Django templates - how to run a method on a variable? - django

Question

I'm new to Django, so maybe my attempts are pure heresy ;)
I'm trying to make a view which lists disponible conference rooms with its attributs, availability included.
I have 2 models: Room and Reservation. I'd like in the view to have a column saying if the room is available the day the page is displayed.
My models.py:
from django.utils import timezone
from django.db import models
class Room(models.Model):
name = models.CharField(max_length=255, unique=True)
capacity = models.IntegerField()
projector = models.BooleanField()
class Reservation(models.Model):
room = models.ForeignKey(Room, on_delete=models.CASCADE)
date = models.DateField()
comment = models.CharField(max_length=255)
class Meta:
unique_together = ('room', 'date',)
my views.py:
class ShowRoom(View):
def get(self, request):
rooms = Room.objects.all()
time_now = timezone.now().date()
context = {
'rooms': rooms,
'time_now': time_now
}
return render(request, 'rooms/list_rooms.html', context)
My template:
{% extends 'rooms/base.html' %}
{% block block_title %} Home {% endblock %}
{% block block_content %}
{% if rooms %}
<table class="table">
<thead>
<td> Name </td>
<td> Capacity </td>
<td> Available </td>
<td> Projector </td>
</thead>
<tbody>
{% for room in rooms|dictsort:'capacity' %}
<tr>
<td> {{ room.name }} </td>
<td> {{ room.capacity }} </td>
<td> Available? </td>
<td> {{ room.projector|yesno:'yes,no' }} </td>
</tbody>
{% endfor %}
</table>
{% else %}
<h1> You have no registered rooms yet. </h1>
{% endif %}
{% endblock %}
Everything works fine, I need just to replace this <td> Available? </td> line with a code, which would display "free" or "occupied" according to existing room reservations.
I've found out that maybe I should write a custom filter.
Here is my filter:
from django import template
from rooms.models import Room, Reservation
register = template.Library()
#register.filter
def check_reservation(queryset, now):
return queryset.filter(date=now)
(I wanted first to make it working, and after make it display this "free" or "occupied".)
I've added to the template {% load my_extras %} and replaced the line I want to change with
<td> {{ room.reservation_set.all|check_reservation:'time_now' }} </td>
The output is:
ValidationError at /room/ ["'time_now' value has an invalid date
format. It must be in YYYY-MM-DD format."]
Before adding the filter, I was trying this solution in the shell and it was working.
I don't know if there is something wrong with the filter, or I try to approach the issue from wrong side.
Thanks in advance for any tips.

Answer 1

Try adding another field to the the Room class:
occupied = model.BooleanField(default=False)
In the views you can check the date associated with the reservation and today's date.
if reservation.date == time_now:
room.occupied = true
You can then filter with rooms that are available and which are not.
rooms_occupied = room.objects.filter(occupied=True)
rooms_available = room.object.filter(occupied=False)
In the template:
{% if rooms_occupied %}
Available
{% endif %}