@keyv/compress-gzip

Gzip compression for Keyv

Gzip compression for Keyv.

Table of Contents

• Install
• Usage
• API
  • @keyv/compress-gzip([options])
    • options
• Migrating to v6
• License

Install

npm install --save keyv @keyv/compress-gzip

Usage

import Keyv from 'keyv';
import KeyvGzip from '@keyv/compress-gzip';

const keyv = new Keyv({store: new Map(), compression: new KeyvGzip()});

API

@keyv/compress-gzip([options])

options

Options are pako v3 options, such as level, windowBits or dictionary. The same object is passed to pako's deflate in compress and to its inflate in decompress.

const keyv = new Keyv({ compression: new KeyvGzip({ level: 9 }) });

Migrating to v6

• KeyvGzip implements the v6 KeyvCompressionAdapter interface: compress(value: string): Promise<string> and decompress(value: string): Promise<string>. Keyv passes it the whole serialized entry, and compress returns a base64 string.
• The v5 serialize and deserialize methods, the public opts property and the per-call options argument of compress and decompress were removed. Pass options to the constructor instead.
• pako was upgraded from v2 to v3. The v2 to: 'string' option is no longer used; decompress always returns a string.
• Values that Keyv v5 wrote with @keyv/compress-gzip can't be read by v6. v5 compressed only the value field inside the JSON envelope, so reading an old entry fails with incorrect header check. Keyv emits error, and get returns undefined when an error listener is attached or rejects when none is. Treat a compressed store as a cache that v6 repopulates, or read the old entries with v5 and write them again with v6. See the v5 to v6 migration guide.
• Compression needs serialization, which is on by default. With serialization: false, Keyv stores values without compressing them.

License

MIT © Jared Wray