Backend MySQL

PHOTO

Wed May 03 2023 19:43:05 GMT+0000 (Coordinated Universal Time)

const express = require("express");
const mysql = require("mysql2");
const cors = require("cors");

const bodyParser = require("body-parser");
const cookieParser = require("cookie-parser");
const session = require("express-session");

const bcrypt = require('bcrypt');
const saltRound = 10;
 
const app = express();
 
app.use(express.json());
app.use(
    cors({
        origin: ["http://localhost:3000"],
        methods: ["GET", "POST"],
        credentials: true,
    })
);
app.use(cookieParser());
app.use(bodyParser.urlencoded({ extended: true }));
app.use (
    session ({
        key: "userId",
        secret: "subscribe",
        resave: false,
        saveUninitialized: false,
        cookie: {
            expires: 60 * 60 * 24,
        },
    })
);
const db = mysql.createConnection({
    user: "username",
    host: "localhost",
    password: "PASSWORD-MYSQL",
    database: "usuarios",
});
 
app.post('/register', (req, res)=> {
    const username = req.body.username;
    const password = req.body.password;
    bcrypt.hash(password,saltRound, (err, hash) => {
    if (err) {
            console.log(err)
    }
   
    let insertQuery = 'INSERT INTO ?? (??,??) VALUES (?,?)';
    let query = mysql.format(insertQuery, ["usuarios", "username", "password", username, hash]);
    db.query(query, function(err, response,fields) {
        if (err) {
            console.log("Error: ");
            console.error(err);
        }
        // rows added
        console.log("Response: ");
        console.log(response);
        if  (response.affectedRows==1){
            res.send("OK");
        } else {
            res.send("NO");
        }
    });
    })
});
app.get("/login", (req, res) => {
  if (req.session.user) {
    res.send({ loggedIn: true, user: req.session.user });
  } else {
    res.send({ loggedIn: false });
  }
});
app.post('/login', (req, res) => {
 const username = req.body.username;
 const password = req.body.password;
 
 db.execute(
        "SELECT * FROM usuarios WHERE username = ?;",
        [username], 
        (err, result)=> {
            if (err) {
                res.send({err: err});
            }
            if (result.length > 0) {
                bcrypt.compare(password, result[0].password, (error, response) => {
                    if (response) {
                        req.session.user = result;
                        console.log(req.session.user[0].username);
                        if (req.session.user[0].username === username) {
                            res.send("OK");
                        } else {
                            res.send("NO");
                        }
                    } else{
                        res.send({message: "Wrong username/ password comination!"}); 
                    }
                });
            } else {
                res.send({ message: "User doesn't exists"});
            }
        }
    );
});
 
app.listen(3001, () => {
    console.log("running server");
});

COPY

Save snippets that work from anywhere online with our extensions

Comments

App

@luisjdominguezp

Home.js App.js Create react app Backend MySQL

#html #javascript #nodejs

How to Save HTML Form Data in JSON - Express

<form action="/new" method="post">
 
  <input name="title" type="text">
  <input name="description" type="text">
  <button type="submit">Submit Form</button>
 
</form>

> More steps

#javascript #nodejs #commandline

HTTPS Redirect in Nodejs

npm install heroku-ssl-redirect

> More steps

#javascript #nodejs

Save to MongoDB without Duplicates Using Mongoose

var mongoose = require('mongoose');
var Schema = mongoose.Schema;

const exampleSchema = new Schema({
    title: { type: String , required: true},
    content: [{type: String}]
});


var Example = mongoose.model('Example', exampleSchema);
module.exports = Example;

> More steps

#nodejs

Express Post Request to Edit Post

router.post('/:id/edit', auth.requireLogin, (req, res, next) => {
  Post.findByIdAndUpdate(req.params.id, req.body, function(err, post) {
    if(err) { console.error(err) };

     res.redirect(`/`+req.params.id);
  });
});

#nodejs

Memcached Cloud session store with express-session to preserve sessions off-server

var express = require("express");
var app = express();
const session = require('express-session');
var MemcachedStore = require('connect-memjs')(session);

// configure sessions
var store = new MemcachedStore({servers: [process.env.MEMCACHEDCLOUD_SERVERS], username: process.env.MEMCACHEDCLOUD_USERNAME, password: process.env.MEMCACHEDCLOUD_PASSWORD});
app.use(session({ secret: 'keyboard cat',
   resave: true,
   saveUninitialized: true,
   cookie: { secure: true }, 
   store: store
}))

