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);
// })