리스트 화면에서 리뷰 개수와 평점 구하기

from django.shortcuts import render, get_object_or_404, redirect
from third.models import Restaurant, Reviews
from django.core.paginator import Paginator
from third.forms import RestaurantForm, ReviewForm
from django.http import HttpResponseRedirect
from django.db.models import Count

# Create your views here.
def list(request):
    restaurants = Restaurant.objects.all().annotate(reviews_count=Count('reviews'))
    paginator = Paginator(restaurants, 5)

    page = request.GET.get('page')
    items = paginator.get_page(page)

    context = {
        'restaurants': items
    }
    return render(request, 'third/list.html', context)


def create(request):
    if request.method == 'POST':
        form = RestaurantForm(request.POST)
        if form.is_valid():
            new_item = form.save()
        return HttpResponseRedirect('/third/list/')
    form = RestaurantForm()
    return render(request, 'third/create.html', {'form': form})


def update(request):
    if request.method == 'POST' and 'id' in request.POST:
        # item = Restaurant.objects.get(pk=request.POST.get('id'))
        item = get_object_or_404(Restaurant, pk=request.POST.get('id'))
        form = RestaurantForm(request.POST, instance=item)
        if form.is_valid():
            item = form.save()
    elif request.method == 'GET':
        # item = Restaurant.objects.get(pk=request.GET.get('id'))
        item = get_object_or_404(Restaurant, pk=request.GET.get('id'))
        form = RestaurantForm(instance=item)
        return render(request, 'third/update.html', {'form': form})
    return HttpResponseRedirect('/third/list/')


def detail(request, id):
    if 'id' is not None:
        item = get_object_or_404(Restaurant, pk=id)
        reviews = Reviews.objects.filter(restaurant=item).all()
        return render(request, 'third/detail.html', {'item': item, 'reviews': reviews})
    return HttpResponseRedirect('/third/list/')


def delete(request):
    if 'id' in request.GET:
        item = get_object_or_404(Restaurant, pk=request.GET.get('id'))
        item.delete()
    return HttpResponseRedirect('/third/list/')


def review_create(request, restaurant_id):
    if request.method == 'POST':
        form = ReviewForm(request.POST)
        if form.is_valid():
            new_item = form.save()
        return redirect('restaurant-detail', id=restaurant_id)

    item = get_object_or_404(Restaurant, pk=restaurant_id)
    form = ReviewForm(initial={'restaurant': item})
    return render(request, 'third/review_create.html', {'form': form, 'item': item})


def review_delete(request, restaurant_id, review_id):
    item = get_object_or_404(Reviews, pk=review_id)
    item.delete()

    return redirect('restaurant-detail', id=restaurant_id)


def review_list(request):
    reviews = Reviews.objects.all().select_related().order_by('-created_at')
    paginator = Paginator(reviews, 10)

    page = request.GET.get('page')
    items = paginator.get_page(page)

    context = {
        'reviews': items
    }
    return render(request, 'third/review_list.html', context)

▶ 각 음식점의 리뷰 수를 구하거나 평점을 음식점 목록 화면에서 바로 표시할 수 있도록 aggregation 이용

▶ Django ORM에서 제공하는 annotate 메소드는 조회되는 각 레코드들에 대해서 계산을 수행해 데이터를 뽑아낼 때 사용

.annotate(연산 결과를 저장할 속성명 = ORM 연산 메소드('relation 이름')

* Many-to-One 관계에서 부모 레코드에서 자식 레코드의 정보를 연산하는 경우 *
.annotate(연산 결과를 저장할 속성명 = ORM 연산('relation 이름__연산 대상 속성명')

 

 

{% extends 'third/base.html' %}
{% load static %}
{% block content %}
<div class="container">
    {% for item in restaurants %}
    <div class="row restaurant-item" style="margin:20px auto;">
        <div class="col-sm-12">
            <div class="card border-secondary">
                <div class="card-body">
                    <h5 class="card-title">{{ item.name }}</h5>
                    <h6 class="card-subtitle mb-2 text-muted">{{ item.address }}</h6>
                    <p class="card-text">리뷰: {{ item.reviews_count }}</p>
                    <p class="card-text">음식점 설명</p>
                    <a href="{% url 'restaurant-detail' id=item.id %}" class="card-link">자세히 보기</a>
                    <a href="{% url 'restaurant-update' %}?id={{ item.id }}" class="card-link">수정하기</a>
                </div>
            </div>
        </div>
    </div>
    {% endfor %}

    <div class="row">
        <div class="col-sm-12 text-center">
            <div class="pagination">
                <span class="step-links text-center" style="width:100%;">
                    {% if restaurants.has_previous %}
                        <a href="?page=1">&laquo;</a>
                        <a href="?page={{ restaurants.previous_page_number }}">{{ restaurants.previous_page_number }}</a>
                    {% endif %}
                    <span class="current">
                        {{ restaurants.number }}
                    </span>
                    {% if restaurants.has_next and restaurants.next_page_number != restaurants.paginator.num_pages %}
                        <a href="?page={{ restaurants.next_page_number }}">{{ restaurants.next_page_number }}</a>
                        <a href="?page={{ restaurants.paginator.num_pages }}">{{ restaurants.paginator.num_pages }}</a>
                    {% elif restaurants.has_next and restaurants.next_page_number == restaurants.paginator.num_pages %}
                        <a href="?page={{ restaurants.next_page_number }}">{{ restaurants.next_page_number }}</a>
                    {% endif %}
                </span>
            </div>
        </div>
    </div>
</div>
{% endblock %}

