Using UpdateView in forms instead of CreateView

Hello Django Forum! I was creating forms using a common template and a part of the form creation is creating views that I than link to my urls. Createview views appear easy to create. However, UpdateView subclassed Views have proven to be a different challenge as they are asking for the field names. Codecademy tells me to use the fields names used in createview but the thing is, I never had a fieldname attribute in my CreateViews subclassed views that utlized a fieldname attribute. I have nothing to go on. I am wondering what I am supposed to put for the fieldname.

I am also having an issue with my finance function view, which says it needs a request as a parameter. I am having that issue in as when I run my code it gives the error type error finance() missing one required argument.

URL configuration for djangodelights project.

The `urlpatterns` list routes URLs to views. For more information please see:
Function views
    1. Add an import:  from my_app import views
    2. Add a URL to urlpatterns:  path('', views.home, name='home')
Class-based views
    1. Add an import:  from other_app.views import Home
    2. Add a URL to urlpatterns:  path('', Home.as_view(), name='home')
Including another URLconf
    1. Import the include() function: from django.urls import include, path
    2. Add a URL to urlpatterns:  path('blog/', include('blog.urls'))
from django.contrib import admin
from django.urls import path, include
# from inventory.views import finance, home, IngredientsView, MenuView, PurchaseView
from inventory import views # with every view imported you need to specify views.viewname as seen in this file in the code below
from django.views.generic.base import TemplateView
from django.http import HttpResponse

urlpatterns = [
    path('', views.home, name='default'), # users don't need to see the rocket page anyway. they need to see the home page.
    path('finance/',, name='finance'),
    path('home/', views.home, name='home'), #I am attempting to connect the home_view function with the views function.
    path('ingredients/', views.IngredientsView.as_view(), name='ingredients'),
    path('menu/', views.MenuView.as_view(), name='menu'),
    path('purchases/', views.PurchaseView.as_view(), name='purchases'), 
    path('menu/add',views.MenuAdditionView.as_view(), name="menuadd"),
    path('ingredient/add', views.IngredientAdditionView.as_view(), name='ingredientadd'), # if class based view it requires an as_view
    # path('ingredient/update', views.UpdateIngredientView.as_view(), name='ingredientupdate'),
    path('recipe/add', views.RecipeAdditionView.as_view(), name='recipeadd'),
    # path('finance',, name='finance'), # this line of code holds the error.
    # finance is not a classed based view therefore i do not need an as_view

from django import forms 
from .models import MenuItem, Ingredient, Purchases, RecipeRequirement

class MenuAdditionForm(forms.ModelForm):
    class Meta:
        model = MenuItem
        fields = ('__all__')

class IngredientAdditionForm(forms.ModelForm):
    class Meta:
        model = Ingredient
        fields = ('__all__')

class UpdateIngredientForm(forms.ModelForm):
    class Meta:
        model = Ingredient
        fields = ('__all__')

class RecipeAdditionForm(forms.ModelForm):
    class Meta:
        model = RecipeRequirement
        fields = ('__all__')
class Purchases(forms.ModelForm):
    class Meta:
        model = Purchases
        fields = ('__all__')

from django.shortcuts import render
from django.urls import path 
from .models import Ingredient, MenuItem, Purchases, RecipeRequirement
from django.views.generic import ListView
# import one at the time write the view for it hook it up in check if it works than move on to the next one. 
from .forms import MenuAdditionForm, IngredientAdditionForm, UpdateIngredientForm, RecipeAdditionForm # link the views and forms togather on this line
# errors can come from importing on the wrong django.views
from django.views.generic.edit import CreateView, UpdateView
from django.http import HttpResponse

# Create your views here.

def finance(request):
    purchased_items = Purchases.objects.all() # this grabs every row in the purchases table

    total_revenue = 0 
    for item in purchased_items:
        total_revenue = total_revenue + item.menu_order.price #this uses the price of each item to calculate the revenue
    total_cost= ingredient_cost_calculate()
    print(str(total_cost) + " this is the total cost calculation")

    total_profit= total_revenue - total_cost
    print(str(total_profit) + "total profit calculation amount")

    return render(request,'inventory/finance.html', {"total_revenue": total_revenue, "total_cost":total_cost, "total_profit": total_profit})    
    # i want the price of the item and the cost of each item.
    # what holds this information? my ingredient model. 
    # it holds the price per unit and the unit.
def ingredient_cost_calculate(): 
    # classes do not store information objects do. 
    # i need the cost per ingredient multiplied by quantity used.
    # I need to than for loop over all of the ingredients in a recipe and than apply the cost per ingredient function or 
    # the same mathematical operation. 
    # classes do not have the data, the objects do.
    # when the customer purchases something an entry is made in the purchases table. 
    # Purchases.objects.all() grabs all of the Purchases data and puts it in a list.
    purchases_objects = Purchases.objects.all() 
    # I need to find all of the ingredients per order. How do I get one order to find the ingredients on. 
    # I need to use a for loop to access each purchase. 
    menu_order_cost = 0 
    for purchase in purchases_objects:
        menu_item_object = purchase.menu_order 
        # recipe requirements is a list of data
        recipe_requirements = RecipeRequirement.objects.filter(recipe=menu_item_object)
        # we iterate over that list with a for loop and access the iteration variable quantity fields. 
        for requirement in recipe_requirements: 
            cost_per_ingredient = requirement.quantity * requirement.ingredient.price_per_unit
            menu_order_cost = menu_order_cost + cost_per_ingredient
    return menu_order_cost


    # the purchases are listed by names they do hold the ingredient data for each indvidual order. 


def home(request):
    return render(request,'inventory/home.html')

class MenuView(ListView):
    # when we specify the model being used for the template its almost as if we import or give access
    # to the html template the class data for us to use for loops and django code on. 
    model = MenuItem
    template_name = 'inventory/menu.html'

class PurchaseView(ListView):
    model = Purchases
    template_name = 'inventory/purchases.html'

class IngredientsView(ListView):
    model = Ingredient
    template_name = "inventory/ingredients.html"

class MenuAdditionView(CreateView):
    model = MenuItem
    template_name = "inventory/form_template.html"
    form_class = MenuAdditionForm

class IngredientAdditionView(CreateView):
    model = Ingredient
    template_name = 'inventory/form_template.html'
    form_class = IngredientAdditionForm

class UpdateIngredientView(UpdateView): # I am thinking this is an UpdateView
    model = Ingredient
    template_name = 'inventory/form_template.html'
    # fields = [] I don't know what to put for fields. Codecademy says put in the same field names as create view but create view does not hold any field names.

class RecipeAdditionView(CreateView):
    model = RecipeAdditionForm
    template_name = 'inventory/form_template.html'

# update view will require a <pk> or slug where I specify what I need to update.
# check out the codecademy section.

# create a view based on the forms made.
# create a path to

for the finance view I do not need a parentheses after the it will call it on its own.

Apparently with updatevidew I need to use field names and field names are the column names of the python model. that is why there is a model = to begin with. so look at the model that it is tied to and grab those values.

keep in mind that if you do use updateview you do not want to provide update view access to fields that you do not want edited in the column. this could result in users messing up things that they should not be allowed to touch.