How to implement membership functions using Express & MySQL and JWT - javascript

I currently implemented login and membership functions using Express & MySQL.
And I want to add JWT.
I wanted to create an API only through Postman, not on the Web, and I heard that I had to use Passport to search.
And I know there is also Express-generate, but I want to modify my current code.
I am a beginner in Node.js and want a guide.
app.js
var express = require('express');
var http = require('http');
var static = require('serve-static');
var path = require('path');
var bodyParser = require('body-parser');
var cookieParser = require('cookie-parser');
var expressSession = require('express-session');
var expressErrorHandler = require('express-error-handler');
var mysql = require('mysql');
var pool = mysql.createPool({
connectionLimit:10,
host:'localhost',
user:'root',
password:'password',
database:'test',
debug:false
});
var app = express();
app.set('port', 3000);
app.use('/public', static(path.join(__dirname, 'public')));
app.use(bodyParser.urlencoded({extended:false}));
app.use(bodyParser.json());
app.use(cookieParser());
app.use(expressSession({
secret:'my key',
resave: true,
saveUninitialized:true
}));
var router = express.Router();
router.route('/process/login').post(function(req, res) {
console.log('/process/login');
var paramId = req.body.id;
var paramPassword = req.body.password;
console.log('request parameter:' + paramId + paramPassword);
authUser(paramId, paramPassword, function(err, rows) {
if (err) {
console.log('error');
res.writeHead(200, '{"Content-Type":"text/plain; charset=utf-8"}');
res.write('<h1>error</h1>');
red.end();
return;
}
if (rows) {
console.dir(rows);
res.writeHead(200, '{"Content-Type":"text/plain; charset=utf-8"}');
res.write('<h1>user login success</h1>');
res.write('<div><p>user:' + rows[0].id + ' </p></div>');
res.end();
} else {
res.writeHead(200, '{"Content-Type":"text/plain; charset=utf-8"}');
res.write('<h1>user not found</h1>');
res.end();
}
});
});
router.route('/process/adduser').post(function(req, res) {
console.log('/process/adduser');
var paramId = req.body.id;
var paramPassword = req.body.password;
console.log('request parameter' + paramId + paramPassword);
addUser(paramId, paramPassword, function(err, addedUser) {
if (err) {
console.log('error');
res.writeHead(200, '{"Content-Type":"text/plain; charset=utf-8"}');
res.write('<h1>error</h1>');
red.end();
return;
}
if (addedUser) {
console.dir(addedUser);
res.writeHead(200, '{"Content-Type":"text/plain; charset=utf-8"}');
res.write('<h1>user added</h1>');
res.end();
} else {
res.writeHead(200, '{"Content-Type":"text/plain; charset=utf-8"}');
res.write('<h1>user added fail</h1>');
res.end();
}
});
})
app.use('/', router);
var addUser = function(id, password, callback) {
console.log('addUser');
pool.getConnection(function(err, conn) {
if(err) {
if (conn) {
conn.release();
}
callback(err, null);
return;
}
console.log('db threadid' + conn.threadId);
var data = {id:id, password:password};
var exec = conn.query('insert into users set ?', data,
function(err , result) {
conn.release();
console.log('SQL syntax' + exec.sql);
if (err) {
console.log('SQL error;');
callback(err, null);
return;
}
callback(null, result);
});
});
};
var authUser = function(id, password, callback) {
console.log('authUser' + id + password);
pool.getConnection(function(err, conn) {
if (err) {
if (conn) {
conn.release();
}
callback(err, null);
return;
}
console.log('db threadid:'+ conn.threadId);
var tablename = 'users';
var columns = ['id'];
var exec = conn.query('select ?? from ?? where id = ? and password = ?', [columns, tablename, id, password],
function(err, rows) {
conn.release();
console.log('SQL syntax' + exec.sql);
if (err) {
callback(err, null);
return;
}
if (rows.length >0 ) {
console.log('user find');
callback(null, rows);
} else {
console.log('user not found');
callback(null, null);
}
});
});
};
var errorHandler = expressErrorHandler({
static: {
'404' : './public/404.html'
}
});
app.use(expressErrorHandler.httpError(404));
app.use(errorHandler);
var server = http.createServer(app).listen(app.get('port'), function() {
console.log('server start' + app.get('port'));
});

