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Class Based Views filtering with "def get_queryset(self):" - Assistance with solving issues

I am trying to filter Data in my Web application and having issues to make it work properly.
My application has User model, to whom I assign different programs. Each program contain different exercises.
Program Model:
class Program(models.Model):
patient = models.ForeignKey(User, on_delete=models.CASCADE, default=0)
program_name = models.CharField(max_length=1000, default="")
date_posted = models.DateTimeField(default=timezone.now)
Program View:
class ProgramListView(ListView):
model = Program
template_name = 'program/prog.html'
context_object_name = 'programs'
def get_queryset(self):
return Program.objects.filter(patient=self.request.user)
Program Template:
{% extends "program/base.html" %}
{% block content %}
<h3> Please Choose your Program according to your Plan</h3>
{% for program in programs %}
<article class="media content-section">
<div class="media-body">
<div class="article-metadata">
<a class="mr-2" href="{% url 'program-detail' program.id %}">Program Name - {{ program.program_name }}</a>
</div>
<p class="article-content">Date Posted - {{ program.date_posted }}</p>
</div>
</article>
{% endfor %}
{% endblock content %}
Exercise Model:
class Exercise(models.Model):
program = models.ForeignKey(Program, on_delete=models.CASCADE, default=0)
date_posted = models.DateTimeField(default=timezone.now)
name = models.CharField(max_length=1000, default="")
description = models.TextField(default="")
load_share = models.TextField(default="")
breath_method = models.TextField(default="")
recovery_method = models.TextField(default="")
measure_method = models.TextField(default="")
notes = models.TextField(default="")
extra_info = models.TextField(default="")
reps = models.PositiveSmallIntegerField(default=0)
sets = models.PositiveSmallIntegerField(default=0)
Exercises View (ProgramDetailView):
class ProgramDetailView(DetailView):
model = Exercise
context_object_name = 'exercises'
def get_queryset(self):
program_num = get_object_or_404(Program, pk=self.kwargs.get('pk'))
return Exercise.objects.filter(program=program_num)
Exercises Template:
{% extends "program/base.html" %}
{% block content %}
<h3> Program Exercises List</h3>
{% for exercise in exercises %}
<h3>{{ exercise.name }}</h3>
<h3>{{ exercise.description }}</h3>
{% endfor %}
{% endblock content %}
The Url's:
from django.urls import path
from .import views
from .views import ProgramListView, ProgramDetailView
urlpatterns = [
path('', views.home, name='web-home'),
path('about/', views.about, name='web-about'),
path('programs/', ProgramListView.as_view(), name='web-programs'),
path('programs/<int:pk>/', ProgramDetailView.as_view(), name='program-detail'),
My Program page works well, it shows me all the different programs the User was assign with.
Now, when I try to see the Program exercises (connects to the DetailView), it doesnt work.
I am trying to get the PK of the program and filter it with the help of the
get_object_or_404
The issues I encounter:
Only "pk=1" works (only the first program within the list), it shows me this error though -
TypeError at /programs/1/
'Exercise' object is not iterable
Request Method: GET
Request URL: http://127.0.0.1:8000/programs/1/
Django Version: 3.1
Exception Type: TypeError
Exception Value:
'Exercise' object is not iterable
Exception Location: C:\Users\shai3\Python\lib\site-packages\django\template\defaulttags.py, line 167, in render
Python Executable: C:\Users\shai3\Python\python.exe
Python Version: 3.8.5
Python Path:
['C:\\Users\\shai3\\PycharmProjects\\website',
'C:\\Users\\shai3\\Python\\python38.zip',
'C:\\Users\\shai3\\Python\\DLLs',
'C:\\Users\\shai3\\Python\\lib',
'C:\\Users\\shai3\\Python',
'C:\\Users\\shai3\\Python\\lib\\site-packages']
Server time: Thu, 03 Sep 2020 12:04:29 +0300
It seems like he doesn't get all the exercises in the Data base, It can't use the "For" loop
2.When i try the rest of the programs within the list, I get 404 error -
Page not found (404)
Request Method: GET
Request URL: http://127.0.0.1:8000/programs/2/
Raised by: program.views.ProgramDetailView
No exercise found matching the query
You're seeing this error because you have DEBUG = True in your Django settings file. Change that to False, and Django will display a standard 404 page.
In the SQLite, I do have exercises related to "pk=2" so I am assuming that it at list show me the same error has "pk=1" but it seems like he cant find the exercises in the data base.
Appreciates your help.
Thanks, and I hope I didn't miss any "Code lines".

