114 lines
2.1 KiB
Markdown
114 lines
2.1 KiB
Markdown
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# Examples
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## CLI
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```js
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const low = require('lowdb')
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const FileSync = require('lowdb/adapters/FileSync')
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const adapter = new FileSync('db.json')
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const db = low(adapter)
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db.defaults({ posts: [] })
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.write()
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const result = db.get('posts')
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.push({ name: process.argv[2] })
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.write()
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console.log(result)
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```
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```sh
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$ node cli.js hello
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# [ { title: 'hello' } ]
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```
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## Browser
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```js
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import low from 'lowdb'
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import LocalStorage from 'lowdb/adapters/LocalStorage'
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const adapter = new LocalStorage('db')
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const db = low(adapter)
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db.defaults({ posts: [] })
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.write()
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// Data is automatically saved to localStorage
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db.get('posts')
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.push({ title: 'lowdb' })
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.write()
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```
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## Server
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Please __note__ that if you're developing a local server and don't expect to get concurrent requests, it's often easier to use `file-sync` storage, which is the default.
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But if you need to avoid blocking requests, you can do so by using `file-async` storage.
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```js
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const express = require('express')
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const low = require('lowdb')
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const FileAsync = require('lowdb/adapters/FileAsync')
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// Create server
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const app = express()
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// Routes
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// GET /posts/:id
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app.get('/posts/:id', (req, res) => {
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const post = db.get('posts')
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.find({ id: req.params.id })
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.value()
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res.send(post)
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})
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// POST /posts
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app.post('/posts', (req, res) => {
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db.get('posts')
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.push(req.body)
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.last()
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.assign({ id: Date.now() })
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.write()
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.then(post => res.send(post))
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})
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// Create database instance and start server
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const adapter = new FileAsync('db.json')
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low(adapter)
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.then(db => {
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db.defaults({ posts: [] })
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.write()
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})
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.then(() => {
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app.listen(3000, () => console.log('listening on port 3000')
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})
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```
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## In-memory
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With this adapter, calling `write` will do nothing. One use case for this adapter can be for tests.
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```js
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const fs = require('fs')
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const low = require('low')
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const FileSync = require('low/adapters/FileSync')
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const Memory = require('low/adapters/Memory')
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const db = low(
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process.env.NODE_ENV === 'test'
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? new Memory()
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: new FileSync('db.json')
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)
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db.defaults({ posts: [] })
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.write()
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db.get('posts')
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.push({ title: 'lowdb' })
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.write()
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```
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