Unknown's questions

我想发出 POST 请求来创建机器人并传递多个经过 Base64 编码的 photo_examples 图像。默认情况下，使用Base64图像字段时，只能添加一张图像，但我需要添加几张。我尝试查看网上的其他项目，但没有找到解决方案，请问如何实现？

模型.py

class Bot(models.Model):
    """Bot Model."""
    name = models.CharField(
        'Название',
        max_length=100
    )
    author = models.ForeignKey(
        User,
        on_delete=models.CASCADE,
        verbose_name='Автор',
    )
    description = models.TextField(
        'Описание'
    )
    categories = models.ManyToManyField(
        Category,
        through='CategoryBot',
        related_name='bots',
        verbose_name='Категории',
    )
    main_photo = models.ImageField(
        'Фото',
        upload_to='uploads/main/%Y/%m/%d/',
    )
    price = models.DecimalField(
        'Цена',
        max_digits=8,
        decimal_places=0
    )
    is_special_offer = models.BooleanField(
        'Спецпредложение',
        default=False
    )

    class Meta:
        ordering = ('name',)
        verbose_name = 'Бот'
        verbose_name_plural = 'Боты'

    def __str__(self):
        return self.name


class Photo(models.Model):
    """Model of photos of examples of the bot's work."""
    photo_examples = models.ImageField(
        'Фото(образцы)',
        upload_to='uploads/examples/%Y/%m/%d/',
    )
    bot = models.ForeignKey(
        Bot,
        on_delete=models.CASCADE,
        verbose_name='Бот',
        related_name='photo_examples'
    )

    class Meta:
        ordering = ('bot',)
        verbose_name = 'Фото(образцы)'
        verbose_name_plural = 'Фото(образцы)'

    def __str__(self):
        return f' Фото бота {self.bot}'

序列化器.py

class PhotoSerializer(serializers.ModelSerializer):
    """Serializer of photo bot examples"""
    photo_examples = Base64ImageField()

    class Meta:
        model = Photo
        fields = '__all__'


class CategoryNameSerializer(serializers.PrimaryKeyRelatedField):
    def to_representation(self, value):
        return value.name


class AbstractBotSerializer(serializers.ModelSerializer):
    """
    An abstract class that defines serialization and
deserialization behavior for bot-related data.
    """
    photo_examples = PhotoSerializer(many=True)
    author = serializers.StringRelatedField(read_only=True)
    discount_author = serializers.SerializerMethodField()
    discount_category = serializers.SerializerMethodField()
    amount_discounts_sum = serializers.SerializerMethodField()
    final_price = serializers.SerializerMethodField()
    categories = CategoryNameSerializer(
        required=False,
        queryset=Category.objects.all(),
        many=True,
    )

    class Meta:
        abstract = True
        fields = '__all__'

视图.py

class BotViewSet(ModelViewSet):
    """The viewset for the bot.
    With the possibility of pagination, search by name
    and description, filtering by category"""
    queryset = Bot.objects.all()
    serializer_class = BotSerializer
    pagination_class = LimitPageNumberPagination
    filter_backends = (filters.SearchFilter, DjangoFilterBackend, )
    search_fields = ('name', 'description')
    permission_classes = (IsAuthorOrReadOnly, IsAuthor,)
    filterset_fields = ('categories', )

    def get_serializer_class(self):
        if self.action == 'retrieve':
            return BotReviewRatingSerializer
        return self.serializer_class

    def perform_create(self, serializer):
        discount_author = self.request.data.get("discount_author", 0)

        bot_instance = serializer.save(author=self.request.user)

        bot_discount, created = BotDiscount.objects.get_or_create(
            bot=bot_instance, defaults={"discount": discount_author}
        )

        if not created:
            bot_discount.discount = discount_author
            bot_discount.save()

我想以这种格式传递数据，但是如果有一种方法可以更轻松地实现添加多个图像，那么可以使用另一种传递多个图像的方法。

发布请求

{
    "name": "My Bot New",
    "description": "This is my bot",
    "main_photo": "data:image/jpeg;base64,/9j/4A....A/9k=",
    "price": 500,
    "discount_author": 35,
    "categories": [6, 4],
    "photo_examples": [
        {
        "photo_examples": "data:image/jpeg;base64,/9j/4A....A/9k="
        },
        {
        "photo_examples": "data:image/jpeg;base64,/9j/4A....A/9k="
        }
    ]
}

现在我收到此错误消息：

{
    "photo_examples": [
        {
            "bot": [
                "Required field"
            ]
        },
        {
            "bot": [
                "Required field."
            ]
        }
    ]
}

如果程序接收到 a = 0, b = 0, c - any 作为输入，则应用程序崩溃。错误出现在这一行if (c % gcd != 0)

public void print_solution(int a, int b, int c) {
            if (a == 0 && b == 0) {
                // Условие бесконечности решений
                if (c == 0) {
                    rezult.setText("x - любое число " +
                            System.getProperty("line.separator") + "y - любое число");
                }
                // Условие отсутствия решений
                else {
                    rezult.setText("Решений нет");
                }
            }

            int gcd = gcd_extend(a, b);
            // Условие отсутствия решений
            if (c % gcd != 0) {
                rezult.setText("Решений нет");
            } else {
                // Решение
                rezult.setText("x = " + x * (c / gcd) +
                        System.getProperty("line.separator") + "y = " + y * (c / gcd));
                }
            }

            int x, y;
            public int gcd_extend(int a, int b) {

                // Базовый вариант
                if (b == 0) {
                    x = 1;
                    y = 0;
                    return a;
                } else {
                    int g = gcd_extend(b, a % b);
                    int x1 = x, y1 = y;
                    x = y1;
                    y = x1 - (a / b) * y1;
                    return g;
                }
            }

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