Edit Model data using ModelForm: ModelForm validation error - django

Question

I am working on my first django app. I am building an app that allows the user to rate beer. I want my user to be able to edit an entry they've already created. I take them to a ModelForm, and ask for their entry. When the POST method is called, my data is invalid. Here is my model.py:
from django.db import models
class Rating(models.Model):
beer_name = models.TextField()
score = models.DecimalField(max_digits=2, decimal_places=1)
notes = models.TextField(blank=True)
brewer = models.TextField(blank=True)
and forms.py:
from django import forms
from ratings.models import Rating
class RatingForm(forms.ModelForm):
class Meta:
model = Rating
fields = ['beer_name', 'score', 'notes', 'brewer']
Here is the views.py of my edit function:
def edit(request, row_id):
rating = get_object_or_404(Rating, pk=row_id)
if request.method == "POST":
form = RatingForm(request.POST, instance=rating)
if form.is_valid():
form.save()
return redirect(home)
else:
return HttpResponse("Invalid entry.")
else:
context = {'form': rating}
form = RatingForm(instance=rating)
return render(
request,
'ratings/entry_def.html',
context
)
However, every time the POST is called I get an "Invalid entry." HttpResponse, meaning my form.is_valid() is being returned False. Here is my template:
{% extends "base.html" %}
{% block content %}
<div class="container-fluid">
<div class="row">
<div class="col-sm-10 col-sm-offset-1">
<h2>Edit Rating</h2>
<form role="form" method="post">
{% csrf_token %}
<p>Beer Name: <textarea>{{ form.beer_name }}</textarea></p>
<p>Score: <input type="text" name="BeerScore" value="{{ form.score }}"></p>
<p>Notes: <textarea>{{ form.notes }}</textarea></p>
<p>Brewer: <textarea>{{ form.brewer }}</textarea></p>
<p><button type="submit" class="save btn btn-primary">Save</button></p>
<p><button type="reset" class="btn btn-primary">Cancel</button></p>
</form>
</div>
</div>
</div>
{% endblock %}
So when I press my Save button, I am getting the response. Here is my edit url in urls.py:
urlpatterns = [
...
url(r'rating/edit/(?P<row_id>[0-9]+)/$', edit , name='rating-edit'),
]

Answer 1

You're wrapping fields in other fields which don't have name attributes. This is most likely causing the values to be excluded from the request.POST data.
Additionally, Django form fields all have a corresponding HTML widget. So there's really no need to render the HTML by hand, unless you need to.
Change your template code to:
<p>
{{ form.beer_name.label }}: {{ form.beer_name }}
{% if form.beer_name.errors %}
<br />{{ form.beer_name.errors }}
{% endif %}{# repeat for other fields as needed #}
</p>
<p>{{ form.score.label }}: {{ form.score }}</p>
<p>{{ form.notes.label }}: {{ form.notes }}</p>
<p>{{ form.brewer.label }}: {{ form.brewer }}</p>
<p><button type="submit" class="save btn btn-primary">Save</button></p>
<p><button type="reset" class="btn btn-primary">Cancel</button></p>
If you need to change the widget, do so at the form class level:
class RatingForm(forms.ModelForm):
class Meta:
model = Rating
def __init__(self, *args, **kwargs):
super(RatingForm, self).__init__(*args, **kwargs)
self.fields['notes'].widget = forms.Textarea()
This way, Django manages the attributes and binding for you.
Your view can also use some cleanup:
def edit(request, row_id):
rating = get_object_or_404(Rating, pk=row_id)
form = RatingForm(request.POST or None, instance=rating)
if request.method == "POST" and form.is_valid():
form.save()
return redirect(home)
context = {'form': rating}
return render(request, 'ratings/entry_def.html', context)