I have my model.py file as below. I've created a conjugate primary key date & station.
Models.py
from django.db import models
from django import forms
# Create your models here.
from django.db import models
from django.conf import settings
from django.contrib.auth.models import User
# Create your models here.
class ManHour(models.Model):
class Meta:
unique_together = (('date', 'station'),)
station_choices = (
('KHI','Station1'),
('ISB', 'Station2'),
('LHE','Station3'),
)
station = models.CharField(
max_length=3,
choices=station_choices,
)
date = models.DateField()
date_time = models.DateTimeField(auto_now=True)
imports_airside = models.DecimalField(max_digits= 5, decimal_places= 3, default = 0)
imports_landside = models.DecimalField(max_digits= 5, decimal_places= 3, default = 0)
exports = models.DecimalField(max_digits= 5, decimal_places= 3, default = 0)
Form.py
from django import forms
from manhourapp.models import ManHour
from datetime import date
class DateInput(forms.DateInput):
input_type = 'date'
class InputForm(forms.ModelForm):
class Meta:
model = ManHour
fields = ['date','station', 'imports_airside', 'imports_landside', 'exports']
widgets = {
'date':forms.widgets.DateInput(attrs={'type': 'date', 'max':str(date.today())})
}
Views.py
def form_page(request):
context = {}
try:
man_hour = ManHour.objects.get(pk=request.GET.get("pk"))
except ManHour.DoesNotExist:
man_hour = None
if man_hour:
context["Total_Imports"] = man_hour.imports_airside + man_hour.imports_landside
if man_hour:
context["Total_Hours"] = man_hour.imports_airside + man_hour.imports_landside + man_hour.exports
if request.method == 'POST':
properties_Form = InputForm(request.POST, instance=man_hour)
if properties_Form.is_valid():
obj = properties_Form.save()
return redirect("%s?pk=%s" % (reverse('form'), obj.pk))
else:
context['form']= InputForm(instance=man_hour)
return render(request, "form.html", context)
HTML
<!DOCTYPE html>
<html>
<head>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js" async></script>
</head>
<body>
<form target="upload_frame" action="." method="post" enctype="multipart/form-data" >
{% csrf_token %}
{{ form.as_p }}<br>
<input type="text" name="Total_Imports" value="{{ Total_Imports }}" class="form-control" disabled><br>
<input type="text" name="Total_Hours" value="{{ Total_Hours }}" class="form-control" disabled><br>
<input type="submit" name="submit" value="Upload" id="submit">
<div class="user_panel">
<a href="/logout">logout</a>
</div>
</form>
</body>
</html>
I am new to Django and I want to understand how can I show a pop up that would tell user that record already exists on this date and station.
I need to understand how can I add an exception handling and show pop up to user?
I've tried to add exception handling using code below but it is not working.
try:
if request.method == 'POST':
properties_Form = InputForm(request.POST, instance=man_hour)
if properties_Form.is_valid():
obj = properties_Form.save()
return redirect("%s?pk=%s" % (reverse('form'), obj.pk))
except IntegrityError as e:
error_message = e.__cause__
print(error_message)
A Form class in Django will perform validation and cleaning for you. It will not raise errors but catch them itself so using a try-except does not make much sense as the form itself has caught the error.
Instead you just need to return a response in case .is_valid() returns False. Furthermore the form itself will render the errors to display it to the user when you render it so you should simply render the same page again:
if request.method == 'POST':
properties_Form = InputForm(request.POST, instance=man_hour)
if properties_Form.is_valid():
obj = properties_Form.save()
return redirect("%s?pk=%s" % (reverse('form'), obj.pk))
context['form'] = properties_Form
return render(request, "form.html", context) # form was not valid so returning a response here
If you want to customize the error message that is generated you can do it by setting the error_messages attribute on the Meta class of the form (See Considerations regarding model’s error_messages [Django docs]):
from django.core.exceptions import NON_FIELD_ERRORS
class InputForm(forms.ModelForm):
class Meta:
model = ManHour
fields = ['date','station', 'imports_airside', 'imports_landside', 'exports']
widgets = {
'date':forms.widgets.DateInput(attrs={'type': 'date', 'max':str(date.today())})
}
error_messages = {
NON_FIELD_ERRORS: {
'unique_together': "%(model_name)s's %(field_labels)s are not unique.",
}
}