How To Set Up And Run Python Flask Apps

Python Flask is a popular web framework for creating web applications quickly and efficiently. In this guide, we will walk you through the steps to set up and run Python Flask apps so you can start building your own web projects.

First, you'll need to have Python installed on your system. You can download the latest version of Python from the official website and follow the installation instructions for your operating system. Once Python is installed, you can proceed to install Flask using the pip package manager.

Open your terminal or command prompt and run the following command to install Flask:

pip install Flask

Flask should now be successfully installed on your system. The next step is to create a Flask app. Start by creating a new directory for your project and navigate to it in the terminal. Inside the project directory, create a new Python file, for example, `app.py`, where you will write your Flask application code.

To create a basic Flask app, you can use the following code snippet as a starting point:

from flask import Flask

app = Flask(__name__)

@app.route('/')
def hello_world():
    return 'Hello, World!'

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

In this code, we are importing the Flask class from the `flask` module and creating a new instance of the Flask class named `app`. We then define a route for the root URL `/` that will return the string 'Hello, World!' when accessed. Finally, we use the `app.run()` method to run the Flask application.

Save the `app.py` file and return to your terminal. Navigate to the directory where your `app.py` file is located and run the following command to start the Flask development server:

python app.py

You should see output similar to the following:

* Running on http://127.0.0.1:5000/ (Press CTRL+C to quit)

Congratulations! You have successfully set up and run a basic Python Flask app. You can now access your Flask app by opening a web browser and entering `http://127.0.0.1:5000/` in the address bar. You should see the 'Hello, World!' message displayed on the page.

To stop the Flask development server, you can press `CTRL + C` in the terminal where the server is running. You can further customize your Flask app by adding more routes, templates, or integrating with databases to create more complex web applications.

In this guide, we've covered the basic steps to set up and run Python Flask apps. By following these steps and experimenting with Flask, you can start building your own web projects and explore the capabilities of this versatile web framework. Get coding and have fun exploring the world of web development with Python and Flask!