Django form field clean to check if entered date is in a stored range

django, validation

Solution

This should work for you

from django import forms
from models import Dates

class Form(forms.ModelForm):
    fromdate = forms.DateField()
    todate = forms.DateField()

    class Meta:
        model = Dates

    def clean(self):
        form_fromdate = self.cleaned_data.get('fromdate')
        form_todate = self.cleaned_data.get('todate')
        between = Dates.objects.filter(fromdate__gte=form_fromdate, todate__lte=form_todate).exists()
        if between:
            raise forms.ValidationError("Period already between this dates")
        super(Form, self).clean()

EDIT

#views.py
#!/usr/bin/env python
# -*- coding: utf-8 -*-
from django.http import HttpResponse
from django.template import RequestContext
from django.shortcuts import render_to_response

from forms import Form

def index(request, template='index.html'):
    form = Form()
    if request.method == "POST":
        form = Form(request.POST)
        if form.is_valid():
            return HttpResponse(form)

    kwvars = {
        "form": form,
    }
    return render_to_response(template, kwvars, context_instance=RequestContext(request))

#forms.py
from django import forms
from models import Dates

class Form(forms.ModelForm):
    fromdate = forms.DateField()
    todate = forms.DateField()

    class Meta:
        model = Dates

    def clean(self):
        form_fromdate = self.cleaned_data.get('fromdate')
        form_todate = self.cleaned_data.get('todate')
        between = Dates.objects.filter(fromdate__gte=form_fromdate, todate__lte=form_todate).exists()
        if between:
            raise forms.ValidationError("Period already between this date 1")
        super(Form, self).clean()

#index.html
<html>
<head>
</head>
<body>
<form action="" method="POST">
    {% csrf_token %}
    {%  if form.errors %}
        errors: {{ form.errors }}
    {% endif %}
    {{ form }}
    <input type="submit" value="submit">
</form>
</body>
</html>

Problem

I'm trying to write a form clean method to ensure that an entered pair of dates is not currently covered by date ranges stored in the model. So I want to catch `fromdate >= value <= todate` but the `between` filters in my clean methods aren't getting it. Can anyone offer some enlightenment? Models.py ``` class Dates(models.Model): fromdate = models.DateField() todate = models.DateField() ``` Forms.py ``` class Form(forms.Form): fromdate = forms.DateField() todate = forms.DateField() class Meta: model = Dates def clean_fromdate(self): form_fromdate = self.cleaned_data.get('fromdate') exists = Dates.objects.filter(fromdate__contains=form_fromdate).exists() if exists == True: raise forms.ValidationError(_("A period is already entered for this date")) between = Dates.objects.filter(fromdate__gte=form_fromdate, todate__lte=form_fromdate).exists() if between == True: raise forms.ValidationError(_("Period already between this date 1")) return form_fromdate def clean_todate(self): form_todate = self.cleaned_data.get('todate') exists = Dates.objects.filter(todate__contains=form_todate).exists() if exists == True: raise forms.ValidationError(_("A period is already entered for this date")) between = PeriodsOfInactivity2012.objects.filter(fromdate__gte=form_todate, todate__lte=form_todate).exists() if between == True: raise forms.ValidationError(_("Period already between this date 2")) return form_todate ```

Original source