Override Django Unique_Together Validation by adding extra Field - django

Question

I need some help in saving some records to the DB. Work for a parking app and i want to extend the way how unique_together queries the DB, by having an extra param. Just to understand what my situation is.
E.g i give the user possibility of booking a plot on (parking_on) 25th from 9-18 the location P1. Because the way both of the filters are uniques to the DB, someone else can't book the same plot P1 on the same dat 25th but from 19-24 ==>therefore i need some kind of validation here or manually change the way how the unique_together validation works.
Can someone please help?
Please find below my models and admin
from django.db import models
from django.conf import settings
from django.core.exceptions import ValidationError
from django.utils.translation import gettext_lazy as _
from datetime import datetime, timedelta, time
from django.core.exceptions import NON_FIELD_ERRORS
today = datetime.now().date()
tomorrow = today + timedelta(1)
now = datetime.now()
l = now.hour
m = int(now.strftime("%H"))
class ParcareManager(models.Manager):
def active(self, *args, **kwargs):
return super(ParcareManager, self).filter(draft=False).filter(parking_on__lte=datetime.now())
class Parcare(models.Model):
PARKING_PLOT = (('P1', 'Parking #1'),
('P2', 'Parking #2'), ('P3', 'Parking #3'))
user = models.ForeignKey(settings.AUTH_USER_MODEL,
blank=True, null=True, default=1, on_delete=True)
email = models.EmailField(blank=True, null=True)
parking_on = models.DateField(auto_now=False, auto_now_add=False, blank=True, null=True,
help_text='Alege data cand doresti sa vii in office',)
parking_off = models.DateField(auto_now=False, auto_now_add=False, blank=True, null=True,
help_text='Alege Data Plecarii')
numar_masina = models.CharField(max_length=8, default="IF77WXV", blank=True, null=True,
help_text='Introdu Numarul Masinii')
location = models.CharField(max_length=3, blank=True, default="P1", null=True, choices=PARKING_PLOT,
help_text='Alege Locul de Parcare Dorit')
updated = models.DateTimeField(
auto_now=True, auto_now_add=False, blank=True, null=True)
timestamp = models.DateTimeField(
auto_now=False, auto_now_add=True, blank=True, null=True)
venire = models.TimeField(default=time(
9, 00), auto_now=False, auto_now_add=False, help_text='Alege Ora Venirii')
plecare = models.TimeField(default=time(
18, 00), auto_now=False, auto_now_add=False, help_text='Alege Ora Plecarii')
objects = ParcareManager()
def __str__(self):
return self.location + " | " + str(self.parking_on) + " | " + str(self.parking_off)
class Meta:
verbose_name_plural = "parcare"
ordering = ["-parking_on"]
unique_together = ("parking_on", "location")
def clean(self):
if self.parking_on == today: # merge--vedem dak parcam azi
raise ValidationError(
{'parking_on': _('Please book for a date starting tomorrow')})
if self.parking_off < self.parking_on: # merge-vedem daca bookam in trecut
raise ValidationError(
{'parking_off': _('You cant book for a past date!')})
def save(self):
list = []
d = self.parking_on
while d <= self.parking_off:
list.append(
Parcare(user=self.user,
email=self.email,
parking_on=d,
parking_off=d,
location=self.location
)
)
d = d + timedelta(days=1)
Parcare.objects.bulk_create(list)
from django.contrib import admin
from .models import Parcare
class ParcareModelAdmin(admin.ModelAdmin):
list_display = ["user", "location",
"parking_on", "parking_off", "venire", "plecare", "timestamp"]
list_display_links = ["user", "location"]
list_editable = ["parking_off", "parking_on", "venire", "plecare"]
list_filter = ["parking_on", "location", "email"]
search_fields = ["location", "parking_on"]
date_hierarchy = 'parking_on'
class Meta:
model = Parcare
def get_form(self, request, obj=None, **kwargs):
form = super().get_form(request, obj, **kwargs)
if not obj:
user = request.user
form.base_fields['user'].initial = user
form.base_fields['email'].initial = user.email
return form
admin.site.register(Parcare, ParcareModelAdmin)
Thank you in advance!

Answer 1

I just have some thoughts about this problem.
I think the best solution is replace DateField on DateTimeField. Then you can use in clean method something like this (just like an example with bad performance):
def clean(self):
qs = Parcare.objects.filter(location=self.location)
.filter(parking_on__gt=self.parking_on)
.filter(parking_off__lt=self.parking_on)
qs2 = Parcare.objects.filter(location=self.location)
.filter(parking_on__gt=self.parking_off)
.filter(parking_off__lt=self.parking_off)
if len(qs) > 0 or len(qs2) > 0:
raise ValidationError('Time is booked already')
if self.parking_on < datetime.now(): # merge--vedem dak parcam azi
raise ValidationError(
{'parking_on': _('Please book for a time more than now')})
if self.parking_off < self.parking_on: # merge-vedem daca bookam in trecut
raise ValidationError(
{'parking_off': _('You cant book for a past date!')})