python - Decorating Flask Pluggable Views - BuildError -

i'm trying create site containing navigation bar using flask-menu , flask-breadcrumbs. decorator used (flask-menu example):

@app.route('/') @menu.register_menu(app, '.', 'home') def index():     return tmpl_show_menu() #some view 

however, want use methodview classes allow more complex operations. template excerpt:

{%- item in current_menu.children -%}     <a href="{{ item.url}}">{{ item.text }}</a> {%- endfor -%} 

my code throws builderror: ('contactsapp.siteview', {}, none)

contactsapp = blueprint('contactsapp', __name__, template_folder='templates')  @menu.register_menu(contactsapp, '.', 'list') class listview(methodview):      def get(self):         contacts = contact.objects.all()         return render_template('contacts/list.html', contacts=contacts)  @menu.register_menu(contactsapp, '.site', 'sites') class siteview(methodview):      def get(self):         sites = site.objects.all()         return render_template('contacts/sites.html', sites=sites)  contactsapp.add_url_rule('/', view_func=listview.as_view('list')) contactsapp.add_url_rule('/site/', view_func=siteview.as_view('sites')) 

how can correctly decorate pluggable views? cheers.

there 2 options decorating view:

a. can decorate hand return value of as_view().

def user_required(f):     """checks whether user logged in or raises error 401."""     def decorator(*args, **kwargs):         if not g.user:             abort(401)         return f(*args, **kwargs)     return decorator  view = user_required(userapi.as_view('users')) app.add_url_rule('/users/', view_func=view) 

b. if using flask 0.8+, can specify list of decorators apply in class declaration.

class userapi(methodview):     decorators = [user_required]