November 3, 2007
Custom django template filter: Sanitize emails
Still working on my Honyaku mailing list archive site, I needed a template filter to sanitize emails. The filter itself was very simple: it was finding out how to write a template filter that took most of my research.
The filter code
Here's the code for the filter. As I said, pretty simple stuff.
"""
A template filter to sanitize emails.
"""
from django import template
register = template.Library()
import re
@register.filter
def sanitize_emails(text):
"""
Sanitize emails in the text.
Blah blah blah ryan@spam.me.com blah blah
=> Blah blah blah ry..@..am.me.com blah blah
"""
text = re.sub(r"(\w\w@\w\w)(\w*?\.)",
r"..@..\2",
text,
re.I | re.M )
# Catch cases like "I.b@foolish.com"
return re.sub(r"(\w@\w\w)(\w*?\.)",
r".@..\2",
text,
re.I | re.M )
Note that despite being known to rail against regular expressions at times, I do believe that they have their uses :).
Where to put the filter
This was the tricky part for me. I eventually found that you put your custom filters in a directory named templatetags, in your application directory. So if your project is myproject, and your app is myapp, the directory structure would look like this:
__init__.py
manage.py
myapp/
__init__.py
models.py
templates/
…
templatetags/
__init__.py
sanitize.py
…
…
Then, in your template, you simply load the filter and use it like so:
<p>{{post.text|escape|sanitize_emails}}</p>
And there you have it. Nice, sanitized emails in your django templates.
