Artyom Lazovikov's questions

我正在尝试将 djangorestregistration 绑定到我的项目中，我做错了什么并且发生了错误

堆栈跟踪

System check identified no issues (0 silenced).
March 29, 2020 - 11:09:52
Django version 3.0.4, using settings 'e_shop.settings'
Starting development server at http://127.0.0.1:8000/
Quit the server with CONTROL-C.
Internal Server Error: /
Traceback (most recent call last):
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/core/handlers/exception.py", line 34, in inner
    response = get_response(request)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/debug_toolbar/middleware.py", line 99, in __call__
    bits[-2] += toolbar.render_toolbar()
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/debug_toolbar/toolbar.py", line 69, in render_toolbar
    return render_to_string("debug_toolbar/base.html", context)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/template/loader.py", line 62, in render_to_string
    return template.render(context, request)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/template/backends/django.py", line 61, in render
    return self.template.render(context)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/template/base.py", line 171, in render
    return self._render(context)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/test/utils.py", line 95, in instrumented_test_render
    return self.nodelist.render(context)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/template/base.py", line 936, in render
    bit = node.render_annotated(context)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/template/base.py", line 903, in render_annotated
    return self.render(context)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/template/defaulttags.py", line 309, in render
    return nodelist.render(context)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/template/base.py", line 936, in render
    bit = node.render_annotated(context)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/template/base.py", line 903, in render_annotated
    return self.render(context)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/template/defaulttags.py", line 443, in render
    url = reverse(view_name, args=args, kwargs=kwargs, current_app=current_app)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/urls/base.py", line 55, in reverse
    app_list = resolver.app_dict[ns]
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/urls/resolvers.py", line 521, in app_dict
    self._populate()
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/urls/resolvers.py", line 485, in _populate
    {**defaults, **url_pattern.default_kwargs},
TypeError: 'URLResolver' object is not a mapping

网址

from django.contrib import admin
from django.urls import path, include
from django.conf.urls.static import static
from django.conf import settings


apipatterns = [
path('accounts/', include('rest_registration.api.urls')),
]

urlpatterns = [
path('admin/', admin.site.urls),
path('api/', include((apipatterns, 'api'), namespace='api')),
path('', include('products.urls'),
path('api/v1/', include(apipatterns)),
)] + static(settings.MEDIA_URL, document_root = settings.MEDIA_ROOT)

if settings.DEBUG:
    import debug_toolbar
    urlpatterns = [
        path('__debug__/', include(debug_toolbar.urls)),

    ] + urlpatterns

设置

import os

# Build paths inside the project like this: os.path.join(BASE_DIR, ...)
BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
TEMPLATE_DIR = os.path.join(BASE_DIR, 'templates')
STATICFILE_DIR = os.path.join(BASE_DIR, 'static')

# Quick-start development settings - unsuitable for production
# See https://docs.djangoproject.com/en/3.0/howto/deployment/checklist/

# SECURITY WARNING: keep the secret key used in production secret!
SECRET_KEY = 'qcfgnc+)aksmye+@7^dmkuubkgko65z@^3eszh=cl6x%&g749!'

# SECURITY WARNING: don't run with debug turned on in production!
DEBUG = True

ALLOWED_HOSTS = []


# Application definition

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'rest_framework',
    'rest_framework.authtoken',
    'products',
    'users',
    'orders',
    'django_extensions',
    'debug_toolbar',
    'django_filters',
    'rest_registration',

]

AUTH_USER_MODEL = 'users.User'

MIDDLEWARE = [
    'django.middleware.security.SecurityMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
    'debug_toolbar.middleware.DebugToolbarMiddleware',
]

ROOT_URLCONF = 'e_shop.urls'

TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'DIRS': [
        TEMPLATE_DIR
        ],
        'APP_DIRS': True,
        'OPTIONS': {
            'context_processors': [
                'django.template.context_processors.debug',
                'django.template.context_processors.request',
                'django.contrib.auth.context_processors.auth',
                'django.contrib.messages.context_processors.messages',
            ],
        },
    },
]

WSGI_APPLICATION = 'e_shop.wsgi.application'


# Database
# https://docs.djangoproject.com/en/3.0/ref/settings/#databases

REST_FRAMEWORK = {
    'DEFAULT_FILTER_BACKENDS': ('django_filters.rest_framework.DjangoFilterBackend',)
}

REST_REGISTRATION = {
    'REGISTER_VERIFICATION_ENABLED': False,
    'RESET_PASSWORD_VERIFICATION_ENABLED': False,
    'REGISTER_EMAIL_VERIFICATION_ENABLED': False,
}

