Django Models Parent Child Template Rendering

Just a quick little tip.

It took me quite a bit to time to stumble across this, as the Django documentation does not mention it.

If you have a ‘related_name’ set for a ForeignKey field on a model, USE that related_name as the MODELCHILD_SET name when trying to access related objects.

Working Example

Based on the example Polls app in the Writing your first Django app Documentation.

<h1>{{ question.question_text }}</h1>
<ul>
{% for choice in question.choice_set.all %}
    <li>{{ choice.choice_text }}</li>
{% endfor %}
</ul>

If you have in your models, the Choice model in your models.py file.

from django.db import models
class Question(models.Model): 
  question_text = models.CharField(max_length=200) 
  pub_date = models.DateTimeField('date published')
class Choice(models.Model): 
  question = models.ForeignKey(Question,related_name='choices',          on_delete=models.CASCADE) 
  choice_text = models.CharField(max_length=200) 
  votes = models.IntegerField(default=0)

You will need to use that related_name in place of the modelname_set in the template to access the child objects.

Thus, your template would need to look like this otherwise you won’t get any objects from the ForeignKey relation.

<h1>{{ question.question_text }}</h1>
<ul>
{% for choice in question.choices.all %}
    <li>{{ choice.choice_text }}</li>
{% endfor %}
</ul>

I sure hope this helps someone scratching their head and endlessly checking their model names.

Originally published at http://www.dennisbottaro.com on February 11, 2020.