如何从 multer.array 函数验证多个文件的 mimetype？

Question

我已经为此工作了几个小时，但仍然想不出解决方案！我的原始代码是检查使用 multer 上传的单个图像的 mimetype，它运行良好，但我无法将此代码应用于多个图像。我不确定我是否以正确的方式处理这个问题，可能需要想出一种新方法。请看下面的代码：

Multer 中间件

const multerOptions = {
    storage: multer.memoryStorage(),
    fileFilter(req, file, next) {
        const isPhoto = file.mimetype.startsWith('image/');
        if(isPhoto) {
            next(null, true);
        } else {
            next({ message: 'That filetype isn\'t allowed!'}, false);
        }
    }
};

独创的单图倍增功能

exports.upload = multer(multerOptions).single('photo');

exports.resize = async (req, res, next) => {
    // check if there is no new file to resize
    if (!req.file) {
        next(); // skip to the next middleware
        return;
    } 
    const extension = req.file.mimetype.split('/')[1];
    req.body.photo = `${uuid.v4()}.${extension}`;
    // resize the image
    const photo = await jimp.read(req.file.buffer);
    await photo.resize(800, jimp.AUTO);
    await photo.write(`./public/uploads/${req.body.photo}`);
    next();
};

新的多图多图功能

exports.upload = multer(multerOptions).array('photo',[5]);

exports.resize = async (req, res, next) => {
    // check if there is no new file to resize
    if (!req.files) {
        next(); // skip to the next middleware
        return;
    } 
    imageArray = req.files;
    const extensions = [];
    for (var i = 0; i < imageArray.length; i++) {
        imageArray[i].mimetype.split('/')[1].push(extensions);
    }
    // I HAVEN'T MADE IT PAST THIS LINE YET AND AM STILL STUCK ABOVE
    req.body.photo = `${uuid.v4()}.${extension}`;
    // resize the image
    const photo = await jimp.read(req.files.buffer);
    await photo.resize(800, jimp.AUTO);
    await photo.write(`./public/uploads/${req.body.photo}`);
    next();
};

Answer 1

很难确切地知道哪里出了问题，但是通过使用 async await，您不能简单地将您的单个工作示例包装在一个 for 循环中吗？例如：

imageArray = req.files;
for (var i = 0; i < imageArray.length; i++) {
  const file = imageArray[i]
  const extension = file.mimetype.split('/')[1]
  const name = `${uuid.v4()}.${extension}`
  // resize the image
  const photo = await jimp.read(file.buffer)
  await photo.resize(800, jimp.AUTO)
  await photo.write(`./public/uploads/${name}`)
}
next()

这实际上就是您在工作的单个示例中所拥有的，但是包含在一个循环中。

如何从 multer.array 函数验证多个文件的 mimetype？

How to verify the mimetype of multiple files from a multer.array function?

javascript

multer