必须打开数据库连接才能将文件存储在GridFSStorage._handleFile

时间:2019-01-03 11:23:26

标签: node.js mongodb ng-file-upload

我尝试通过以下Web应用程序在本地MongoDB服务器上上传文件:

const express = require("express");
const bodyParser = require('body-parser');
const path = require('path');
const crypto = require('crypto');
const mongoose = require('mongoose');
const GridFsStorage = require('multer-gridfs-storage');
const Grid = require('gridfs-stream');
const methodOverride = require('method-override');
const multer = require('multer');

const app = express();

// Middleware
app.use(bodyParser.json());
app.use(methodOverride('_method'));
app.set('view engine', 'ejs');

// Mongo URI
const mongoURI =
    'mongodb://localhost:27017/database'

// Create mongo connection
const conn = mongoose.createConnection(mongoURI);

// Init gifs
let gfs;

conn.once('open', () => {
    // Init Stream
    gfs = Grid(conn.db, mongoose.mongo);
    gfs.collection('uploads');
})


// Create storage engine

const storage = new GridFsStorage({
  url: 'mongodb://localhost:27017/database',
  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 });

// @route GET /
// @desc Loads form

app.get('/', (req, res) => {
    res.render('index');
})

// @route POST /upload
//@desc upload file to DB
app.post('/upload', upload.single('file'), (req, res) => {
res.json({ file: req.file });
});

const port = 27017;
  

app.listen(port,()=> console.log('服务器在端口$ {port}上启动));   但出现错误:“必须打开数据库连接才能存储文件       在GridFSStorage._handleFile(/Users/payam/Desktop/mongodb-uploads/node_modules/multer-gridfs-storage/lib/gridfs.js:341:17)       在/Users/payam/Desktop/mongodb-uploads/node_modules/multer/lib/make-middleware.js:144:17       在allowAll(/Users/.../Desktop/mongodb-uploads/node_modules/multer/index.js:8:3)       在wrappedFileFilter(/Users/.../Desktop/mongodb-uploads/node_modules/multer/index.js:44:7)       在Busboy。 (/用户/.../桌面/mongodb-uploads/node_modules/multer/lib/make-middleware.js:114:7)       在Busboy.emit(events.js:182:13)       在Busboy.emit(/Users/.../Desktop/mongodb-uploads/node_modules/busboy/lib/main.js:38:33)       在PartStream。 (/用户/.../桌面/mongodb-uploads/node_modules/busboy/lib/types/multipart.js:213:13)       在PartStream.emit(events.js:182:13)       在HeaderParser中。 (/用户/.../桌面/mongodb-uploads/node_modules/dicer/lib/Dicer.js:51:16)       在HeaderParser.emit(events.js:182:13)       在HeaderParser._finish(/Users/.../Desktop/mongodb-uploads/node_modules/dicer/lib/HeaderParser.js:68:8)       在SBMH。 (/用户/.../桌面/mongodb-uploads/node_modules/dicer/lib/HeaderParser.js:40:12)       在SBMH.emit(events.js:182:13)       在SBMH._sbmh_feed(/Users/.../Desktop/mongodb-uploads/node_modules/streamsearch/lib/sbmh.js:159:14)       在SBMH.push(/Users/.../Desktop/mongodb-uploads/node_modules/streamsearch/lib/sbmh.js:56:14)中”。   任何机构都可以帮助并告诉我我的代码或我的问题是什么   机器?

1 个答案:

答案 0 :(得分:0)

我需要做的就是为Mongo URI设置useNewUrlParser:true:

// Create mongo connection
const conn = mongoose.createConnection(mongoURI, { useNewUrlParser: true });

,对于端口,您可以将其设置为5000,如下所示:

const port = 5000;

app.listen(port, () => console.log(`server started on port ${port}`));