nodejs mongodb 存储文件

以下是基于nodejs express mongodb multer实现的文件上传、存储、分页、管理功能的示例代码：

1.安装依赖

npm install express multer mongodb

2.引入依赖

const express = require('express');
const multer = require('multer');
const MongoClient = require('mongodb').MongoClient;
const ObjectId = require('mongodb').ObjectId;
const url = 'mongodb://localhost:27017';
const dbName = 'fileUpload';
const upload = multer({ dest: 'uploads/' });
const app = express();

3.连接数据库

MongoClient.connect(url, { useNewUrlParser: true }, function(err, client) {
  if (err) throw err;
  console.log("Connected successfully to server");
  const db = client.db(dbName);
  // ...
});

4.上传文件

app.post('/upload', upload.single('file'), function(req, res, next) {
  const file = req.file;
  const collection = db.collection('files');
  collection.insertOne(file, function(err, result) {
    if (err) throw err;
    res.send('File uploaded successfully!');
  });
});

5.获取文件列表

app.get('/files', function(req, res, next) {
  const collection = db.collection('files');
  const pageNum = parseInt(req.query.pageNum) || 1;
  const pageSize = parseInt(req.query.pageSize) || 10;
  const skip = (pageNum - 1) * pageSize;
  collection.find().skip(skip).limit(pageSize).toArray(function(err, docs) {
    if (err) throw err;
    res.send(docs);
  });
});

6.删除文件

app.delete('/files/:id', function(req, res, next) {
  const collection = db.collection('files');
  const id = req.params.id;
  collection.deleteOne({ _id: ObjectId(id) }, function(err, result) {
    if (err) throw err;
    res.send('File deleted successfully!');
  });
});