JavaScript how to make authorization

Javascript authorization: example and practical guide for quick and easy connection.

Using JavaScript to Make an Authorization System

In order to make a secure authorization system with JavaScript, there are a few steps that need to be taken. First, it is important to create a secure system of authentication by which users can log in and access the application. This can be done by setting up a form with a username and password field, which will be used to check a database of users.

The next step is to create a function that will take the username and password as parameters and compare them to the database. This can be done by using the JavaScript Array.prototype.find() method, which will iterate over the array of users and return the object that matches the given credentials. Here is an example of this function:

function authenticate(username, password) {
  const user = users.find(u => u.username === username && u.password === password);
  if (user) {
    return true;
  }
  return false;
}

Once a user has been authenticated, the application can then set a session cookie to store the user's data and keep them logged into the application. This can be done using the document.cookie property and setting the cookie's expiration date accordingly. Here is an example of this code:

function setCookie(name, value, days) {
  let expires = "";
  if (days) {
    const date = new Date();
    date.setTime(date.getTime() + (days * 24 * 60 * 60 * 1000));
    expires = "; expires=" + date.toUTCString();
  }
  document.cookie = name + "=" + (value || "")  + expires + "; path=/";
}

Finally, the application can set up a function to ensure that the user is logged in and has access to the page. This can be done by checking the session cookie that has been set and ensuring that it matches the user's credentials. This can be done using the JavaScript document.cookie property, which can be used to access the cookie data. Here is an example of the code to do this:

function checkCookie(name) {
  const nameEQ = name + "=";
  const ca = document.cookie.split(';');
  for(let i=0;i < ca.length;i++) {
    let c = ca[i];
    while (c.charAt(0)===' ') c = c.substring(1,c.length);
    if (c.indexOf(nameEQ) === 0) return c.substring(nameEQ.length,c.length);
  }
  return null;
}

By following these steps, it is possible to create a secure authorization system with JavaScript that can be used to protect an application from unauthorized access. This can help ensure that only users who have the correct credentials are able to access the application and its data.