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
    }
}

# Password validation
# https://docs.djangoproject.com/en/3.0/ref/settings/#auth-password-validators

AUTH_PASSWORD_VALIDATORS = [
    {
        'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',
    },
]


# Internationalization
# https://docs.djangoproject.com/en/3.0/topics/i18n/

INTERNAL_IPS = [
    '127.0.0.1',
]

LANGUAGE_CODE = 'ru-ru'

TIME_ZONE = 'Europe/Moscow'

USE_I18N = True

USE_L10N = True

USE_TZ = True

# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/3.0/howto/static-files/

MEDIA_ROOT = os.path.join(BASE_DIR, 'media')
MEDIA_URL ='/media/'
STATIC_URL = '/static/'
STATICFILES_DIRS = [
    STATICFILE_DIR
]

楷模

class Product(models.Model):
    name = models.CharField(max_length=150, db_index=True,
                            verbose_name='Название')
    slug = models.SlugField(max_length=150, db_index=True)
    price = models.DecimalField(max_digits=10, decimal_places=2, 
                                verbose_name='Цена')
    category = models.ForeignKey(Category, 
                                 related_name='category',
                                 null=True,
                                 blank=True,
                                 verbose_name='Категория',
                                 on_delete=models.CASCADE,
                                 )
    sales = models.ManyToManyField(Sale, 
                                   related_name='sales',
                                   verbose_name='Скидка',
                                   blank=True
                                   )

class Sale(models.Model):
    name = models.CharField(max_length=150)
    description = models.CharField(max_length=255)
    percent = models.IntegerField(verbose_name='Процент')

    class Meta:
        ordering = ('name', 'percent')
        verbose_name = 'Скидка'
        verbose_name_plural = 'Скидки'

    def __str__(self):
        return self.name

序列化器

class SaleSerializer(serializers.ModelSerializer):
    class Meta:
        model = Sale
        fields = ['name', 'percent']


class ProductSerializer(serializers.ModelSerializer):
    category = CategorySerializer(read_only=True)
    sale = SaleSerializer(many=True, read_only=True)

    class Meta:
        model = Product
        fields = ['slug', 'name', 'price', 'sale',
                  'category']

        lookup_field = 'slug'

看法

class ProductsBySales(ListAPIView):
    serializer_class = ProductSerializer
    filterset_class = ProductSaleFilter

    def get_queryset(self):
        return Product.objects.exclude(sales=None)

前面给出的对象：

[
    {
        "slug": "8",
        "name": "8",
        "price": "1.00",
        "category": {
            "name": "phones",
            "parental_category": null
        },
    },

实施重击时出错，在什么方面-我不明白

追溯

Traceback (most recent call last):
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/db/models/fields/__init__.py", line 1772, in get_prep_value
    return int(value)
ValueError: invalid literal for int() with base 10: 'bytovaya-tehnika'

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/core/handlers/exception.py", line 34, in inner
    response = get_response(request)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/core/handlers/base.py", line 115, in _get_response
    response = self.process_exception_by_middleware(e, request)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/core/handlers/base.py", line 113, in _get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/views/decorators/csrf.py", line 54, in wrapped_view
    return view_func(*args, **kwargs)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/views/generic/base.py", line 71, in view
    return self.dispatch(request, *args, **kwargs)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/rest_framework/views.py", line 505, in dispatch
    response = self.handle_exception(exc)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/rest_framework/views.py", line 465, in handle_exception
    self.raise_uncaught_exception(exc)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/rest_framework/views.py", line 476, in raise_uncaught_exception
    raise exc
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/rest_framework/views.py", line 502, in dispatch
    response = handler(request, *args, **kwargs)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/rest_framework/generics.py", line 199, in get
    return self.list(request, *args, **kwargs)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/rest_framework/mixins.py", line 38, in list
    queryset = self.filter_queryset(self.get_queryset())
  File "/home/artyomlazovikov/internet_shop/e_shop/products/views.py", line 37, in get_queryset
    queryset = Product.objects.filter(category=category)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/db/models/manager.py", line 82, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/db/models/query.py", line 904, in filter
    return self._filter_or_exclude(False, *args, **kwargs)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/db/models/query.py", line 923, in _filter_or_exclude
    clone.query.add_q(Q(*args, **kwargs))
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/db/models/sql/query.py", line 1350, in add_q
    clause, _ = self._add_q(q_object, self.used_aliases)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/db/models/sql/query.py", line 1381, in _add_q
    check_filterable=check_filterable,
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/db/models/sql/query.py", line 1311, in build_filter
    condition = self.build_lookup(lookups, col, value)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/db/models/sql/query.py", line 1165, in build_lookup
    lookup = lookup_class(lhs, rhs)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/db/models/lookups.py", line 22, in __init__
    self.rhs = self.get_prep_lookup()
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/db/models/fields/related_lookups.py", line 115, in get_prep_lookup
    self.rhs = target_field.get_prep_value(self.rhs)
  File "/home/artyomlazovikov/internet_shop/.venv/lib/python3.7/site-packages/django/db/models/fields/__init__.py", line 1776, in get_prep_value
    ) from e
ValueError: Field 'id' expected a number but got 'bytovaya-tehnika'.

