如何在multer中检查文件类型

Question

我正在用 React 做一个项目，运行遇到了一个让我难过的问题。

我想在 cloudinary 上上传我的文件，也想检查我的文件类型和 mime 类型，但遇到这个错误这是我的代码

所以这是我的代码，我无法过滤掉文件类型。

如果有人有解决办法，如果你能帮助我就太好了

const multer = require("multer");
const DatauriParser = require("datauri/parser");
const path = require("path");
const fs = require("fs");
const dontenv = require("dotenv");
dontenv.config({ path: "config.env" });

let storage;
let dataUri;
const parser = new DatauriParser();

if (process.env.STORAGE_TYPE == "cloud") {
    storage = multer.memoryStorage();
    dataUri = (req) =>
        parser.format(
            path.extname(req.file.originalname).toString(),
            req.file.buffer
        );
} else {
    dataUri = {};
    storage = multer.diskStorage({
        destination: function (req, file, cb) {
            var directory = process.env.STORAGE;
            if (!fs.existsSync(directory)) {
                fs.mkdirSync(directory);
            }
            cb(null, directory);
        },
        filename: function (req, file, cb) {
            cb(
                null,
                file.fieldname +
                    "-" +
                    Date.now() +
                    "." +
                    file.originalname.split(".")[1]
            );
        },
        fileFilter: function (req, file, cb) {
            checkFileType(file, cb);
        },
  });
  
    function checkFileType(file, cb) {
        // Allowed ext
        const filetypes = /jpeg|jpg|png|gif/;
        // Check ext
        const extname = filetypes.test(         
            path.extname(req.file.originalname).toString()
        );
        // Check mime
        const mimetype = filetypes.test(file.mimetype);

        if (mimetype && extname) {
            return cb(null, true);
        } else {
            cb("Error: Images Only!");
        }
    }

    // to Check File TYpe
}

const multerUploads = multer({ storage: storage }).single("imageUrl");

module.exports = { multerUploads, dataUri };

我不知道为什么会这样，如果有人经历过，我将不胜感激。

Answer 1

首先fileFilter不是diskStorage的key，它是multer本身的key。此外，您已经在 else 中声明了函数。所以使用 multer 检查文件类型应该是这样的：

const multer = require("multer");
const DatauriParser = require("datauri/parser");
const path = require("path");
const fs = require("fs");
const dontenv = require("dotenv");
dontenv.config({ path: "config.env" });

let storage;
let dataUri;
const parser = new DatauriParser();

if (process.env.STORAGE_TYPE == "cloud") {
    storage = multer.memoryStorage();
    dataUri = (req) =>
        parser.format(
            path.extname(req.file.originalname).toString(),
            req.file.buffer
        );
} else {
    dataUri = {};
    storage = multer.diskStorage({
        destination: function (req, file, cb) {
            var directory = process.env.STORAGE;
            if (!fs.existsSync(directory)) {
                fs.mkdirSync(directory);
            }
            cb(null, directory);
        },
        filename: function (req, file, cb) {
            cb(
                null,
                file.fieldname +
                "-" +
                Date.now() +
                "." +
                file.originalname.split(".")[1]
            );
        }
    });
    // to Check File TYpe
}

function checkFileType(file, cb) {
    // Allowed ext
    const filetypes = /jpeg|jpg|png|gif/;
    // Check ext
    const extname = filetypes.test(
        path.extname(file.originalname).toString()
    );
    // Check mime
    const mimetype = filetypes.test(file.mimetype);

    if (mimetype && extname) {
        return cb(null, true);
    } else {
        cb("Error: Images Only!");
    }
}

const multerUploads = multer({
    storage: storage,
    fileFilter: function (req, file, cb) {
        checkFileType(file, cb);
    },
}).single("imageUrl");

module.exports = { multerUploads, dataUri };

如何在multer中检查文件类型

how to check file type in multer

javascript

node.js

cloudinary

reactjs

multer