- 验证码图片 / Token
- 登录 / 登出
- 增 / 删 / 改 / 查
- 上传 / 下载
- 跨域 / CORS / 代理
const express = require('express')
const app = express() // 创建实例
const router = express.Router() // 创建路由
app.use('/', router) // 装载路由// http
http.createServer(app).listen(3002)
// https
const pem = selfsigned.generate()
https.createServer({ key: pem.private, cert: pem.cert }, app).listen(3003)app.use(express.static(path.join(__dirname, 'public')))
// 或者
app.use('/static', express.static(path.join(__dirname, 'public')))// 'Content-Type': 'application/json'
app.use(express.json())
// 'Content-Type': 'application/x-www-form-urlencoded'
app.use(express.urlencoded({ extended: false }))// /search?id=&userId=
router.get('/search', (req, res) => {
const { id, userId } = req.query
if (id) {
const item = todos.find(v => v.id === +id)
return res.json({ query: req.query, data: item })
}
let items = todos
if (userId) {
items = items.filter(v => v.userId === +userId)
}
res.json({ query: req.query, data: items })
})
// /query/:id
router.get('/query/:id(\\d{0,})', (req, res) => {
const { id } = req.params
if (id) {
const item = todos.find(v => v.id === +id)
return res.json({ query: req.params, data: item })
}
res.json({ query: req.params, data: todos })
})// 查询 /search ({ id?, userId? })
router.post('/search', (req, res) => {
const { id, userId } = req.body // app.use(express.json())
if (id) {
const item = todos.find(v => v.id === id)
return res.json({ query: req.body, data: item })
}
let items = todos
if (userId) {
items = items.filter(v => v.userId === userId)
}
res.json({ query: req.body, data: items })
})
// 新增 /add ({ id?, userId, title? })
router.post('/add', (req, res) => {
const { id, userId, title } = req.body // app.use(express.json())
if (!userId) {
return res.send('新增失败，userId 为空')
}
if (!todos.some(v => v.userId === userId)) {
return res.send(`新增失败，userId: ${userId} 不存在`)
}
if (id) {
if (todos.some(v => v.id === id)) {
return res.send(`新增失败，id: ${id} 已经存在`)
}
todos.push({ id, userId, title })
} else {
todos.push({id: getNextId(), userId, title })
}
res.json({ query: req.body, data: todos })
})
// 修改 /update ({ id, userId, title? })
router.post('/update', (req, res) => {
const { id, userId, title } = req.body // app.use(express.json())
if (id) {
const item = todos.find(v => v.id === id)
if (!item) {
return res.json(`更新失败，id：${id} 不存在`))
}
item.title = title
return res.json({ query: req.body, data: todos })
}
if (!userId) {
return res.json(`更新失败，缺少更新条件 id 或 userId`))
}
const items = todos.filter(v => v.userId === userId)
if (!items.length) {
return res.json(`更新失败，没有满足条件的数据`))
}
items.forEach(v => (v.title = title))
res.json({ query: req.body, data: todos })
})
// 删除 /del/:id
router.post('/del/:id(\\d+)', (req, res) => {
const { id } = req.params
const index = todos.findIndex(v => v.id === +id)
if (~index) {
todos.splice(index, 1)
return res.json({ query: req.params, data: todos })
}
res.send(`删除失败，id：${id} 不存在`)
})// 获取图片（验证码）
router.get('/verifyCode', (req, res) => {
// req.cookies <= app.use(require('cookie-parser')())
if (!req.cookies[tokenName]) {
res.cookie(tokenName, 'Test-Token', { httpOnly: true, maxAge })
}
// 根据文件扩展名自动设置'Content-Type'
res.sendFile('verifyCode.jpg', { root: join(__dirname, '../public') })
})<img src="/verifyCode" alt="验证码" /><!-- 查看 -->
<a href="/verifyCode" download="test.jpg">下载图片</a>const download = (req, res) => {
// 以“附件”的形式传输文件，自动设置'Content-Disposition'和'Content-Type'
// => res.attachment(filePath).sendFile(filePath)
res.download(join(__dirname, '../public/verifyCode.jpg'), 'verifyCode.jpg')
}
// POST 和 GET 方式都可以下载
router.route('/download').post(download).get(download)<form action="/download" method="POST">
<button type="submit">form POST /download</button>
</form><button type="button" onclick="download()">fetch POST /download</button>
<script>
function download() {
fetch('/download', { method: 'POST' })
.then(res => res.blob())
.then(blob => {
const url = URL.createObjectURL(blob)
const event = new MouseEvent('click')
const a = document.createElement('a')
a.href = url
a.download = 'test.jpg'
a.dispatchEvent(event)
URL.revokeObjectURL(url)
})
}
</script><a href="/download/backend"> <a> /download </a><input type="file" name="avatar" />const multer = require('multer')
const upload = multer().single('avatar')
router.post('/single', upload, (req, res) => {
res.json({ query: req.body, file: { ...req.file, buffer: '...' } })
})<input type="file" name="avatars" multiple />const upload = multer().array('avatars')
router.post('/multiple', upload, (req, res) => {
res.json({
query: req.body,
files: req.files.map(f => ({ ...f, buffer: '...' }))
})
})const upload = multer().fields([{ name: 'avatar' }, { name: 'avatars' }])
router.post('/fields', upload, (req, res) => {
res.json({
query: req.body,
files: Object.keys(req.files).reduce(
(o, k) => ({
...o,
[k]: req.files[k].map(f => ({ ...f, buffer: '...' }))
}),
{}
)
})
})<input type="file" name="avatar" accept=".png, .jpg, .jpeg" />const check = multer({
limits: { fileSize: 1048576 }, // 文件大小上限 1MB
fileFilter(req, file, cb) {
if (!['image/jpeg', 'image/png'].includes(file.mimetype)) {
return cb(new Error('文件格式不正确'))
}
cb(null, true)
}
}).single('avatar')
router.post(
'/singlecheck',
(req, res, next) => {
check(req, res, err => {
// 自定义错误处理
if (err instanceof multer.MulterError) {
err.code === 'LIMIT_FILE_SIZE'
? res.send('文件太大')
: next(err)
} else if (err) {
res.send(err.message)
} else {
next()
}
})
},
(req, res) => {
res.json({
query: req.body,
file: { ...req.file, buffer: '...' }
})
}
)