CodeIgniter - Implementing user authentication and authorization

Implementing user authentication and authorization in CodeIgniter involves verifying user identities and controlling access to different parts of your application based on user roles or permissions.  

1. Database Setup:

• Create a database table to store user information, including usernames, passwords, and roles/permissions.
• You can use CodeIgniter's migration feature or manually create the database table.

2. User Model:

• Create a model to handle interactions with the user database table (e.g., User_model).
• Implement methods for user authentication and fetching user information based on credentials.

3. User Authentication:

• Implement a login form where users can enter their credentials (username/email and password).
• Create a controller method to handle the login form submission.
• In the controller method, validate the user's credentials against the database using the User Model.
• If the credentials are valid, create a session for the authenticated user.

4. User Authorization:

• Define roles or permissions for different user types (e.g., admin, user).
• Create middleware or functions to check the user's role/permission before allowing access to certain parts of the application.
• Restrict access to specific controllers or methods based on the user's role/permission.

5. Protecting Routes:

• Use middleware or hooks to protect routes that require authentication or specific roles/permissions.
• Redirect unauthenticated users to the login page or display an error message.

6. Logout:

• Implement a logout functionality where users can log out of their sessions.
• Destroy the session when the user logs out to invalidate the session data.

7. Password Hashing:

• Hash user passwords before storing them in the database to enhance security.
• Use a strong hashing algorithm such as bcrypt to securely hash passwords.

8. Remember Me Functionality:

• Implement a "Remember Me" functionality using cookies to allow users to stay logged in across sessions.
• Use a secure and unique token to identify users and validate their sessions.