Как подключить базу данных PostgreSQL к Django?

Question

Александр @aspitsin138

Django

Как подключить базу данных PostgreSQL к Django?

Всем доброго времени суток!
Не могу найти причину почему таблица не отображается на сайте, возможно отсутствует подключение к базе.
Где искать причину?
settings.py

DATABASES = {
    "default": {
        "ENGINE": "django.db.backends.postgresql_psycopg2",
        "NAME": os.environ.get("DB_NAME", "postgres"),
        "USER": os.environ.get("DB_USER", "postgres"),
        "PASSWORD": os.environ.get("DB_PASSWORD"),
        "HOST": os.environ.get("DB_HOST", "localhost"),
        "PORT": os.environ.get("DB_PORT", "5432"),
    }
}

if os.environ.get("USE_SQLITE", "true").lower() == "true":
    DATABASES["default"] = {
        "ENGINE": "django.db.backends.sqlite3",
        "NAME": BASE_DIR / "db.sqlite3",
    }

models.py

class Item(models.Model):
    url = models.CharField(
        unique=True, max_length=300, verbose_name="Ссылка на страницу товара"
    )
    provider = models.ForeignKey(
        Provider,
        null=True,
        blank=True,
        verbose_name="Поставщик",
        on_delete=models.SET_NULL,
    )
    name = models.CharField(
        max_length=300, null=True, blank=True, verbose_name="Название товара"
    )
    image_url = models.CharField(
        max_length=300,
        null=True,
        blank=True,
        verbose_name="Ссылка на изображение",
    )
    brand = models.ForeignKey(
        Brand,
        null=True,
        blank=True,
        verbose_name="Бренд",
        on_delete=models.SET_NULL,
    )
    vendor_code = models.IntegerField(
        null=True, blank=True, verbose_name="Артикул"
    )
    rating = models.IntegerField(null=True, blank=True, verbose_name="Рейтинг")
    reviews = models.IntegerField(
        null=True, blank=True, verbose_name="Количество отзывов"
    )
    price = models.DecimalField(
        max_digits=10,
        decimal_places=2,
        null=True,
        blank=True,
        verbose_name="Цена без скидки",
    )
    price_with_discount = models.DecimalField(
        max_digits=10,
        decimal_places=2,
        null=True,
        blank=True,
        verbose_name="Цена со скидкой",
    )
    quantity = models.IntegerField(
        null=True, blank=True, verbose_name="Доступно"
    )
    categories = models.ManyToManyField(
        Category, blank=True, verbose_name="Категории"
    )
    quantity_of_purchased = models.IntegerField(
        null=True, blank=True, verbose_name="Количество покупок"
    )
    revenue = models.DecimalField(
        max_digits=35,
        decimal_places=2,
        null=True,
        blank=True,
        verbose_name="Выручка",
    )

    class Meta:
        verbose_name = "Товар"
        verbose_name_plural = "Товары"

    def __str__(self):
        return f"{self.name} {self.brand} [{self.vendor_code}]"

views.py

class ItemListView(LoginRequiredMixin, SubscriptionRequiredMixin, FilterView):
    template_name = "item_list.html"
    paginate_by = 10
    model = Item
    filterset_class = ItemFilter
    filter_backends = DjangoFilterBackend

    def get_queryset(self, **kwargs):
        qs = ItemFilter(self.request.GET, Item.objects.all()).qs
        return qs

    def get_context_data(self, **kwargs):
        table_headers = [
            {"id": "name", "name": "Товар"},
            {"id": "brand", "name": "Бренд"},
            {"id": "provider", "name": "Поставщик"},
            {"id": "rating", "name": "Рейтинг"},
            {"id": "reviews", "name": "Отзывы"},
            {"id": "price_with_discount", "name": "Цена"},
            {"id": "quantity", "name": "Доступно"},
            {"id": "categories", "name": "Категории"},
            {"id": "quantity_of_purchased", "name": "Куплено"},
            {"id": "revenue", "name": "Выручка"},
        ]

        ordering = self.request.GET.get("order_by", None)

        for header in table_headers:
            query = QueryDict(self.request.GET.urlencode(), mutable=True)

            if ordering == f"-{header['id']}":
                query["order_by"] = f"{header['id']}"
            elif ordering != header["id"]:
                query["order_by"] = f"-{header['id']}"
            else:
                query["order_by"] = ""

            query["page"] = 1
            header["url"] = f"?{query.urlencode()}"

        if ordering:
            match_obj = re.match(r"-?(.+)", ordering)
            order_field = match_obj.groups()[0]
            order_field_index = next(
                (
                    index
                    for (index, d) in enumerate(table_headers)
                    if d["id"] == order_field
                ),
                None,
            )
            table_headers[order_field_index]["active"] = True
            table_headers[order_field_index]["down"] = ordering != order_field

        context = super().get_context_data(**kwargs)
        context["table_headers"] = table_headers
        return context

    def get_ordering(self):
        fields = [
            "id",
            "provider",
            "name",
            "brand",
            "vendor_code",
            "rating",
            "reviews",
            "price",
            "price_with_discount",
            "quantity",
            "categories",
            "quantity_of_purchased",
            "revenue",
        ]
        ordering = self.request.GET.get("order_by", "id")

        match_obj = re.match(r"-?(.+)", ordering)

        if match_obj and (match_obj.groups()[0] in fields):
            field = match_obj.groups()[0]

            if field == ordering:
                return [F(field).asc(nulls_first=True)]
            else:
                return [F(field).desc(nulls_last=True)]

        return "id"

Все работало без проблем до Backup и переноса проекта на другой сервер.