Hi #yori If you want to create an API, first I will recommend parsing your data as JSON objects and thus eliminating all HTML tags in your code.
In order to use JWT for authentication, you will have to install the jsonwebtoken package as part of your project dependencies: https://www.npmjs.com/package/jsonwebtoken
I will recommend following the in-depth instructions in this post as a guide: https://medium.freecodecamp.org/securing-node-js-restful-apis-with-json-web-tokens-9f811a92bb52
For scope though, here is some explanation:
Express can be used to build robust APIs which can be made available for consumption. POSTMAN is a GUI tool that developers use to query APIs. curl commands is the terminal alternative. JWT is a safe way of representating claims transfered between two parties. I see the need to break down these terms to you so that you will understand the need, relevance and difference between each tool.
Following the guide in the article you will have to refactor your code a little bit.

Related

How to merge two files API (Node.js)

I am a node.js and MySQL beginner and I just started setting up and trying out some basic code.
I find these two APIs to practice, one is the API for the CRUD database, and the other is the API for judging user login / registration.I tried to merge the APIs of these two files, and the result was a problem. I think the current problem is the configuration file (conf.js).I plan to write a function and then wrap any file and use it again, so that the configuration files may not conflict, but I don’t know how to start.
These are the two API teaching URLs I practiced
http://www.expertphp.in/article/user-login-and-registration-using-nodejs-and-mysql-with-example
https://www.footmark.info/programming-language/nodejs/nodejs-restful-webapi-mysql/
index.js
var express = require("express");
var bodyParser = require("body-parser");
var app = express();
var authenticateController = require("./controllers/authenticate-controller");
var registerController = require("./controllers/register-controller");
app.use(bodyParser.urlencoded({ extended: true }));
app.use(bodyParser.json());
app.post("/api/register", registerController.register);
app.post("/api/authenticate", authenticateController.authenticate);
app.listen(3000);
app.js
var bodyparser = require("body-parser");
var express = require("express");
var conf = require("./conf");
var functions = require("./functions");
var user = require("./routes/user");
var app = express();
req.body
app.use(bodyparser.urlencoded({ extended: false }));
app.use(bodyparser.json());
//app.use(functions.passwdCrypto);
app.use("/user", user);
app.listen(conf.port, function() {
console.log("app listening on port " + conf.port + "!");
});
authenticate-controller.js
var connection = require('./../conf');
module.exports.authenticate=function(req,res){
var email=req.body.email;
var password=req.body.password;
connection.query('SELECT * FROM user WHERE email = ?',[email], function (error, results, fields) {
if (error) {
res.json({
status:false,
message:'there are some error with query'
})
}else{
if(results.length >0){
if(password==results[0].password){
res.json({
status:true,
message:'successfully authenticated'
})
}else{
res.json({
status:false,
message:"Email and password does not match"
});
}
}
else{
res.json({
status:false,
message:"Email does not exits"
});
}
}
});
}
register-controller.js
var connection = require('../conf');
module.exports.register=function(req,res){
var today = new Date();
var user={
"name":req.body.name,
"email":req.body.email,
"password":req.body.password,
"created_at":today,
"updated_at":today
}
connection.query('INSERT INTO user SET ?',user, function (error, results, fields) {
if (error) {
res.json({
status:false,
message:'there are some error with query'
})
}else{
res.json({
status:true,
data:results,
message:'user registered sucessfully'
})
}
});
}
user.js(models)
var mysql = require("mysql");
