Multer 已经有限制大小属性。此属性仅限制图像。不调整图像大小。我的问题是假设图像大于“限制大小”，如何调整该图像的大小？
var storageOptions = multer.diskStorage({
destination: function (req, file, cb) {
cb(null, 'useravatars/')
},
filename: function (req, file, cb) {
cb(null, file.fieldname + '-' + Date.now())
}
});
var avatarUpload = multer({
storage: storageOptions,
limits: {
fileSize: 1000000
}
}).single("avatar");
【问题讨论】：
标签： node.js
这取决于您是否也想存储调整大小的图像。
无论如何，您都将使用库来处理调整大小操作。 sharp 是一个很好的选择。
在路由处理程序中调整大小（文件存储到磁盘后）：
sharp(req.file).resize(200, 200).toBuffer(function(err, buf) {
if (err) return next(err)
// Do whatever you want with `buf`
})其他选项是创建自己的存储引擎，在这种情况下，您将接收文件数据，调整大小，然后存储到磁盘（复制自 https://github.com/expressjs/multer/blob/master/StorageEngine.md）：
var fs = require('fs')
function getDestination(req, file, cb) {
cb(null, '/dev/null')
}
function MyCustomStorage(opts) {
this.getDestination = (opts.destination || getDestination)
}
MyCustomStorage.prototype._handleFile = function _handleFile(req, file, cb) {
this.getDestination(req, file, function(err, path) {
if (err) return cb(err)
var outStream = fs.createWriteStream(path)
var resizer = sharp().resize(200, 200).png()
file.stream.pipe(resizer).pipe(outStream)
outStream.on('error', cb)
outStream.on('finish', function() {
cb(null, {
path: path,
size: outStream.bytesWritten
})
})
})
}
MyCustomStorage.prototype._removeFile = function _removeFile(req, file, cb) {
fs.unlink(file.path, cb)
}
module.exports = function(opts) {
return new MyCustomStorage(opts)
}【讨论】：
node-gyp rebuild Exit status 1 Failed at the sharp@0.18.4 install script 'node-gyp rebuild' .
试试这个代码Resize Image Upload Using Multer
安装 Express 和 Multer 依赖项
npm install express multer --save
npm install sharp --save
创建 Server.js 文件
const express = require('express');
const multer = require('multer');
const path = require('path');
const sharp = require('sharp');
const fs = require('fs');
const app = express();
const port = 3000
const storage = multer.diskStorage({
destination: function(req, file, cb) {
cb(null, 'uploads/');
},
filename: function(req, file, cb) {
cb(null, file.fieldname + '-' + Date.now() + path.extname(file.originalname));
}
});
var upload = multer({ storage: storage })
app.get('/', (req, res) => {
res.sendFile(__dirname + '/index.html');
});
app.post('/', upload.single('image'),async (req, res) => {
const { filename: image } = req.file;
await sharp(req.file.path)
.resize(200, 200)
.jpeg({ quality: 90 })
.toFile(
path.resolve(req.file.destination,'resized',image)
)
fs.unlinkSync(req.file.path)
res.redirect('/');
});
app.listen(port, () => {
console.log(`Example app listening at http://localhost:${port}`)
})
创建表单
<!DOCTYPE html>
<html lang="en">
<head>
<title>Node JS Resize Image Upload Using Multer Sharp With Example - phpcodingstuff.com</title>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<body>
<h1>Node JS Resize Image Upload Using Multer Sharp With Example - phpcodingstuff.com</h1>
<form action="/" enctype="multipart/form-data" method="post">
<input type="file" name="image" accept='image/*'>
<input type="submit" value="Upload">
</form>
</body>
</html>
享受这个code
【讨论】：
const path = require("path");
const storage = multer.diskStorage({
destination: function (req, file, cb) {
cb(null, path.join(__dirname, "/uploads"));
},
filename: function (req, file, cb) {
cb(null, uuid.v4() + `${path.extname(file.originalname)}`);
}
});
const limits = {
fields: 10,
fileSize: 500 * 1024,
files: 1,
};
const upload = multer({ storage, limits });
const baseUrl = "http://localhost:3000/files/";
router.post("/upload", upload.single("file"), async (ctx, next) => {
ctx.body = {
code: 1,
data: baseUrl + ctx.file.filename,
};
});
【讨论】：