How to Increment Next Record in Django / Templates

In index.html - I am able to read the first item of my table / model in Django just fine with my code below. However, after the user clicks the next button - I want it to retrieve the next item of my table / model. (how / where do I build this counter?)
here is views.py
def index(request):
flash_dict = {'flashcards': Card.objects.get(pk=1)}
return render(request, 'flash/index.html', context=flash_dict)
here is index.html
<div class = "jumbotron">
{% if flashcards %}
<p class = 'question'>{{ flashcards }}</p>
<p class = 'answer'>{{ flashcards.flash_answer }}</p>
<button type="button" class="btn btn-primary" onclick = "flip()">Flip</button>
<button type="button" class="btn btn-primary">Next</button>
{% else %}
<p>NO ACCESS RECORDS FOUND!</p>
{% endif %}
</div>
here is models.py
from django.db import models
# Create your models here.
class Card(models.Model):
flash_question = models.TextField()
flash_answer = models.TextField()
objects = models.Manager()
def __str__(self):
return self.flash_question
here is urls.py (under base project folder)
from django.contrib import admin
from django.urls import path, include
from flash import views
urlpatterns = [
path('admin/', admin.site.urls),
path('',views.index,name='index'),
]
here is urls.py (under app folder)
from django.conf.urls import url
from flash import views
urlpatterns = [
url(r'^$', views.index, name='index')
]

The semantically 'correct' way to make this work is by rewiring your code significantly:
First, you need to modify urls.py, in your base folder, so that the flashcard URL takes a flashcard ID. This will allow you to visit flashcard/1/, flashcard/2/, etc. and see data for the corresponding flashcard.
urls.py
from django.contrib import admin
from django.urls import path, include
from flash import views
urlpatterns = [
path('admin/', admin.site.urls),
path('flashcard/<int:card>/',views.index,name='flashcard'), # Here we are adding a variable to the URL pattern, which will be passed to the view
]
Next, you need to modify your view so that it takes a flashcard ID from the URL and renders the flashcard in question:
views.py
def flashcard(request, card=1): # Your view will now look for the 'card' variable in your URL pattern.
flash_dict = {'flashcards': Card.objects.get(pk=card)} # Your 'flashcards' variable now holds the card that corresponds to the ID in the URL
return render(request, 'flash/index.html', context=flash_dict)
Then, we'll write a method within your Card model that will pull the next card when self.get_next is called. Now, if you have a Card object, you can find the next card by calling card.get_next():
models.py
from django.db import models
# Create your models here.
class Card(models.Model):
flash_question = models.TextField()
flash_answer = models.TextField()
objects = models.Manager()
def __str__(self):
return self.flash_question
def get_next(self):
next = Card.objects.filter(id__gt=self.id).order_by('id').first()
if next:
return next
# If the current card is the last one, return the first card in the deck
else:
return Card.objects.all().order_by('id').first()
Finally, we'll replace the buttons in your template with an a href that links to the new 'flashcard' view, and passes it the ID of the next card in the sequence:
template.html
<div class = "jumbotron">
{% if flashcards %}
<p class = 'question'>{{ flashcards }}</p>
<p class = 'answer'>{{ flashcards.flash_answer }}</p>
<!-- Here we link to the 'flashcard' view, and pass it the ID of the next card in the sequence -->
Next flashcard
{% else %}
<p>NO ACCESS RECORDS FOUND!</p>
{% endif %}
</div>
Now, try visiting /flashcard/1 to see how everything works together.

