Quiz: How do you handle custom HTTP errors (e.g. 404) in Flask?
The @app.errorhandler() decorator registers view functions to render custom pages when specific HTTP status errors occur.
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The @app.errorhandler() decorator registers view functions to render custom pages when specific HTTP status errors occur.
Functions marked with @app.before_request run prior to view execution, ideal for connection handling or authentication checks.
flash() records lightweight feedback notices (e.g. success messages) retrieved and cleared on subsequent page renders.
Without a secure SECRET_KEY , Flask cannot sign session cookies or validate WTForms CSRF tokens securely.
secure_filename() removes unsafe path characters (e.g. `../`) from user-submitted file names to prevent arbitrary file overwrites.
request.get_json() parses JSON formatted request bodies, returning `None` if content type is invalid.
Depends() allows declaring modular, reusable dependencies (e.g., authentication, DB sessions) injected seamlessly into routes.
FastAPI intelligently infers parameter origins: path variables map to Path , Pydantic models map to Body , and scalar parameters map to …