Login Page In Flask

As a developer, creating a login page is an essential task when building a web application. This page serves as the entry point for users to access the application and also plays a crucial role in safeguarding sensitive data. In this article, I will discuss creating a login page in Flask, a robust Python web framework.

Setting Up Flask

Before we start building the login page, let’s make sure we have Flask installed. Open your terminal and enter the following command:

pip install flask

Once Flask is installed, we can start setting up our Flask application. Create a new file called app.py and import the necessary modules:

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

Next, let’s initialize our Flask app:

app = Flask(__name__)

Creating the Login Form

Now that we have our Flask app set up, let’s create the login form. In Flask, we can use Flask-WTF, an extension that integrates Flask with WTForms, to easily build forms.

First, let’s install Flask-WTF:

pip install flask-wtf

Now, import the necessary modules and create a new file called forms.py:

from flask_wtf import FlaskForm
from wtforms import StringField, PasswordField, SubmitField
from wtforms.validators import DataRequired

In forms.py, we can define our login form:

class LoginForm(FlaskForm):
    username = StringField('Username', validators=[DataRequired()])
    password = PasswordField('Password', validators=[DataRequired()])
    submit = SubmitField('Login')

Now that we have our form defined, let’s go back to app.py to create the login route.

Creating the Login Route

In app.py, we can create the login route to handle the form submission:

@app.route('/login', methods=['GET', 'POST'])
def login():
    form = LoginForm()
    if form.validate_on_submit():
        # Check if the username and password are valid
        # Redirect to the home page if valid
        return redirect(url_for('home'))
    return render_template('login.html', title='Login', form=form)

The login.html template will contain the HTML code for our login page. Let’s create a new folder called templates and add a file called login.html:

{% extends 'base.html' %}
{% block content %}
    

Login


    


        


            
            
        


        


            
            
        


        


            
        


    


{% endblock %}

Conclusion

Building a login page in Flask is essential for any web application that requires user authentication. By following this tutorial, we have learned how to set up Flask, create a login form using Flask-WTF, and handle the form submission in the login route. With this knowledge, you can now add a secure login functionality to your Flask applications.

Remember, the login page is just the beginning of user authentication. Make sure to implement additional security measures, such as password hashing and session management, to protect your users’ information.

Now that you have learned how to create a login page in Flask, go ahead and start implementing it in your own projects. Happy coding!