Creating First Flask App
Step-by-Step: Create Your First Flask App
1. Install Flask
Make sure Flask is installed:
pip install flask2. Create the Project Structure
/flask_app
├── app.py
├── /templates
│ └── index.html3. Write Your Flask App
app.py
from flask import Flask, render_template
# Initialize the Flask app
app = Flask(__name__)
# Create a route
@app.route('/')
def home():
return render_template('index.html')
# Run the app
if __name__ == '__main__':
app.run(debug=True)4. Create an HTML Template
templates/index.html
<!DOCTYPE html>
<html>
<head>
<title>My First Flask App</title>
</head>
<body>
<h1>Hello, Flask!</h1>
<p>Welcome to your first web app using Python Flask.</p>
</body>
</html>5. Run the Flask App
Open your terminal and navigate to the folder, then run:
python app.pyYou'll see output like:
Running on http://127.0.0.1:5000/
6. View in Your Browser
Open your browser and go to: http://127.0.0.1:5000/
You will see:
Hello, Flask! Welcome to your first web app using Python Flask.
Bonus: Add Another Page
Update app.py:
@app.route('/about')
def about():
return '<h2>This is the About Page</h2>'Visit: http://127.0.0.1:5000/about
Done!
You've now created a fully functional, simple Flask web app!