Question 194716 in Html Question posted in
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Html – Connecting Express server and mariadb

I am trying to make a very simple login webpage, no security or anything like that. My system right now consists of an OpenSuse server with a mariadb database and an Express server and an HTML file for the client.

Express server:

const mariadb = require('mariadb');
const express = require('express');
const session = require("express-session");
const http = require('http');

const app = express();

app.use(session({
  secret: 'secret',
  resave: true,
  saveUninitialized: true
}));
app.use(express.json());
app.use(express.urlencoded({
  extended: true
}));
const expresServer = http.createServer(app);

var connection = mariadb.createPool({
  host: "localhost",
  user: "user",
  password: "pass",
  database: "users",
  connectionLimit: 2
});

app.use(express.static(__dirname + '/client'))
app.get("/", (req, res) => {
  res.sendFile(__dirname + '/client/login.html')
})

app.post('/auth', function(request, response) {
  // Capture the input fields
  let username = request.body.username;
  let password = request.body.password;
  // Ensure the input fields exists and are not empty
  if (username && password) {
    // Execute SQL query that'll select the account from the database based on the specified username and password
    connection.query('SELECT * FROM USERS WHERE User = ? AND Pass = ?', [username, password], function(error, results, fields) {
      // If there is an issue with the query, output the error
      if (error) throw error;
      // If the account exists
      if (results.length > 0) {
        // Authenticate the user
        request.session.loggedin = true;
        request.session.username = username;
        // Redirect to home page
        response.redirect('/main');
      } else {
        response.send('Incorrect Username and/or Password!');
      }
      response.end();
    });
  } else {
    response.send('Please enter Username and Password!');
    response.end();
  }
});

app.get('/main', function(request, response) {
  // If the user is loggedin
  if (request.session.loggedin) {
    // Output username
    response.send('Welcome back, ' + request.session.username + '!');
  } else {
    // Not logged in
    response.send('Please login to view this page!');
  }
  response.end();
});

expresServer.listen(3000, () => {
  console.log("Listening on 3000");
})

HTML login:

<!DOCTYPE html>
<html lang="es">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width,initial-scale=1">
  <title>UAV5G</title>
  <link rel="shortcut icon" href="/imgs/Logo.png" />
  <link rel="stylesheet" href="css/login.css" media="screen" />
  <link rel="stylesheet" href="css/all.min.css" />
</head>

<body>
  <div class="elem-box">
    <div class="login-box">
      <h2>Login</h2>
      <form action="/auth" method="post">
        <div class="user-box">
          <input type="text" name="username" id="username" required>
          <label for="username">Username</label>
        </div>
        <div class="user-box">
          <input type="password" name="password" id="password" required>
          <label for="password">Password</label>
        </div>
        <input class="login" type="submit" value="Login">
      </form>
    </div>
    <img src="/imgs/Logo.png" class="logo">
  </div>
</body>

</html>

I do not think CSS is needed.

The problem here is that the Express server throws this error:

/home/node/Server/node_modules/mariadb/lib/misc/errors.js:61
  return new SqlError(msg, sql, fatal, info, sqlState, errno, additionalStack, addHeader);
         ^

SqlError: (conn=-1, no: 45028, SQLState: HY000) retrieve connection from pool timeout after 10010ms
    (pool connections: active=0 idle=0 limit=2)
    at module.exports.createError (/home/node/Server/node_modules/mariadb/lib/misc/errors.js:61:10)
    at Pool._requestTimeoutHandler (/home/node/Server/node_modules/mariadb/lib/pool.js:344:26)
    at listOnTimeout (node:internal/timers:569:17)
    at process.processTimers (node:internal/timers:512:7) {
  sqlMessage: 'retrieve connection from pool timeout after 10010msn' +
    '    (pool connections: active=0 idle=0 limit=2)',
  sql: null,
  fatal: false,
  errno: 45028,
  sqlState: 'HY000',
  code: 'ER_GET_CONNECTION_TIMEOUT'
}

I do not know why, I can connect to the database from console using that username and password and adding connectTimeout: 10000 (or higher) does not help.

Tags:

2

Answers


  1. 0

    I think you must have to release the connection after you get your data. Might be causing all the troubles for you.

    connection.query('SELECT * FROM USERS WHERE User = ? ...', function (error, results, fields) {

// When done with the connection, release it.
connection.release();
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  2. 0

    There is an error using mariadb connector:
    there is 2 different implementation : promise and callback.

    • promise : const mariadb = require('mariadb');
    • callback : const mariadb = require('mariadb/callback');

    problem here is that you use promise implementation then call a callback method:

    connection.query('SELECT * FROM USERS WHERE User = ? AND Pass = ?', [username, password], function(error, results, fields) {

    so either you change that to promise, or use callback implementation

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