Node.js+Express.js |正在尝试设置HTTPS服务器

我正在尝试使用Node.js和Express.js设置HTTPS服务器。

我目前正在尝试:

const filesystem = require('fs');
const express = require('express');
const server = express();
const http = require('http').Server(server);
const https = require('https');
const io = require('socket.io')(http);
require('./routes')(server);
require('./chat-logic')(io);

// Dummy cert
const privateKey  = filesystem.readFileSync('cert/key.pem', 'utf8');
const certificate = filesystem.readFileSync('cert/cert.pem', 'utf8');

const credentials = {key: privateKey, cert: certificate};
const httpsServer = https.createServer(credentials, server);

server.use(express.static(__dirname + '/src'));
http.listen(3000, () => console.log('Listening on *3000'));
httpsServer.listen(3443, () => console.log('HTTPS on *3443'));

但是,我得到了这个错误:

_tls_common.js:134
      c.context.setKey(key, passphrase);
                ^

Error: error:06065064:digital envelope routines:EVP_DecryptFinal_ex:bad decrypt

我做错了什么?