull-reader](https://github.com/dominictarr/pull-reader)`
- `opts: Object`, optional. Same as for `decode`.
- `cb: Function`: Callback called with `(err, message)`.

This uses a [pull-reader](https://github.com/dominictarr/pull-reader) instance to reade and decode a single message. Useful when using [pull-handshake](https://github.com/pull-stream/pull-handshake) with length prefixed messages.


## Contribute

PRs and issues gladly accepted! Check out the [issues](//github.com/dignifiedquire/pull-length-prefixed/issues).

## License

MIT © 2016 Friedel Ziegelmayer

---
_Source: https://npm.io/package/pull-length-prefixed · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._