为什么我会收到 Django NoReverseMatch 错误？

Question

I am trying to send an activation email to users when signing up, but I keep getting a NoReverseMatch error when trying to render the URL in the template.

The error I get is:

Reverse for 'user_activation' with keyword arguments '{'uidb64': 'MiC', 'token': 'aeue9g-3a31bdff969c41c0bb1d3775a1fa98ac'}' not found. 1 pattern(s) tried: ['account/activate/(?P<uidb64>[0-9A-Za-z_\\-]+)/(?P<token>[0-9A-Za-z]{1,13}-[0-9A-Za-z]{1,20})/$']

urls.py

from .views import *
from django.urls import re_path

urlpatterns = [
    re_path(r'^activate/(?P<uidb64>[0-9A-Za-z_\-]+)/(?P<token>[0-9A-Za-z]{1,13}-[0-9A-Za-z]{1,20})/$', user_activation_view, name='user_activation'), # user activation view
]

template.txt

{% autoescape off %}
To activate your account ({{ user.email }}), please click the link below:

{{ protocol }}://{{ domain }}{% url 'user_activation' uidb64=uid token=token %}

If clicking the link above doesn't work, you can copy and paste the URL in a new browser
window instead.

If you did not make this request, please ignore this email.
{% endautoescape %}

Answer 1

The pattern for the token variable is:

<token>[0-9A-Za-z]{1,13}-[0-9A-Za-z]{1,20}

THis thus means that there are two sequence of [0-9A-Za-z] characters: one with one to thirteen characters, and one with one to twenty characters, and these are separated by a hyphen.

Your token however has:

'aeue9g-3a31bdff969c41c0bb1d3775a1fa98ac'
\__ __/ \_____________ ________________/
   v                  v
 6 chars           32 chars

So this does not match the specifications. If you want to accept this token, you can alter the pattern, for example to:

<token>[0-9A-Za-z]{1,13}-[0-9A-Za-z]{1,}