模型产品，类别。M2M 关系。

class Category(models.Model):
    name = models.CharField(max_length=255)
    slug = models.SlugField(max_length=255, db_index=True)
    parental_category = models.ManyToManyField('self', 
                                                blank=True,
                                                verbose_name='Категория-родитель',
                                                )


    def __str__(self):
        return self.name

class Product(models.Model):
    name = models.CharField(max_length=150, db_index=True,
                            verbose_name='Название')
    slug = models.SlugField(max_length=150, db_index=True)
    category = models.ForeignKey(Category, 
                                 related_name='category',
                                 null=True,
                                 blank=True,
                                 verbose_name='Категория',
                                 on_delete=models.SET_NULL,
                                 )

    def __str__(self):
        return self.name

序列化器

class ProductSerializer(serializers.ModelSerializer):
    category = CategorySerializer(many=True, read_only=True)

    class Meta:
        model = Product
        fields = ['id','name','slug',
                  'category']

class CategorySerializer(serializers.ModelSerializer):
    class Meta:
        model = Category
        fields = ['name', 'parental_category']

意见

class ProductList(ListAPIView):
    serializer_class = ProductSerializer

    def get_queryset(self):
        queryset = Product.objects.all()
        category = self.kwargs['category_slug']
        if category is not None:
            queryset = Product.objects.filter(category=category)
        return queryset

为类别表中的每条记录显示新闻表中的记录数。按类别名称升序排列记录

M2M 通信

您好，ORM 有问题

from django.db import models
from django.conf import settings


class Category(models.Model):
    name = models.CharField(max_length=200)

    def __str__(self):
        return self.name

class News(models.Model):
    title = models.CharField(max_length=200)
    body = models.TextField()
    is_published = models.BooleanField(default=False)
    category = models.ManyToManyField(Category)

    def publish(self):
        self.is_published = True
        self.save()

    def __str__(self):
        return self.title

我可以写一个对 posgresql 的请求，但我仍然不知道如何将它传输到 django ORM。

SELECT ct.name, count(n.category_id) FROM category ct 
LEFT JOIN news n ON ct.id=n.category_id 
GROUP BY ct.name, category_id 
ORDER BY category_id DESC

我不明白如何使用聚合函数并从选择中获取必要的字段

from django.db import models
from django.conf import settings


class Category(models.Model):
    name = models.CharField(max_length=200)

    def __str__(self):
        return self.name

class News(models.Model):
    title = models.CharField(max_length=200)
    body = models.TextField()
    is_published = models.BooleanField(default=False)
    category = models.ManyToManyField(Category)

    def publish(self):
        self.is_published = True
        self.save()

    def __str__(self):
        return self.title

如何实现这个要求？

SELECT n.*, cat.name FROM news n LEFT JOIN category cat ON n.category_id=cat.id;

我是 ORM 的新手，我正在尝试通过示例来解决这个问题，使用谷歌，显然我不知道如何，如果我在 2 天内挖掘得很少

DELETE FROM news WHERE id IN (SELECT id FROM news ORDER BY id DESC LIMIT 100)

从表中删除最后 100 条记录

有一个任务 - 向表中添加 500 条唯一记录

BOTTOM PSEUDOCODE 是否可以将其转换为 SQL 查询？我可以对 sql 中的 attrname, ... 字段进行操作吗？

attrname = 0
attrname2 = 0
counter = 0

WHILE counter <> 500
    counter += 1;
    attrname += 1;
    attrname2 += 1;
    INSERT INTO tablename(fieldname1, fieldname2) VALUES (attrname, attrname2);
END LOOP

我在哪里可以阅读有关 TO_CHAR、TO_INT、TO_BOOL 等方法的信息。推荐postgreSQL方言书

有这样一行——

str = 'a, b, c, d, "e, f, g"'

底线是你需要用逗号分割这个字符串，但不要分割双引号内的元素。

获取内容的示例：

['a', 'b', 'c', 'd', "e, f, g"]