var conf = require("../conf");
var connection = mysql.createConnection(conf.db);
var sql = "";
module.exports = {
items: function(req, callback) {
sql = "SELECT * FROM user";
return connection.query(sql, callback);
},
item: function(req, callback) {
sql = mysql.format("SELECT * FROM user WHERE userId = ?", [req.params.id]);
return connection.query(sql, callback);
},
add: function(req, callback) {
sql = mysql.format("INSERT INTO user SET ?", req.body);
return connection.query(sql, callback);
},
delete: function(req, callback) {
sql = mysql.format("DELETE FROM user WHERE userId = ?", [req.params.id]);
return connection.query(sql, callback);
},
put: function(req, callback) {
connection.beginTransaction(function(err) {
if (err) throw err;
sql = mysql.format("DELETE FROM user WHERE userId = ?", [req.params.id]);
connection.query(sql, function(err, results, fields) {
if (results.affectedRows) {
req.body.id = req.params.id;
sql = mysql.format("INSERT INTO user SET ?", req.body);
connection.query(sql, function(err, results, fields) {
if (err) {
connection.rollback(function() {
callback(err, 400);
});
} else {
connection.commit(function(err) {
if (err) callback(err, 400);
callback(err, 200);
});
}
});
} else {
callback(err, 410);
}
});
});
},
patch: function(req, callback) {
sql = mysql.format("UPDATE user SET ? WHERE userId = ?", [req.body, req.params.id]);
return connection.query(sql, callback);
}
};
user.js(routes)
var express = require("express");
var user = require("../models/user");
var router = express.Router();
router
.route("/")
.get(function(req, res) {
user.items(req, function(err, results, fields) {
if (err) {
res.sendStatus(500);
return console.error(err);
}
if (!results.length) {
res.sendStatus(404);
return;
}
res.json(results);
});
})
.post(function(req, res) {
user.add(req, function(err, results, fields) {
if (err) {
res.sendStatus(500);
return console.error(err);
}
res.status(201).json(results.insertId);
});
});
router
.route("/:id")
.get(function(req, res) {
user.item(req, function(err, results, fields) {
if (err) {
res.sendStatus(500);
return console.error(err);
}
if (!results.length) {
res.sendStatus(404);
return;
}
res.json(results);
});
})
.delete(function(req, res) {
user.delete(req, function(err, results, fields) {
if (err) {
res.sendStatus(500);
return console.error(err);
}
if (!results.affectedRows) {
res.sendStatus(410);
return;
}
res.sendStatus(204);
});
})
.put(function(req, res) {
user.put(req, function(err, results) {
if (err) {
res.sendStatus(500);
return console.error(err);
}
if (results === 410) {
res.sendStatus(410);
return;
}
user.item(req, function(err, results, fields) {
res.json(results);
});
});
})
.patch(function(req, res) {
user.patch(req, function(err, results, fields) {
if (err) {
res.sendStatus(500);
return console.error(err);
}
if (!results.affectedRows) {
res.sendStatus(410);
return;
}
req.body.id = req.params.id;
res.json([req.body]);
});
});
module.exports = router;
conf.js
var mysql = require("mysql");
var connection = mysql.createConnection({
host: "localhost",
user: "root",
password: "1234",
database: "farmbot",
});
connection.connect(function(err) {
if (!err) {
console.log("Database is connected");
} else {
console.log("Error while connecting with database");
}
});
module.exports = connection;
/*If I comment out the code below, I can execute the login / register API*/
/*Without commenting out, can only perform CRUD on the database*/
module.exports = {
db: {
host: "localhost",
user: "root",
password: "1234",
database: "farmbot"
},
port: 3000
};
You will have to refactor them properly. You will need only once file to begin with. Why using it twice?
Refactor them in one file instead of listening to them on different ports. Once done, you can show the code to us so that we can fix it further if there's an issue.
Start from index.js and merge app.js with it but a bit carefully. I think doing it by yourself you will learn much from it.