Django - No Reverse Match Error - URL only works with static values

I'm working on a Django site that displays a list of projects. You go to a page, you see a project, you click it, and you can then see project details and have the option to edit the page.
For each individual project, I use a template called project.html. Then on that page, I have a link to edit_project.html
Edit Project
Whenever I try to load the project page to view, I get this error:
Reverse for 'edit_project' with arguments '('',)' not found. 1
pattern(s) tried: ['edit_project/(?P\d+)/$']
I checked the urls, and they seemed fine. So, I tried hard-coding a project id that I knew was in the database. For example, I called:
Edit Project
instead of calling that same thing with "project.id". When I did that, the error went away.
Why does this work with a hard-coded value instead of a project.id variable?
I also tried deleting the database and all the migrations in case something strange was happening there. I got the same issue though.
Here is the code I used to set everything up in case it is helpful.
project.html
{% extends "profile/base.html" %}
{% block content %}
<p>
Edit Project
</p>
<p>Status: {{ status }}</p>
{% endblock content %}
edit_project.html
{% block content %}
<p>{{ project }}</p>
<p>Edit project:</p>
<form action="{% url 'profile:edit_project' project.id %}" method='post'>
{% csrf_token %}
{{ form.as_p }}
<button name="submit">Save Changes</button>
</form>
{% endblock content %}
views.py
#login_required
def edit_project(request, project_id):
"""Edit an existing project"""
project = Project.objects.get(id=project_id)
#Make sure the project belongs to the owner
if project.owner != request.user:
return Http404
if request.method != 'POST':
#Initial request; pre-fill form with the current entry
form = ProjectForm(instance=project)
else:
#POST data submitted; process data
form = ProjectForm(instance=project, data=request.POST)
if form.is_valid():
form.save()
return HttpResponseRedirect(reverse('profile:project',args=[project.id]))
context = {'project':project, 'form':form}
return render(render, 'profile/edit_project.html', context)
(project) forms.py
class DateInput(forms.DateTimeInput):
input_type = 'date'
class ProjectForm(forms.ModelForm):
class Meta:
model = Project
fields = ['name','description','status', 'project_type', 'start_date','end_date', 'due_date']
labels = {'name':'Name', 'description':'Description:', 'status':'Status', 'project_type':'Project Type',
'start_date':'Start Date', 'end_date':'End Date', 'due_date': 'Due Date',}
widgets ={'description':forms.Textarea(attrs={'cols':80}),'start_date':DateInput(),
'end_date':DateInput(),'due_date':DateInput()}
urls.py
urlpatterns = [
#Home page
url('^$', views.index, name='index'),
#Show all projects
url('projects/$', views.projects, name='projects'),
#Details for single project
url('^projects/(?P<project_id>\d+)/$', views.project, name='project'),
#Page for editing a single project
url('^edit_project/(?P<project_id>\d+)/$', views.edit_project, name='edit_project'),
]

django getting error about views.py

This is my views.py
from django.shortcuts import render
from . models import Houses
def houses_list(request):
house = Houses.objects.all().order_by('owner')
return render('Houses.html',{'houses':house})
this my models.py
from django.db import models
class Houses(models.Model):
owner = models.CharField(max_length=250)
house_name = models.CharField(max_length=500)
country = models.CharField(max_length=500)
genre = models.CharField(max_length=100)
def __str__(self):
return self.house_name
class house(models.Model):
houses = models.ForeignKey(Houses, on_delete=models.CASCADE)
file_type = models.CharField(max_length=10)
house_title = models.CharField(max_length=250)
this my url.py
from django.urls import path
from . import views
urlpatterns= [
path('', views.Houses, name='Houses'),
]
this my html file
{% load static %}
<html>
<head>
<meta charset = "utf-8">
<title>Houses</title>
</head>
<body>
<h1>House list</h1>
<div class="house">
{% for house in houses %}
<div class="house">
<h2>{{Houses.house_name}}</h2>
<p>{{Houses.owner}}</p>
<p>{{Houses.genre}}</p>
</div>
{% endfor %}
</div>
</body>
</html>
I'm tring to get the data from my database but on the web getting attribute no object error.But I can see the all objects on the admin page do you have any idea what I'm doing wrong?

