live-data-sync

Persist and restore the application state. Designed for web-redux

Features

• Support nested array and object
• Only store incremental update (instead of full snapshot)
• Backed by sqlite in sync mode (which is faster than async mode)
• 100% test coverage
• Using append-only log, with on-demand compaction

Usage Example

Create a better-sqlite3 DBInstance

1import { newDB } from 'better-sqlite3-schema'
2
3let db = newDB({
4  path: 'state.db',
5  migrate: false,
6})

Create a persistent Dict

A dict can contains multiple objects. Each object is a "singleton" key-value pair.

1import { Dict } from 'live-data-sync'
2
3let dict = new Dict(db)
4
5// init values if not exists
6dict.init('config', {
7  version: '1.0.0',
8  JWT_SECRET: process.env.JWT_SECRET,
9})
10
11dict.data.version
12// '1.0.0'
13
14// partial update
15dict.update('config', {
16  version: '1.0.1',
17})
18
19dict.data.version
20// '1.0.1'
21
22dict.delete('config')
23dict.data.config
24// {}

For more usage example, refers to dict.spec.ts

Create a persistent Collection

A collection can contains multiple type of objects. Each object is an "instance of" key-value pair sharing similar fields of it's type.

1import { Collection, Int, ObjectDict } from 'live-data-sync'
2
3let collection = new Collection<{
4  users: ObjectDict<{ name: string }>
5  posts: ObjectDict<{ user_id: Int; content: string }>
6}>(db)
7
8let user_id = collection.add('users', { name: 'alice' })
9// 1
10let post_id = collection.add('posts', { user_id, content: 'Hello World' })
11// 2
12
13collection.data.posts[post_id as number].content
14// 'Hello World'
15
16// partial update
17collection.update('posts', post_id, { content: 'Hi' })
18
19collection.data.posts[post_id as number]
20// { user_id: 1, content: 'Hi' }
21
22collection.delete('posts', post_id)
23
24collection.data.posts[post_id as number]
25// undefined

For more usage example, refers to collection.spec.ts

License

This project is licensed with BSD-2-Clause

This is free, libre, and open-source software. It comes down to four essential freedoms [ref]:

• The freedom to run the program as you wish, for any purpose
• The freedom to study how the program works, and change it so it does your computing as you wish
• The freedom to redistribute copies so you can help others
• The freedom to distribute copies of your modified versions to others