MongoError: topology was destroyed(when finding the documents) and instance pool was destroyed (when inserting documents)

I'm trying to build REST API with Node.js, Express and Mongodb. I'm using mongodb npm package to connect to the database, below is my sever.js file code
var express = require("express");
var app = express();
var bodyParser = require("body-parser");
var port = process.env.PORT || 8080;
var mongo = require("mongodb");
var Server = mongo.Server;
var Db = mongo.Db;
var ObjectID = mongo.ObjectID;
try{
var config = require('./configure.js');
}catch(e){
console.log("configuration file is hidden on github for security");
config = null;
}
var usersCollection = config.usersCollection;
var login = require('./routes/login/index.js');
var signup = require('./routes/signup/index.js');
var Database = new Db(process.env.DBNAME || config.DBNAME , new Server(process.env.DBHOST || config.DBHOST, process.env.DBPORT || config.DBPORT, {'native_parser': true}));
Database.open(function (err, mongoclient) {
if(err){
console.log("Failed to connect to the database. Please Check the connection");
throw err;
}else{
Database.authenticate(process.env.DBUSER || config.DBUSER, process.env.DBPASS || config.DBPASS, function(err, res) {
if (err) {
console.log("Authentication Failed");
throw err;
}else{
console.log("Connected to the database Successfully");
app.use(bodyParser.urlencoded({ extended: true }));
app.use(bodyParser.json());
var users = Database.collection(usersCollection);
login(app,users);
signup(app,users);
Database.close();
}
});
}
});
app.listen(port,function(){
console.log("Server Started Listening to port : "+port);
});
routes/login/index.js
module.exports = function(app,users){
app.route('/login')
.post(function(req,res){
var username = req.body.username;
var password = req.body.password;
var query = {'FirstName':username};
users.find().toArray(function(err,docs){
if(err){
throw err;
}else{
console.log("no err");
if(doc.LastName == password){
res.send({status : true});
}else{
res.send({status : false});
}
}
});
});
}
and routes/signup/index.js
module.exports = function(app,users){
app.route('/signup')
.post(function(req,res){
var doc = { EmpNo:"1",
FirstName:"Andrew",
LastName:"Neil",
Age:"30",
Gender:"Male",
Skill:"MongoDB",
Phone:"408-1234567",
Email:"Andrew.Neil#gmail.com",
Salary:"80000"
};
users.insert(doc,function(err,info){
if(err){
throw err;
}else{
console.log('Successfully inserted ' + JSON.stringify(info));
res.send({result: 'done'});
}
});
});
}
When i'm trying to insert documents in server.js , i'm able to insert them successfully but through routes/signup/index.js i'm getting instance pool was destroyed similarly if i try to find the documents in server.js no error but if i try to do it from routes/login/index.js then i'm getting error as topology was destroyed.
Need help to resolve it.
Those errors are thrown if connection is somehow cut in the middle of the process.
Because both users.find() and users.insert() functions are async your server.js file reaches to the Database.close() function and closes the connection to your database before it finishes the process thus giving the errors.

Middleware getting executed multiple times?

I am trying to make a url shortener app using express. I have 2 middle wares for routes /shorten/:url* and /:code respectively. Somehow when I make requests like /shorten/iamarshad.com (requests that are not formatted and will fail my validateUrl method), middleware handling that request gets executed sometimes twice and sometime thrice. Why is this happening ?
Code for route.js:
var express = require("express");
var router = express.Router();
var crypto = require("./crypto");
var styles = "<style>#import url('https://fonts.googleapis.com/css?family=Cormorant+Garamond');" +
"body{background: #fefefe; word-wrap: break-word;}" +
"p {font-size: 30px;color: #b33c66;font-family: 'Cormorant Garamond', monospace;text-align: center;" +
"margin-top: 40vh;font-weight: 500;word-spacing: 2px;}</style>";
function verifyUrl(req, res, next) {
console.log("/shorten middleware called");
req.params.url += req.params[0];
console.log(req.params.url);
if (validateUrl(req.params.url)) {
req.db.collection("counter")
.find({_id: "counter"})
.toArray(function (err, docs) {
if (err) console.error("Error occurred while getting COUNTER document:", err);
req.encodedId = crypto.encode(docs[0].count);
next();
});
}
else {
var elem = "<p>Please enter correct and formatted url!</p>";
res.send(styles + elem);
}
}
function incrementCounter(req, res, next) {
// increasing counter
req.db.collection("counter")
.update(
{
_id: "counter"
},
{
$inc : {
count : 1
}
}
);
next();
}
function insertUrlDocument(req, res, next) {
//inserting new url document
var obj = {original_url: req.params.url, _id: req.encodedId, entry_time: new Date().toUTCString()};
req.db.collection("urls")
.insert(obj, function(err, data) {
if(err) console.error("Error happened while adding new document:", err);
});
next();
}
function sendResponse(req, res) {
var elem = "<p>" + JSON.stringify({'original_url': req.params.url, 'short_url': 'https://shorten-that.herokuapp.com/' + req.encodedId}) + "</p>";
res.send(styles + elem);
}
function validateUrl(url) {
var format = /(http:\/\/|https:\/\/)[a-z0-9\-]+[.]\w+/;
return (format.test(url));
}
router.get("/:code", function(req, res) {
console.log("/:code middleware called with url", req.params.code);
var code = req.params.code.toString();
// searching short-url-id
req.db.collection("urls")
.find({_id: code})
.toArray(function(err, docs) {
if(err) console.error("Error occurred while searching urls:", err);
console.log(docs);
if(docs.length > 0)
res.redirect(docs[0]["original_url"]);
else {
var elem = "<p>Oops, wrong url requested!</p>";
res.send(styles + elem);
}
});
});
// better solution needed
router.get("/shorten/:url*", [verifyUrl, incrementCounter, insertUrlDocument, sendResponse]);
module.exports = router;
Code for server.js:
var express = require("express")
, mongo = require("mongodb").MongoClient
, port = process.env.PORT || 8080
, path = require("path")
, routes = require("./routes")
, favicon = require("serve-favicon");
var app = express();
app.use(favicon(path.join(__dirname, 'public','favicon.png')));
app.use(express.static(path.join(__dirname, "public")));
var url = 'mongodb://localhost:27017/url-shortener';
mongo.connect(url, function(err, db) {
if (err) console.error("Error occurred while connecting to db:", err);
console.log("successfully connected to db.");
app.use(function(req, res, next) {
req.db = db;
next();
});
app.use("/", routes);
});
app.listen(port, function() {
console.log("App running on", port);
});

