serverAuth.js

const fs = require("fs");
const bodyParser = require("body-parser");
const jsonServer = require("json-server");
const jwt = require("jsonwebtoken");

const server = jsonServer.create();
const router = jsonServer.router("./database.json");
const userdb = JSON.parse(fs.readFileSync("./user.json", "UTF-8"));

server.use(jsonServer.defaults());

const SECRET_KEY = "123456789";

const expiresIn = "1h";

// Create a token from a payload
function createToken(payload) {
  return jwt.sign(payload, SECRET_KEY, { expiresIn });
}

// Verify the token
function verifyToken(token) {
  return jwt.verify(
    token,
    SECRET_KEY,
    (err, decode) => (decode !== undefined ? decode : err)
  );
}

// Check if the user exists in database
function isAuthenticated({ email, password }) {
  return (
    userdb.users.findIndex(
      user => user.email === email && user.password === password
    ) !== -1
  );
}

server.post("/auth/login", (req, res) => {
  const { email, password } = req.body;
  if (isAuthenticated({ email, password }) === false) {
    const status = 401;
    const message = "Incorrect email or password";
    res.status(status).json({ status, message });
    return;
  }
  const access_token = createToken({ email, password });
  res.status(200).json({ access_token });
});

server.use(/^(?!\/auth).*$/, (req, res, next) => {
  if (
    req.headers.authorization === undefined ||
    req.headers.authorization.split(" ")[0] !== "Bearer"
  ) {
    const status = 401;
    const message = "Error in authorization format";
    res.status(status).json({ status, message });
    return;
  }
  try {
    verifyToken(req.headers.authorization.split(" ")[1]);
    next();
  } catch (err) {
    const status = 401;
    const message = "Error access_token is revoked";
    res.status(status).json({ status, message });
  }
});

server.use(router);

server.listen(3000, () => {
  console.log("Run Auth API Server");
});