▶ 기존의 list.html 파일에 리뷰 개수를 표현할 구문 추가 작성

 

 

from django.shortcuts import render, get_object_or_404, redirect
from third.models import Restaurant, Reviews
from django.core.paginator import Paginator
from third.forms import RestaurantForm, ReviewForm
from django.http import HttpResponseRedirect
from django.db.models import Count, Avg

# Create your views here.
def list(request):
    restaurants = Restaurant.objects.all().annotate(reviews_count=Count('reviews'))\
        .annotate(average_point=Avg('reviews__point'))
    paginator = Paginator(restaurants, 5)

    page = request.GET.get('page')
    items = paginator.get_page(page)

    context = {
        'restaurants': items
    }
    return render(request, 'third/list.html', context)


def create(request):
    if request.method == 'POST':
        form = RestaurantForm(request.POST)
        if form.is_valid():
            new_item = form.save()
        return HttpResponseRedirect('/third/list/')
    form = RestaurantForm()
    return render(request, 'third/create.html', {'form': form})


def update(request):
    if request.method == 'POST' and 'id' in request.POST:
        # item = Restaurant.objects.get(pk=request.POST.get('id'))
        item = get_object_or_404(Restaurant, pk=request.POST.get('id'))
        form = RestaurantForm(request.POST, instance=item)
        if form.is_valid():
            item = form.save()
    elif request.method == 'GET':
        # item = Restaurant.objects.get(pk=request.GET.get('id'))
        item = get_object_or_404(Restaurant, pk=request.GET.get('id'))
        form = RestaurantForm(instance=item)
        return render(request, 'third/update.html', {'form': form})
    return HttpResponseRedirect('/third/list/')


def detail(request, id):
    if 'id' is not None:
        item = get_object_or_404(Restaurant, pk=id)
        reviews = Reviews.objects.filter(restaurant=item).all()
        return render(request, 'third/detail.html', {'item': item, 'reviews': reviews})
    return HttpResponseRedirect('/third/list/')


def delete(request):
    if 'id' in request.GET:
        item = get_object_or_404(Restaurant, pk=request.GET.get('id'))
        item.delete()
    return HttpResponseRedirect('/third/list/')


def review_create(request, restaurant_id):
    if request.method == 'POST':
        form = ReviewForm(request.POST)
        if form.is_valid():
            new_item = form.save()
        return redirect('restaurant-detail', id=restaurant_id)

    item = get_object_or_404(Restaurant, pk=restaurant_id)
    form = ReviewForm(initial={'restaurant': item})
    return render(request, 'third/review_create.html', {'form': form, 'item': item})


def review_delete(request, restaurant_id, review_id):
    item = get_object_or_404(Reviews, pk=review_id)
    item.delete()

    return redirect('restaurant-detail', id=restaurant_id)


def review_list(request):
    reviews = Reviews.objects.all().select_related().order_by('-created_at')
    paginator = Paginator(reviews, 10)

    page = request.GET.get('page')
    items = paginator.get_page(page)

    context = {
        'reviews': items
    }
    return render(request, 'third/review_list.html', context)

▶ 기존 vies.py 파일의 list 메소드를 Avg를 추가해 수정

 

 

{% extends 'third/base.html' %}
{% load static %}
{% block content %}
<div class="container">
    {% for item in restaurants %}
    <div class="row restaurant-item" style="margin:20px auto;">
        <div class="col-sm-12">
            <div class="card border-secondary">
                <div class="card-body">
                    <h5 class="card-title">{{ item.name }}</h5>
                    <h6 class="card-subtitle mb-2 text-muted">{{ item.address }}</h6>
                    <p class="card-text">리뷰: {{ item.reviews_count }}, 평점: {{ item.average_point }}점</p>
                    <p class="card-text">음식점 설명</p>
                    <a href="{% url 'restaurant-detail' id=item.id %}" class="card-link">자세히 보기</a>
                    <a href="{% url 'restaurant-update' %}?id={{ item.id }}" class="card-link">수정하기</a>
                </div>
            </div>
        </div>
    </div>
    {% endfor %}

    <div class="row">
        <div class="col-sm-12 text-center">
            <div class="pagination">
                <span class="step-links text-center" style="width:100%;">
                    {% if restaurants.has_previous %}
                        <a href="?page=1">&laquo;</a>
                        <a href="?page={{ restaurants.previous_page_number }}">{{ restaurants.previous_page_number }}</a>
                    {% endif %}
                    <span class="current">
                        {{ restaurants.number }}
                    </span>
                    {% if restaurants.has_next and restaurants.next_page_number != restaurants.paginator.num_pages %}
                        <a href="?page={{ restaurants.next_page_number }}">{{ restaurants.next_page_number }}</a>
                        <a href="?page={{ restaurants.paginator.num_pages }}">{{ restaurants.paginator.num_pages }}</a>
                    {% elif restaurants.has_next and restaurants.next_page_number == restaurants.paginator.num_pages %}
                        <a href="?page={{ restaurants.next_page_number }}">{{ restaurants.next_page_number }}</a>
                    {% endif %}
                </span>
            </div>
        </div>
    </div>
</div>
{% endblock %}

▶ 기존 list.html에 평점을 표현할 구문 추가 작성

 

 

list 화면