Here is code with fixed bugs:
The bug in urls was causing AttributeError. Fix code to:
urlpatterns= [
path('', views.houses_list, name='Houses'),
]
Remember that urls must point to views. But after you fix this, the next error will be in the views.py, because render() is missing request argument. Change to:
def houses_list(request):
house = Houses.objects.all().order_by('owner')
return render(request, 'Houses.html',{'houses':house})
The bug in the template would just render empty. Fix to:
{% for house in houses %}
<div class="house">
<h2>{{house.house_name}}</h2>
<p>{{house.owner}}</p>
<p>{{house.genre}}</p>
</div>
{% endfor %}

You are trying to get attributes from the Houses class in your template. Replace Houses with house, which is the current Houses object returned by the for loop. `
<h1>House list</h1>
<div class="house">
{% for house in houses %}
<div class="house">
<h2>{{house.house_name}}</h2>
<p>{{house.owner}}</p>
<p>{{house.genre}}</p>
</div>
{% endfor %}
</div>
EDIT
As Borut mentioned, your render call in houses_list is missing the request, i.e.
return render(request, ...)
Also, your urlpatterns is referencing Houses model instead of the houses_list view, i.e. it should be views.houses_list instead of views.Houses.

Adding a custom placeholder to django-cms

I'm trying to create a custom placeholder to add an admin-editable section on a website. Django-cms' documentation is really generic about what's to be done to add it.
The placeholder lives in a separate app, called contacts, already added to the settings.py file
Here's my code up to now (skipping imports to be less verbose):
models.py
class ContactsPlaceholder(models.Model):
phone = models.CharField(max_length=100)
email = models.CharField(max_length=100)
address = models.TextField(max_length=700)
# your fields
my_placeholder = PlaceholderField('contacts_contactsplaceholder')
# your methods
def __unicode__(self):
return "Contacts Placeholder"
views.py
def contacts(request):
# Load the the contacts from db
contactsfields = ContactsField.objects.all()
contacts_placeholder = ContactsPlaceholder.objects.all()
context = {"contactsfields" : contactsfields, "contacts_placeholder" : contacts_placeholder}
return render(request, "../templates/contacts.html", context)
def contacts_placeholder_detail(request, id): # is this really useful?
object = get_object_or_404(ContactsPlaceholder, id=id)
return render_to_response('../templates/contacts_placeholder_detail.html', {
'object': object,
}, context_instance=RequestContext(request))
contacts.html
{% extends "base.html" %}
{% load cms_tags %}
{% block content %}
<div>
<h1>Contacts</h1>
{% placeholder "contacts_placeholder" or %}
<p>Placeholder is empty</p>
{% endplaceholder %}
</div>
{% endblock content %}
and finally, admin.py
class ContactsPlaceholderAdmin(PlaceholderAdminMixin, admin.ModelAdmin):
# Editable fields
frontend_editable_fields = ("phone", "email", "address")
# Form fields order and sections
fieldsets = [
(None,{"fields" : ["phone", "email", "address"]})
]
admin.site.register(ContactsPlaceholder, ContactsPlaceholderAdmin)
With this configuration, after having run python manage.py syncdb I do get "Placeholder is empty" in the html response, and of course the placeholder is not editable using the standard frontend editor, which was the desired behaviour.
Going to 127.0.0.1:8000/admin/ i can see the "Contacts Placeholder" table, however when I click it or try to add items I do get the following error:
OperationalError at /us/admin/contacts/contactsplaceholder/
no such column: contacts_contactsplaceholder.phone

If the contacts() view is rendered via an app hook then using {% placeholder "contacts_placeholder" %} in the template won't work.
When using Placeholders in apps connected to the CMS via an AppHook you must use {% static_placeholder "MyPlaceholder" %} instead of the usual {% Placeholder "MyPlaceholder" %}
If you've got an app or a plugin in which you've created a PlaceholderField, then in your template which renders that, you'd need the following tag;
{% render_placeholder instance.placeholderfieldname %}