certificate.txt

openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout cert.key -out cert.pem -config req.cnf -sha256

https_express_server.js

const httpStatusCodes = require('http-status-codes');
const express = require('express');
const request = require('request');
const config = require('./config');
const helmet = require('helmet');
const https = require('https');
const app = express();
const fs = require('fs');

const key = fs.readFileSync('./security/cert.key', 'utf-8'); 
const cert = fs.readFileSync('./security/cert.pem', 'utf-8');

const credentials = { key, cert };

app.use(helmet());

app.get('/getPdfDocument', (req, res) => {
  const uri = req.query.uri;
  if (uri) {
    request({ 
      uri, 
      method: 'GET',
      encoding: null
    }, (err, response, body) => {
      if (err) {
        res.status(httpStatusCodes.INTERNAL_SERVER_ERROR).send({ message: 'Unable to get the file' });
      } else {
        res.set(response.headers);
        res.send(body);
      }
    });
  } else {
    res.status(httpStatusCodes.BAD_REQUEST)
      .send({ error: 'uri query parameter is missing' });
  }
});

https.createServer(credentials, app).listen(config.PORT, () => console.log('server listening on port', config.PORT));

req.cnf

[req]
distinguished_name = req_distinguished_name
x509_extensions = v3_req
prompt = no
[req_distinguished_name]
C = Country initials like US, RO, GE
ST = State
L = Location
O = Organization Name
OU = Organizational Unit 
CN = www.localhost.com
[v3_req]
keyUsage = critical, digitalSignature, keyAgreement
extendedKeyUsage = serverAuth
subjectAltName = @alt_names
[alt_names]
DNS.1 = www.localhost.com
DNS.2 = localhost.com
DNS.3 = localhost