• Принцип DRY
• Функции высшего порядка
• Декораторы
• Декораторы в Django
• Function Based View
• Class Based View
• Generic Based View
• Схема выбора
• Дополнительная литература

Принцип DRY

• D: on't
  не
• R: epeat
  повторяй
• Y: ourself
  -ся

Функции высшего порядка

Функции, принимающие на вход другие функции или возвращающие функцию в качестве результата

def f(data, func):
    return [func(e) for e in data]

print(f([1, 2, 3], lambda x: x*2))

- [2, 4, 6]

def f(x):
    def w(y):
        return x + y
    return w
plus_10 = f(10)
print(plus_10(1))
print(plus_10(113))

- 11
- 123

Декораторы

#
# Callable[[Args], Result]
#
C = Callable[[Any], Any]
Callable[[C], C]

Декораторы в Django

https://docs.djangoproject.com/en/4.2/topics/http/decorators/

Function Based View

# Function Based Views
from django.shortcuts import render, get_object_or_404, redirect

from .forms import TaskForm, ConfirmForm
from .models import Task


def task_list_view(request):
    return render(request, 'todo/task_list.html', {
        'tasks': Task.objects.all(),
    })


def task_create_view(request):
    if request.method == 'POST':
        form = TaskForm(data=request.POST)
        if form.is_valid():
            task = form.save()
            return redirect('task-detail', pk=task.pk)

    return render(request, 'todo/task_create.html', {
        'form': TaskForm(),
    })


def task_detail_view(request, pk):
    task = get_object_or_404(Task, pk=pk)

    return render(request, 'todo/task_detail.html', {
        'task': task,
    })


def task_update_view(request, pk):
    task = get_object_or_404(Task, pk=pk)

    if request.method == 'POST':
        form = TaskForm(instance=task, data=request.POST)
        if form.is_valid():
            form.save()
            return redirect('task-detail', pk=task.pk)

    return render(request, 'todo/task_update.html', {
        'task': task,
        'form': TaskForm(instance=task),
    })


def task_delete_view(request, pk):
    task = get_object_or_404(Task, pk=pk)

    if request.method == 'POST':
        form = ConfirmForm(data=request.POST)
        if form.is_valid():
            task.delete()
            return redirect('task-list')

    return render(request, 'todo/task_confirm_delete.html', {
        'task': task,
        'form': ConfirmForm(),
    })

Class Based View

# Class Based Viwes
from django.shortcuts import render, get_object_or_404, redirect
from django.views import View

from .forms import TaskForm, ConfirmForm
from .models import Task


class TaskListView(View):

    def get(self, request, *args, **kwargs):
        return render(request, 'todo/task_list.html', {
            'tasks': Task.objects.all(),
        })


class TaskCreateView(View):

    def get(self, request, *args, **kwargs):
        return render(request, 'todo/task_create.html', {
            'form': TaskForm(),
        })

    def post(self, request, *args, **kwargs):
        form = TaskForm(data=request.POST)
        if form.is_valid():
            task = form.save()
            return redirect('task-detail', pk=task.pk)

        return self.get(request)


class TaskDetailView(View):

    def get(self, request, pk, *args, **kwargs):
        task = get_object_or_404(Task, pk=pk)

        return render(request, 'todo/task_detail.html', {
            'task': task,
        })


class TaskUpdateView(View):

    def get(self, request, pk, *args, **kwargs):
        task = get_object_or_404(Task, pk=pk)
        return render(request, 'todo/task_update.html', {
            'task': task,
            'form': TaskForm(instance=task),
        })

    def post(self, request, pk, *args, **kwargs):
        task = get_object_or_404(Task, pk=pk)
        form = TaskForm(instance=task, data=request.POST)
        if form.is_valid():
            form.save()
            return redirect('task-detail', pk=task.pk)

        return self.get(request, pk)


class TaskDeleteView(View):

    def get(self, request, pk, *args, **kwargs):
        task = get_object_or_404(Task, pk=pk)
        return render(request, 'todo/task_confirm_delete.html', {
            'task': task,
            'form': ConfirmForm(),
        })

    def post(self, request, pk, *args, **kwargs):
        task = get_object_or_404(Task, pk=pk)
        form = ConfirmForm(data=request.POST)
        if form.is_valid():
            task.delete()
            return redirect('task-list')

        return self.get(request, pk)

Generic Based View

# Generic Based Views
from django.views.generic import ListView, DetailView, DeleteView, UpdateView, CreateView

from .models import Task


class TaskListView(ListView):
    model = Task
    context_object_name = 'tasks'


class TaskCreateView(CreateView):
    model = Task
    context_object_name = 'task'
    fields = ('name', 'description', 'is_done')
    template_name = 'todo/task_create.html'


class TaskDetailView(DetailView):
    model = Task
    context_object_name = 'task'


class TaskUpdateView(UpdateView):
    model = Task
    context_object_name = 'task'
    fields = ('name', 'description', 'is_done')
    template_name = 'todo/task_update.html'


class TaskDeleteView(DeleteView):
    model = Task
    context_object_name = 'task'
    success_url = '/'

Схема выбора

Дополнительная литература

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