In Django, how do I use a list item's String value to get an object's variable's value?

Question

This is assuming that columns is a list containing Strings, each String is representing one of the object o 's variable.

<tbody>
    {% for o in objects %}
    <tr>
        {% for col in columns %}
        <td>{{ o.col }}</td>
        {% endfor %}
    </tr>
    {% endfor %}
</tbody>

Example:

class Dog(models.Model):
    name = models.CharField()
    age = models.IntegerField()
    is_dead = models.BooleanField()

columns = ('name', 'age')

I cannot explicitly enter the object's variable name and must pass it as another list because I am trying to make a 'generic' template. Also, not all variables must be shown to the users.

Answer 1

I'm not familiar enough with django to know if there's something builtin for this, but... you could just define your own version of getattr as a template filter . For some reason (I'm assuming because it's a builtin function), I wasn't able to simply register the builtin as a new template filter. Either way, this is how I've defined my version:

# This is defined in myapp/templatetags/dog_extras.py
from django import template

register = template.Library()

@register.filter
def my_getattr(obj, var):
    return getattr(obj, var)

To use it, you'll use it just like any other two arg template-filter:

{{ o|my_getattr:col }}

Here's a full example (don't forget the "load" directive at the top!):

{% load dog_extras %}

<table>
    <tbody>
        {% for o in objects %}
        <tr>
            {% for col in columns %}
            <td>{{ o|my_getattr:col }}</td>
            {% endfor %}
        </tr>
        {% endfor %}
    </tbody>
</table>

If you've never made custom template-filters before, be sure to read the docs!