Question

I’ve been working with a simple model and was having some trouble saving the ModelForm data. I want to allow users to create and edit existing “Group” objects in the database. If the user chooses to “Edit” an existing group, i want the resulting form to be pre-populated with that objects existing data. Then, if they click on “Save”, it should update any changed data. The model and view I’m using is below. The problem I’m having is that form.is_valid() never returns True. What am i doing wrong here?

MODEL

class Analyst(models.Model):
    def __unicode__(self):
        return unicode("%s, %s"%(self.last, self.first))
    id = models.AutoField(primary_key=True)
    first = models.CharField(max_length=32)
    last = models.CharField(max_length=32)

class Alias(models.Model):
    def __unicode__(self):
        return unicode(self.alias)
    alias = models.CharField(max_length=32)

class Octet(models.Model):
    def __unicode__(self):
        return unicode(self.num)
    num = models.IntegerField(max_length=3)

class Group(models.Model):
    def __unicode__(self):
        return unicode(self.name)
    name = models.CharField(max_length=32, unique=True) #name of the group
    id = models.AutoField(primary_key=True) #primary key
    octets = models.ManyToManyField(Octet, blank=True) #not required
    aliases = models.ManyToManyField(Alias, blank=True) #not required
    analyst = models.ForeignKey(Analyst) #analyst assigned to group, required

VIEW

class GroupEditForm(ModelForm):
    class Meta:
        model = Group

def index(request):
    if request.method == 'GET':
        groups = Group.objects.all().order_by('name')
        return render_to_response('groups.html', 
                                  { 'groups': groups, }, 
                                  context_instance = RequestContext(request),
                                  )

def edit(request):
    if request.method == "POST": #a group was selected and the submit button clicked on the index page
        form = GroupEditForm(instance = Group.objects.get(name=request.POST['name'])) #create a form and pre-populate existing data for that object
    elif request.method == "GET": #the "add new" button was clicked from the index page
        form = GroupEditForm() #create a new form with no data pre-populated

    return render_to_response('group_edit.html',
                             { 'form': form,  },
                             context_instance = RequestContext(request),
                             )

def save(request):
    if request.method == "POST":
        form = GroupEditForm(request.POST)
        if form.is_valid():
            form.save()
            return HttpResponseRedirect('/groups/')

and the relevant template

Template

<h1>Edit Group Information</h1>
<form method="post" action="/groups/edit/save/">{% csrf_token %}
<div class="edit">
<br></br>
{{form}}
</div>
<br></br>
<input type="submit" value="Save"> 
<a href="/groups/"><input type="button" name="cancel" value="Cancel" /></a>
</form>

Answer 1

Try using the django-debug-toolbar. Attach it to your project and you’ll be able to see what is being set through on your form, perhaps why it’s not passing validation. It’s very easy to get up and running so give it a try.