node链接mongodb数据库的方法详解【阿里云服务器环境ubuntu】

npm i mongodb --save

const http = require('http')  , https = require('https');const express = require('express');const bodyParser = require('body-parser')const app = express();const fs = require('fs');const ejs = require('ejs');const path = require('path');const MongoClient = require('mongodb').MongoClient;// 返回信息const questions = {  code: 200,  msg: 'success',};// https证书，开https服务的自验证证书const options = {  key: fs.readFileSync('./privatekey.pem'),  cert: fs.readFileSync('./certificate.pem')};let xltitle = '标题（初始化数据）',  xlcontent = '内容（初始化数据）',  xlfaceid = '1（初始化数据）';const url = 'mongodb://127.0.0.1/xlbase';// 默认端口27017，无需填写// 也可以修改端口，vim /etc/mongodb.conf// 初始化数据库MongoClient.connect(url, function (err, db) {  if (err) throw err;  let database = db.db('xlbase');  console.log('------------数据库初始化成功------------');// 如果没有face这个集合，会创建一个，所以可以用这个来初始化集合  database.createCollection('face', function (err, res) {    if (err) throw err;    console.log('------------集合初始化完毕------------');    db.close();  });});//设置跨域访问app.all('*', function (req, res, next) {  res.header("Access-Control-Allow-Origin", "*");  res.header("Access-Control-Allow-Headers", "X-Requested-With");  res.header("Access-Control-Allow-Methods", "PUT,POST,GET,DELETE,OPTIONS");  res.header("X-Powered-By", ' 3.2.1');  // res.header("Content-Type", "application/json;charset=utf-8");  next();});// parse application/x-www-form-urlencoded 解析app.use(bodyParser.urlencoded({extended: false}));// parse application/json 解析app.use(bodyParser.json());// view engine setup，视图模版app.set('views', path.join(__dirname, './'));app.set('view engine', 'jade');// 静态资源解析路径（css，js，图片等）app.use(express.static(path.join(__dirname, './static')));// 数据接收接口app.post('/info', function (req, res) {  res.header("Content-Type", "application/json;charset=utf-8");  res.status(200);  xltitle = req.body.title;  xlcontent = req.body.content;  xlfaceid = req.body.faceId;  let info = {    'faceid': xlfaceid,    'title': xltitle,    'content': xlcontent  };  let faceid = {    'faceid': xlfaceid  };  let updateInfo = {$set: info};// 组装更新的信息  MongoClient.connect(url, function (err, db) {    let database = db.db('xlbase');    database.collection('face').find(faceid).toArray(function (err, result) {      if (err) throw err;      // 判断集合中faceid和当前传过来的faceid是否相同和存在      // 如果不存在就新插入这条数据      // 如果存在且相同，就更新数据      if (result.length !== 0 && result[0].faceid === xlfaceid) {        database.collection("face").updateOne(faceid, updateInfo, function (err, res) {          if (err) throw err;          console.log("------------数据更新成功------------");          db.close();        });      } else {        database.collection('face').insertOne(info, function (err, res) {          if (err) throw err;          console.log("------------数据添加成功------------");          db.close();        })      }    })  });  res.json(questions); // 返回信息  res.end(JSON.stringify(req.body, null, 2))});app.get('/index', function (req, res) {  res.status(200);  res.header("Content-Type", "text/html;charset=utf-8");// 根据faceId查询数据  MongoClient.connect(url, function (err, db) {    if (err) throw err;    let dbo = db.db("xlbase");    let face = {"faceid": xlfaceid}; // 查询条件    let xltitle1 = 404;    let xlcontent1 = '网页出错！';    dbo.collection("face").find(face).toArray(function (err, result) {      if (err) throw err;      console.log(result);      xltitle1 = result[0].title;      xlcontent1 = result[0].content;      db.close();      console.log('------------查询完毕------------');      res.send('<h3 style="font-size: 35px">' + xltitle1 + '</h3>' +        '<pre style="white-space: pre-wrap;word-wrap: break-word;font-size: 30px">' + xlcontent1 + '</pre>');      res.end();    });  });})// 配置服务端口// http.createServer(app).listen(3001, function () {//   console.log('3001')// });process.env.NODE_TLS_REJECT_UNAUTHORIZED = "0"; // 绕过证书验证https.createServer(options, app).listen(8009, function () {  console.log('port: 8009');});// var server = app.listen(3001, function () {////   var host = server.address().address;////   var port = server.address().port;////   console.log('Example app listening at http://%s:%s', host, port);// })