http-encoding
v2.0.1
Published
Everything you need to handle HTTP message body content-encoding
Downloads
263,406
Maintainers
Readme
http-encoding
![Available on NPM](https://img.shields.io/npm/v/http-encoding.svg)
Part of HTTP Toolkit: powerful tools for building, testing & debugging HTTP(S)
Everything you need to handle HTTP message body content-encoding
This package includes methods to decode & encode all commonly used HTTP content encodings, in a consistent format, usable in both Node.js and browsers.
The supported codecs are:
- Gzip
- Raw deflate (with or without a zlib wrapper)
- Brotli
- Zstandard
- Base64
All encoding names are case-insensitive (although lowercase is generally standard). The 'identity', 'amz-1.0', 'none', 'text', 'binary', 'utf8' and 'utf-8' encodings are all supported as no-op encodings, passed through with no en/decoding at all. Only 'identity' is standard, but the others are all in common use regardless.
Found a codec used in real-world HTTP that isn't supported? Open an issue!
API
The library includes two general methods:
decodeBuffer(body, encoding)
Takes an encoded body buffer and encoding (in the format of a standard HTTP content-encoding header) and returns a promise for a decoded buffer, using the zero to many buffers specified in the header.
The input buffer can be any Uint8Array including a Node Buffer (a subclass of Uint8Array). A node-compatible buffer is always returned.
If any encoding is unrecognized or unavailable then this method will throw an exception.
A decodeBufferSync
method is also available for some use cases, but not recommended, as it's less performant and cannot support some encodings (Brotli or Zstandard).
encodeBuffer(body, encoding, { level })
Takes a raw body buffer and a single encoding (a valid HTTP content-encoding name) and returns a promise for an encoded buffer, using the zero to many buffers specified in the header.
The input buffer can be any Uint8Array (including a Node Buffer, which is a Uint8Array subclass) or an ArrayBuffer. A node-compatible buffer is always returned.
If any encoding is unrecognized or unavailable then this method will throw an exception.
Per-codec methods
This library also exports consistent async methods to compress and decompress each of the codecs directly:
gzip
gunzip
deflate
inflate
inflateRaw
brotliCompress
brotliDecompress
zstdCompress
zstdDecompress
encodeBase64
decodeBase64
Each method accepts a buffer and returns a promise for a buffer.
Browser usage
To use this in a browser, you'll need to use a bundler (e.g. Webpack) that can include standard Node.js polyfill packages, you may need to install those polyfill packages, and your bundler needs to support bundling WebAssembly (e.g. Webpack v4+).
In Webpack v4 this should all work automatically. In Webpack v5 this will require explicit dependencies and configuration. See this package's own test webpack config and dev dependencies for a working example.
Brotli and Zstandard are only supported in runtime environments that support WebAssembly. All WebAssembly packages are loaded on-demand and only when native methods (e.g. Node's zlib.brotli*
) are not available.