django.urls.exceptions.NoReverseMatch: 'xxx' is not a registered namespace

environment¶

• django== 2.1.1
• Render url in html

xx.html

<a href='{% url 'user:role-role_menu_list' %}'></a>

error message¶

django.urls.exceptions.NoReverseMatch: 'user' is not a registered namespace

Solution¶

The app name is not added to the urls of the app application

app_name = 'user'