#javascript #nodejs

Slugify a Field in Mongoose Schema

var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var slug = require('mongoose-slug-generator');

mongoose.plugin(slug);

const pageSchema = new Schema({
    title: { type: String , required: true},
    slug: { type: String, slug: "title" }
});

var Page = mongoose.model('Page', pageSchema);
module.exports = Page;

#javascript #nodejs #handlebars #express

Pagination Helper for Handlebars - Node.js Express

https://gist.github.com/trantorLiu/5924389

#sql #nodejs

javascript - Import sql file in node.js and execute against PostgreSQL - Stack Overflow

function processSQLFile(fileName) {

  // Extract SQL queries from files. Assumes no ';' in the fileNames
  var queries = fs.readFileSync(fileName).toString()
    .replace(/(\r\n|\n|\r)/gm," ") // remove newlines
    .replace(/\s+/g, ' ') // excess white space
    .split(";") // split into all statements
    .map(Function.prototype.call, String.prototype.trim)
    .filter(function(el) {return el.length != 0}); // remove any empty ones

  // Execute each SQL query sequentially
  queries.forEach(function(query) {
    batch.push(function(done) {
      if (query.indexOf("COPY") === 0) { // COPY - needs special treatment
        var regexp = /COPY\ (.*)\ FROM\ (.*)\ DELIMITERS/gmi;
        var matches = regexp.exec(query);
        var table = matches[1];
        var fileName = matches[2];
        var copyString = "COPY " + table + " FROM STDIN DELIMITERS ',' CSV HEADER";
        var stream = client.copyFrom(copyString);
        stream.on('close', function () {
          done();
        });
        var csvFile = __dirname + '/' + fileName;
        var str = fs.readFileSync(csvFile);
        stream.write(str);
        stream.end();
      } else { // Other queries don't need special treatment
        client.query(query, function(result) {
          done();
        });
      }
    });
  });
}

#bcrypt #authentication #express #nodejs #password

Async function for bcrypt.compare()

const comparePassword = async (password, hash) => {
    try {
        // Compare password
        return await bcrypt.compare(password, hash);
    } catch (error) {
        console.log(error);
    }

    // Return false if error
    return false;
};

//use case
(async () => {
    // Hash fetched from DB
    const hash = `$2b$10$5ysgXZUJi7MkJWhEhFcZTObGe18G1G.0rnXkewEtXq6ebVx1qpjYW`;

    // Check if password is correct
    const isValidPass = await comparePassword('123456', hash);

    // Print validation status
    console.log(`Password is ${!isValidPass ? 'not' : ''} valid!`);
    // => Password is valid!
})();

#nodejs #mongoose #mongodb

Split the customerName into firstName..the fisrt letter..the first index

db.customers.updateMany({},
  [{ $set : { m : {$arrayElemAt:[{ $split: ["$customerName", " "] },0]}} }],

);

#heroku #seed #nodejs

Seed db after deploying app to Heroku

# Open the terminal in the app dyno in Heroku

heroku run bash

 

# We may then run the seed file

node bin/seed.js

#javascript #nodejs

Search inside an array

const songs[];
const results;

for (var i, i++, i<songs.length){
    if(song[i].artist == "Drake"){
      result.push(songs[i]);
    };

// OR

const songs [];
const result = songs.filter ( song => song.artist == "Drake");

#javascript #nodejs

AJAX Call for a HTTP POST request without refreshing the page

$.ajax({
  type: "POST",
  url: url,
  data: data,
  success: function (result) {
       alert("The result is "+result);
	}
});

#nodejs

Set up Cookies with express-session

                                var app = express()
var sess = {
  secret: 'keyboard cat',
  cookie: {}
}
 
if (app.get('env') === 'production') {
  app.set('trust proxy', 1) // trust first proxy
  sess.cookie.secure = true // serve secure cookies
}
 
app.use(session(sess))

#javascript #nodejs

Querying SQL Server in Node.js Using Async/Await - JavaScript in Plain English

https://medium.com/javascript-in-plain-english/querying-sql-server-in-node-js-using-async-await-5cb68acf2144

Backend MySQL

Save snippets that work from anywhere online with our extensions

Comments

More like this

App

Browse more snippets >>

Backend MySQL

Save snippets that work from anywhere online with our extensions

Comments

More like this

App

Browse more snippets >>

Embed code snippet