11 2 1 Setting Up Flask Explained

Key Concepts

Setting up Flask involves several key concepts:

• Introduction to Flask
• Installing Flask
• Creating a Basic Flask Application
• Running the Flask Application
• Understanding the Structure of a Flask Application

1. Introduction to Flask

Flask is a lightweight web framework for Python that allows you to build web applications quickly and easily. It is designed to be simple and easy to use, making it a popular choice for beginners and experienced developers alike.

2. Installing Flask

Before you can start building a Flask application, you need to install Flask. You can install Flask using pip, the Python package installer.

pip install Flask
    

3. Creating a Basic Flask Application

A basic Flask application consists of a single Python file. This file contains the code that defines your web application, including routes and views.

Example:

from flask import Flask

app = Flask(__name__)

@app.route('/')
def home():
    return "Hello, Flask!"

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

Analogy: Think of a Flask application as a simple website with a single page that says "Hello, Flask!" when you visit it.

4. Running the Flask Application

Once you have created your Flask application, you can run it by executing the Python file. Flask will start a local web server that you can access in your web browser.

Example:

python app.py
    

Analogy: Running the Flask application is like turning on a light switch to illuminate a room.

5. Understanding the Structure of a Flask Application

A Flask application typically consists of several components, including the main application file, templates, and static files. The main application file contains the core logic, while templates define the HTML structure and static files include CSS, JavaScript, and images.

Example Structure:

my_flask_app/
    app.py
    templates/
        home.html
    static/
        style.css
        script.js
    

Analogy: Think of the structure of a Flask application as a house with different rooms (templates) and decorations (static files) that make it functional and beautiful.