我正在使用mongodb地图集将我的数据存储在云中，但是由于不断出现相同的错误，所以我无法存储它错误：必须打开数据库连接才能存储文件
我的服务器端代码
const mongoURI = 'mongodb+srv://caman3874:qwertyuiopaman1234@@amanco-pexfz.mongodb.net/test?retryWrites=true&w=majority';
const conn = mongoose.createConnection(mongoURI,{useNewUrlParser:true});
let gfs;
conn.once('open', () => {
gfs = Grid(conn.db, mongoose.mongo);
gfs.collection('uploads');
console.log("connection made successfully");
});
const storage = new GridFsStorage({
url: mongoURI,
file: (req, file) => {
return new Promise((resolve, reject) => {
crypto.randomBytes(16, (err, buf) => {
if (err) {
return reject(err);
}
const filename = buf.toString('hex') + path.extname(file.originalname);
const fileInfo = {
filename: filename,
bucketName: 'uploads'
};
resolve(fileInfo);
});
});
}
});
const upload = multer({ storage });
app.get('/',(req,res)=>{
res.render('index');
});
app.post('/upload', upload.single('file'), (req, res) => {
res.json({ file: req.file });
});
const port = 5000;
app.listen(port, () => console.log(`Server started on port ${port}`));
我的HTML代码
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm"
crossorigin="anonymous">
</style>
<title>Mongo File Uploads</title>
</head>
<body>
<div class="container">
<div class="row">
<div class="col-md-6 m-auto">
<form action="/upload" method="POST" enctype="multipart/form-data">
<div class="custom-file mb-3">
<input type="file" name="file" id="file" class="custom-file-input">
<label for="file" class="custom-file-label">Choose File</label>
</div>
<input type="submit" value="Submit" class="btn btn-primary btn-block">
</form>
</div>
</div>
</div>
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN"
crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js" integrity="sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q"
crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js" integrity="sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl"
crossorigin="anonymous"></script>
</body>
</html>
错误：必须打开数据库连接才能存储文件在GridFSStorage._handleFile（C：\ Users \ 91807 \ Desktop \ mongo \ node_modules \ multer-gridfs-storage \ lib \ gridfs.js：339：17）在C：\ Users \ 91807 \ Desktop \ mongo \ node_modules \ multer \ lib \ make-middleware.js：144：17在allowAll（C：\ Users \ 91807 \ Desktop \ mongo \ node_modules \ multer \ index.js：8：3）在wrappedFileFilter（C：\ Users \ 91807 \ Desktop \ mongo \ node_modules \ multer \ index.js：44：7）在Busboy。 （C：\ Users \ 91807 \ Desktop \ mongo \ node_modules \ multer \ lib \ make-middleware.js：114：7）在Busboy.emit（events.js：209：13）在Busboy.emit（C：\ Users \ 91807 \ Desktop \ mongo \ node_modules \ busboy \ lib \ main.js：38：33）在PartStream。 （C：\ Users \ 91807 \ Desktop \ mongo \ node_modules \ busboy \ lib \ types \ multipart.js：213：13）在PartStream.emit（events.js：209：13）在HeaderParser中。 （C：\ Users \ 91807 \ Desktop \ mongo \ node_modules \ dicer \ lib \ Dicer.js：51：16）在HeaderParser.emit（events.js：209：13）在HeaderParser._finish（C：\ Users \ 91807 \ Desktop \ mongo \ node_modules \ dicer \ lib \ HeaderParser.js：68：8）在SBMH。 （C：\ Users \ 91807 \ Desktop \ mongo \ node_modules \ dicer \ lib \ HeaderParser.js：40：12）在SBMH.emit（events.js：209：13）在SBMH._sbmh_feed（C：\ Users \ 91807 \ Desktop \ mongo \ node_modules \ streamsearch \ lib \ sbmh.js：159：14）在SBMH.push（C：\ Users \ 91807 \ Desktop \ mongo \ node_modules \ streamsearch \ lib \ sbmh.js：56：14）
const mongoURI = 'mongodb+srv://caman3874:qwertyuiopaman1234@@amanco-pexfz.mongodb.net/test?retryWrites=true&w=majority';
const promise = mongoose.connect(mongoURI, { useNewUrlParser: true });
const conn = mongoose.connection;
let gfs;
conn.once('open',() => {
gfs = Grid(conn, mongoose.mongo);
gfs.collection('uploads');
});
//create storage object
const storage = new GridFsStorage({
db: promise,
file: (req, file) => {
return new Promise((resolve, reject) => {
crypto.randomBytes(16, (err, buf) => {
if (err) {
return reject(err);
}
const filename = buf.toString('hex') + path.extname(file.originalname);
const fileInfo = {
filename: filename,
bucketName: 'uploads'
};
resolve(fileInfo);
});
});
}
});
const upload = multer({ storage });
希望这行得通！