added login, follow the readme

server.js

@@ -0,0 +1,67 @@
+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('./db.json');
+
+const userdb = JSON.parse(fs.readFileSync('./users.json', 'UTF-8'));
+
+server.use(bodyParser.urlencoded({extended: true}))
+server.use(bodyParser.json())
+//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({phone, password}){
+    return userdb.users.findIndex(user => user.phone === phone && user.password === password) !== -1;
+  }
+
+  server.post('/auth/login', (req, res) => {
+    const {phone, password} = req.body;
+    if (isAuthenticated({phone, password}) === false) {
+      const status = 401;
+      const message = 'Incorrect phone or password';
+      res.status(status).json({status, message});
+      return;
+    }
+    const access_token = createToken({phone, 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 = 'Bad authorization header';
+      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 not valid';
+      res.status(status).json({status, message});
+    }
+  });
+
+  server.use(router);
+
+  server.listen(3000, () => {
+    console.log('Run Auth API Server');
+  })