How to check (in template) if user belongs to a group

Question

How to check in template whether user belongs to some group?

It is possible in a view which is generating the template but what if I want

Answer 1

In your app create a folder 'templatetags'. In this folder create two files:

__init__.py

auth_extras.py

from django import template
from django.contrib.auth.models import Group 

register = template.Library()

@register.filter(name='has_group')
def has_group(user, group_name): 
    group = Group.objects.get(name=group_name) 
    return True if group in user.groups.all() else False

It should look like this now:

app/
    __init__.py
    models.py
    templatetags/
        __init__.py
        auth_extras.py
    views.py

After adding the templatetags module, you will need to restart your server before you can use the tags or filters in templates.

In your base.html (template) use the following:

{% load auth_extras %}

and to check if the user is in group "moderator":

{% if request.user|has_group:"moderator" %} 
    <p>moderator</p> 
{% endif %}

Documentation: https://docs.djangoproject.com/en/1.11/howto/custom-template-tags/

Answer 2

Watch out that you'll get an exception if the group does not exist in the DB.

The custom template tag should be:

from django import template
from django.contrib.auth.models import Group

register = template.Library()

@register.filter(name='has_group')
def has_group(user, group_name):
    try:
        group =  Group.objects.get(name=group_name)
    except Group.DoesNotExist:
        return False

    return group in user.groups.all()

Your template:

{% if request.user|has_group:"mygroup" %} 
    <p>User belongs to my group 
{% else %}
    <p>User doesn't belong to mygroup</p>
{% endif %}

Answer 3

You need custom template tag:

from django import template

register = template.Library() 

@register.filter(name='has_group') 
def has_group(user, group_name):
    return user.groups.filter(name=group_name).exists() 

In your template:

{% if request.user|has_group:"mygroup" %} 
    <p>User belongs to my group 
{% else %}
    <p>User doesn't belong to mygroup</p>
{% endif %}

Source: http://www.abidibo.net/blog/2014/05/22/check-if-user-belongs-group-django-templates/

Docs: https://docs.djangoproject.com/en/dev/howto/custom-template-tags/