in node.js with express req.session is undefined inside my require() module

I'm wondering why req.session.username is undefined in the tag >>>DOESNT WORK<<< while it does work in the tag >>>THIS DOES WORK<<< . I brought in req as an argument to my module but it seems I'm supposed to do something else? The /ajax route is accessed via a ajax call and it does set the session variable in >>>THIS DOES WORK<<<
//index.js file
var express = require('express');
var router = express.Router();
var app = express();
var functions = require('../public/javascripts/functions.js');
router.post('/ajax', function(req, res , next){
var username = req.param("username");
var password = req.param("password");
var operation = req.param("operation");
else if (operation === "validate")
{
async.series([
function()
{
functions.validate(username, password, req);
}
], function(err,result)
{
if (err)
return console.log(err);
console.log(result);
});
//req.session.username = "yaryar"; >>>THIS DOES WORK<<<
}
var strings = ["rad", "bla", "ska"]
console.log('body: ' + JSON.stringify(req.body));
console.log("AJAX RECEIVED");
res.send(strings);
});
module.exports = router;
functions.js file:
module.exports = {
validate: function(username, password, req) {
var url = 'mongodb://localhost';
var MongoClient = require('mongodb').MongoClient;
var assert = require('assert');
var ObjectId = require('mongodb').ObjectID;
MongoClient.connect(url, function(err, db)
{
assert.equal(null, err);
console.log("Connected correctly to server.");
var cursor = db.collection('users').find({username : username});
cursor.each(function(err,doc,req)
{
assert.equal(err, null);
if (doc != null)
{
console.log("user found: " + doc.username);
req.session.username = "ttyy"; // >>>DOESNT WORK<<<
return true
}
else
{
console.log("user not found");
return false;
}
});
//db.close();
});
}
};
you're overwriting req by doing cursor.each(function(err,doc,req) change it to cursor.each(function(err,doc,arr) and it will work

Node js displaying images from server

I am trying to display an image on a basic web page on a localhost w/ port 5000
here is main.js
var http = require('http');
var domain = require('domain');
var root = require('./root');
var image = require('./image');
function replyError(res) {
try {
res.writeHead(500);
res.end('Server error.');
} catch (err) {
console.error('Error sending response with code 500.');
}
};
function replyNotFound(res) {
res.writeHead(404);
res.end('not found');
}
function handleRequest(req, res) {
console.log('Handling request for ' + req.url);
if (req.url === '/') {
root.handle(req, res);
} else if (req.url === '/image.png'){
image.handle(req, res);
} else {
replyNotFound(res);
}
}
var server = http.createServer();
server.on('request', function(req, res) {
var d = domain.create();
d.on('error', function(err) {
console.error(req.url, err.message);
replyError(res);
});
d.run(function() { handleRequest(req, res); });
});
function CallbackToInit(){
server.listen(5000);
};
root.init(CallbackToInit);
Using callbacks I want the server to start listening(5000) only after the init function of the following code runs
var http = require('http');
var body;
exports.handle = function(req, res) {
res.writeHead(200, {
'Content-Type': 'image/png'
});
res.end(body);
};
exports.init = function(cb) {
require('fs').readFile('image.png', function(err, data) {
if (err) throw err;
body = data;
cb();
});
}
It's an assignment I can't use express
I am trying to get image.png to be displayed, I think body = data doesn't work because it can't hold an image like a string? I don't want to put any HTML into my js file.
Don't roll your own app server. Use one of the great web app frameworks like express or connect.
var express = require('express');
var app = express();
app.use(express.logger());
app.use(express.static(__dirname + '/public'));
app.listen(process.env.PORT || 5000);
Trust me, this is better.
Take a look at the node.js example for a simple http server or a tutorial/example, such as this, for serving static files through a simple server.

Categories