Implementing user login in PHP

In the field of object-oriented programming, user authentication is an essential feature for many web applications. This tutorial will help you understand the basic concepts of user login in PHP and implement them through a practical exercise. We will expand our previous knowledge and implement a functional registration form that saves and processes passwords securely.

Key insights

• Creation of a registration form with validation
• Hashing of passwords for security
• Adjustments of the login system to use hashes instead of plaintext passwords

Step-by-step guide

At the beginning, it is important that you have a basic structure for your project where you can include the necessary files. Make sure you have access to a database where you can store your user data.

Step 1: Perform logout

Before you start with registration, you should ensure that you are logged out. Click the logout button to sign out.

Step 2: Create registration form

Create a new registration form. You can use a simple HTML form that allows input for email and password. Make sure to set the URL for the form correctly, so that it forwards the data to the corresponding PHP script.

Step 3: Implement email validation

Add validation that checks whether the entered email address is in the correct format. If the email is invalid, an appropriate error message should be displayed.

Step 4: Password handling

Now you need to process the password input. Add a second input for the password to ensure that the user enters their password correctly. If both passwords do not match, display an error message.

Step 5: Agreement to the terms and conditions

Before the registration can be successfully completed, the user must agree to the terms and conditions (T&Cs). Add a checkbox that the user must actively check.

Step 6: Register user

After successful validation, save the user data in the database. You should use a secure hashing algorithm to store the password. Use SHA-512 as the hash algorithm to enhance security.

Step 7: Verification in the database

After registration, verify that the user has actually been created in the database. This verification can be done with an SQL query that counts the number of records with the specified email address.

Step 8: Modification of the login system

Now that the registration works, it is crucial to modify the existing login system to store and process passwords as hashes. Ensure that you also apply the hashing process to the login request.

Step 9: Testing registration and login

Before finishing, test the complete system to ensure that both registration and login work without errors. Check if the returned error messages for incorrect inputs are correct.

Summary – User login with PHP: Step-by-step guide to implementation

In this guide, you learned how to create a simple registration form and implement the associated security aspects. You tested and successfully applied the basics of user registration and authentication in PHP.