这是代码，但它不保留顺序，因此使用不合适

例子。

из строки '"""asd"""'
нужно получить '""asd""' 
strip('"', 1)

   @classmethod
    def _get_header(cls):
        _non_validate = ['{\n', '},\n', '}\n}']
        _headers = []
        with FileManager(cls.file, 'r') as f:
            for line in f.readlines():
                if not any(_non_validate) in line:
                    _headers.append(line.split(':')[0].strip('\t"'))
        return _headers

有一个功能。我希望它检查字符串中是否至少有一个_non_validate值，如果没有，则将其附加到列表中。如何在语法上正确地将其转换为代码，我的不起作用。

   File "/home/artsiom/Desktop/python/JsonPythonConverter/JsonToCsv (1).py", line 115, in _get_header
    if not any(_non_validate) in line:
TypeError: 'in <string>' requires string as left operand, not bool

这是错误消息

def __init__(self):
    self.csvfile = input("Enter the name of .csv file : ")
    if not os.path.exists(self.csvfile):
        print("File doesn't exist")
        self.__init__()

任何输入 - 使用 print("File doesn't exist") 跳转到分支

该文件与脚本位于同一目录中

我希望该方法__str__()显示类实例的名称，但我不知道该怎么做。

def __str__(self):
    return f'name : {self.__name__()} .Size : [{self.n};{self.m}]. Matrix : {self.matrix}'

建议一种方法来计算列表中每个元素的重复次数。Python

我需要通过 c# 打开一个 excel 工作簿。无需处理数据，只需在另一个 Windows 窗口中打开即可。

我想出的东西行不通。

n, m = [int(x) for x in input().split(" ")]
field = [[0 * m] * n]
print(field)

期待 [[], [], [], []]，返回 [[]]

我很可能做错了什么。

如果输入字符串的至少一个字母为大写，则需要更改字母表的大小写。

if str_list_of_letters.isupper():
   alphabet = list(''.join(alphabet).upper())

根据文档判断，如果字符串包含至少 1 个大写字符，则 str.isupper() 方法返回 True。

如果字符串中的所有大小写字符都是大写的并且字符串中至少有一个大小写字符，则字符串是大写的。

如果我错了 - 纠正我。问题 - 是否可以检查是否至少有一个大写字母，而不检查循环中的每个字符？关于底部的同样问题。

     class Student
    {
        private string name;
        private string lastname;
        private int age;
        private int course;

        public Student(string a, string b, int c, int d)
        {
            this.name = a;
            this.lastname = b;
            this.age = c;
            this.course = d;
        }
    }

我想出了输出信息的方法。现在的问题是，类实例的列表在哪里，以便后续使用它们？理想情况下，扔掉一个我可以阅读的资源。

        result = 1;
        int j = 1;
        for (int i = 0; i < NumOfEl; i++)
        {
            if (FirstMass[i] == 0)
            {
                while (i + j < NumOfEl && FirstMass[i + j] != 0)
                {
                    result *= FirstMass[i + j];
                }
            }
        }

这是我的代码，数组的大小是从键盘输入的，元素是随机给定的。第一个 null - 第一个值为 0 的元素

问题是我做错了什么，以及如何做对？我知道该任务在 2 个周期内运行，但我已经得到 index is out of range 3 小时了。

假设我有 2 个列表，一个包含键，另一个包含它们的值。指数对应 (1:1,2:2)

keys = []
values = []

我需要使用字典生成器创建字典，其中的键是keys[i]，值是values[i]。

告诉我这个动作的正确语法，到目前为止发生的一切：

{k:v for k in keys for v in values} 

但是，此语法会创建一个嵌套列表并完全遍历它。
我可以以某种方式实现从列表中获取同步数据吗？

我有 4 个函数可以计算年/天/小时/分钟的数量，具体取决于输入的秒数。

def how_mc_m_in_seconds(seconds):
    """The function returns value of 
    minutes in inputed seconds"""
    if seconds // SEC_IN_MINUTE > 0:
        minutes = seconds // SEC_IN_MINUTE
        seconds = seconds - (minutes * SEC_IN_MINUTE)
        return seconds, minutes
    return seconds

我有 SEC_IN_MINUTE/HOUR/DAY/YEAR 常量，我不对它们执行任何操作，但在错误日志中我收到一个通知，指出元组不支持 // 操作，尽管它不是元组，而是一个整数。

除了常量和计数器的替换之外，所有功能都与提供的功能相同

format_duration(3600)

也许函数调用中的错误？