POST to view not updating database-CodePudding

I have a view that I want to be able to add an event to a project. There are 2 models, one for the Project and one for Event.

Project Model

class Project(models.Model):

    project_name = models.CharField(max_length=50, blank=False, unique=True)
    project_website = models.URLField(max_length=50, blank=True)
    project_description = models.TextField(blank=True)
    ckeditor_classic = models.TextField(blank=True)
    project_category = models.CharField(max_length=15, blank=True)
    project_type = models.CharField(max_length=10, blank=True)
    project_platform = models.CharField(max_length=25, blank=True)
    project_marketcap = models.IntegerField(blank=True, null=True)
    project_stage = models.CharField(max_length=25, blank=True)
    project_blockchain = models.CharField(max_length=25, blank=True)
    project_investors = models.ManyToManyField(Investor, blank=True)
    project_developers = models.ManyToManyField(Developer, blank=True)


    def __str__(self):
        return str(self.project_name)

Event Model

class Event(models.Model):

    project = models.ForeignKey(Project, to_field='project_name', on_delete=models.CASCADE)
    event_name = models.CharField(max_length=100)
    event_date = models.DateTimeField(blank=True)
    event_url = models.URLField(max_length=100, blank=True)

    def __str__(self):
        return str(self.event_name)

The event has a ForeignKey to the Project.

when I go to the project page for a specific project, I then click a button to enable me to create an event.

The Project Name is pre-populated using this URL

path('apps/add_event/<int:project_id>', view=AddEvent, name="add_event"),

This creates a simple form that i can then assign a name and date for the event, but when i POST (Submit) the data doesn't get added to the database.

I do get a POST in the logs [25/Nov/2021 21:37:11] "POST /apps/add_event/3 HTTP/1.1" 302 0

I can't work out why the data is not being updated in the database?

Form.PY

class addEventForm(forms.ModelForm):
    def __init__(self, *args, **kwargs):
        super(addEventForm, self).__init__(*args, **kwargs)

    class Meta:
        model = Event
        fields = '__all__'

View.py

@login_required
def AddEvent(request,project_id):
    project = Project.objects.get(pk=project_id)
    form = addEventForm(request.POST or None, instance=project)
    if form.is_valid():
        form.save()
        return redirect('http://127.0.0.1:8000/')
    
    return render(request, 'pages/add_event.html', {'project': project, "form": form})

I'm wondering if its this line form = addEventForm(request.POST or None, instance=project) should the instance be instance=event

I added in event = Event.objects.all() and changed the instance=event but it throws an error:

AttributeError at /apps/add_event/4
'QuerySet' object has no attribute '_meta'

So I am at a bit of a loss. Any ideas?

CodePudding user response：

You can not make project the instance: your form works on an Event. By using instance=project you let the form edit attributes that belong to the event like event_name, but these will not be saved to the database, since a Project has no column event_name.

The view thus should take request.POST as data, and we set the .project of the Event wrapped in the form with:

from django.shortcuts import get_object_or_404

@login_required
def AddEvent(request,project_id):
    project = get_object_or_404(Project, pk=project_id)
    if request.method == 'POST':
        form = addEventForm(request.POST)
        if form.is_valid():
            form.instance.project = project
            form.save()
            return redirect('http://127.0.0.1:8000/')
    else:
        form = addEventForm()
    return render(request, 'pages/add_event.html', {'project': project, "form": form})