- Published on
Understanding Flask's Application Instance
- Authors
- Name
- hwahyeon
app = Flask(__name__)
app = Flask(__name__)
is the code used to create a Flask application instance. In this code, the __name__
variable holds the name of the currently running file or module.
- When the file is executed directly (e.g.,
python example.py
),__name__
is assigned the value"__main__"
. - When the file is imported as a module (e.g.,
import example
),__name__
is assigned the module's name (e.g.,"example"
).
An application instance represents the Flask application itself.
- This object interacts with WSGI (Web Server Gateway Interface) to handle incoming requests and generate appropriate responses.
- Developers use the application instance to define routes, configure settings, and register extensions.
- When the Flask application runs, the application instance manages all interactions between the server and the request-response cycle.
In short, the application instance serves as the "central control hub" of a Flask application and plays a critical role in the request-response lifecycle.