Flask is a web framework for the Python programming language that has gained considerable popularity due to its simplicity and capabilities. The development server provided by Flask allows you to quickly build and test your web applications. One of the attractions of Flask is that it enables you to easily run the server and observe changes in real time.
Among the key features of Flask 3.0, it includes performance improvements and a variety of enhancements. Additionally, this version includes new documentation that simplifies working with extensions and contains more up-to-date practices. That being said, there are many questions regarding how to work with the development server, and we will provide answers to them here.
To get started, it's necessary to ensure that you have Flask installed on your system. This can easily be done using pip. After installation, you can create your own project and run the server. Using the Flask development server allows you to immediately test and observe the results of your code modifications.
After starting the server, you can use Flask's default URL to access your application. Additionally, by using various settings, the possibility of changing the port and server address is also provided. In practice, by using several lines of code, you can create a simple application and work with the development server.
from flask import Flask
app = Flask(__name__)
@app.route('/')
def home():
return 'Hello, welcome to the Flask application!'
if __name__ == '__main__':
app.run(debug=True)
Code Explanation:
Line 1: By using the statement from flask import Flask, we import the Flask class which we need to create our web application.
Line 3: Creating a new instance of the Flask class, we create our web application.
Line 5: By using the decorator @app.route('/') , we define the main route. Here we are specifying that when the user accesses /, the home() function should execute.
Line 6: The home() function returns a welcome message to the user.
Line 8: This condition checks if the script is being run directly. If so, the server will be started in debug mode so that any changes can be observed live.