Function decorator not being invoked

Question

This has been driving me crazy because it should be so simple, but there must be some Python quirk I'm missing. I have a decorator that I'm trying to apply to a Flask route, but for some reason none of the decorators in my views.py seem to be getting loaded. decorators.py ``` def admin_required(func): """Require App Engine admin credentials.""" @wraps(func) def decorated_view(*args, **kwargs): if users.get_current_user(): if not users.is_current_user_admin(): abort(401) # Unauthorized return func(*args, **kwargs) return redirect(users.create_login_url(request.url)) return decorated_view ``` views.py ``` @admin_required @blueprint.route('/') def index(): return render_template('index.html') ``` The `admin_required` decorator function is not being called (index.html is loaded without a redirect), and I cannot figure out why.

Accepted Answer

Short answer: change the order of the decorators; `blueprint.route` only "sees" your undecorated function.

Decorators are applied inside-out, in loose analogy to function calls. Thus your function definition is equivalent to:

```
def index():
    return render_template('index.html')
index = blueprint.route('/')(index)
index = admin_required(index)
```

Note how `blueprint.route` is passed the `index` function before it gets wrapped by `admin_required`. Of course, `admin_required` does eventually get applied to the `index` name in the module, so if you were to call `index` directly, it would go through both decorators. But you're not calling it directly, you're telling flask's request processor to call it.

Function decorator not being invoked

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