Flask Python Full Tutorial – Creating a Login Authentication system

In this tutorial, we will be using Flask, a lightweight web application framework written in Python, to create a login authentication system. This system will allow users to register, login, and logout of the web application.

Setting up Flask

First, you will need to install Flask. You can do this by running the following command in your terminal:

pip install Flask

Next, create a new Python file and import the necessary Flask modules:


from flask import Flask, render_template, request, redirect, url_for, session


Creating the Login Page

Now, let’s create the login page. You can use HTML and Jinja templating to create the form for users to enter their username and password. Here is an example:


<form method="POST" action="{{ url_for('login') }}">
<label for="username">Username:</label>
<input type="text" id="username" name="username"><br>
<label for="password">Password:</label>
<input type="password" id="password" name="password"><br>
<input type="submit" value="Login">
</form>


Implementing the Login Authentication System

Now, let’s implement the login authentication system in Flask. Here is an example of how you can authenticate users:


app = Flask(__name__)
app.secret_key = 'supersecretkey'

@app.route('/')
def index():
return render_template('login.html')

@app.route('/login', methods=['POST'])
def login():
username = request.form['username']
password = request.form['password']

if username == 'admin' and password == 'password':
return 'Login successful'
else:
return 'Login failed'

if __name__ == '__main__':
app.run(debug=True)


Conclusion

Congratulations! You have now created a basic login authentication system using Flask in Python. You can further enhance this system by adding features such as user registration, password hashing, and session management. Happy coding!