我正在构建微服务，我在仓库中有2个项目/1个数据库，在商店中有1个数据库。当我在仓库里有一本新书时，我在商店里更新了数据库——芹菜承担了这项任务

模型在仓库和商店一样。

我遇到了一个奇怪的错误，我找不到相关信息。

模型：

from django.db import models
from django.urls import reverse


class Author(models.Model):
    first_name = models.CharField(max_length=50)
    last_name = models.CharField(max_length=50)

    def __str__(self):
        return f'{self.first_name} {self.last_name}'


class Genre(models.Model):
    name = models.CharField(max_length=50, db_index=True)
    slug = models.SlugField(max_length=50, unique=True)

    class Meta:
        ordering = ('name',)
        verbose_name = 'genre'
        verbose_name_plural = 'genres'

    def __str__(self):
        return self.name

    def get_absolute_url(self):
        return reverse('shop:book_list_by_genre', args=[self.slug])


class Book(models.Model):
    author = models.ForeignKey('Author', on_delete=models.CASCADE)
    genre = models.ForeignKey(Genre,
                              related_name='books',
                              on_delete=models.CASCADE)
    title = models.CharField(max_length=255)
    description = models.TextField(blank=True)
    language = models.CharField("language", max_length=20)
    pages = models.IntegerField()
    image = models.ImageField(upload_to='products/%Y/%m/%d')
    slug = models.SlugField(max_length=255)
    price = models.DecimalField(max_digits=10, decimal_places=2)

    isbn = models.CharField('ISBN', max_length=13,
                            unique=True)
    created = models.DateTimeField(auto_now_add=True)
    available = models.BooleanField(default=True)
    quantity = models.IntegerField()

    class Meta:
        ordering = ('title',)
        index_together = (('id', 'slug'),)

    def __str__(self):
        return self.title

    def get_absolute_url(self):
        return reverse('shop:book_detail',
                       args=[self.id, self.slug])

芹菜：

from celery import shared_task

from django.core.mail import send_mail

import requests

from .models import Author, Book, Genre


@shared_task
def send_mail_task(subject, message, email):
    send_mail(subject, message, email, ['admin@example.com'])


@shared_task
def shop_sync():
    print('Starting update from warehouse api for database')
    print('Getting data from api...')

    url = 'http://warehouse:8001/warehouse/authors/'
    print('Clearing data...')

    response_author = requests.get(url)
    if response_author.status_code != 200:
        return
    response_data_author = response_author.json()
    while 1:
        for counter, data in enumerate(response_data_author['results']):
            Author.objects.get_or_create(
                id=data['id'],
                defaults={
                    'id': data['id'],
                    'first_name': data['first_name'],
                    'last_name': data['last_name']
                }
            )

        if response_data_author['next']:
            response_data_author = requests.get(response_data_author['next']).json()
        else:
            break

    url = 'http://warehouse:8001/warehouse/genres/'
    print('Clearing data...')

    response_genre = requests.get(url)
    if response_genre.status_code != 200:
        return
    response_data_genre = response_genre.json()

    while 1:
        for counter, data in enumerate(response_data_genre['results']):
            Genre.objects.get_or_create(
                id=data['id'],

                defaults={
                    'slug': data['slug'],
                    'name': data['name'],
                }
            )

        if response_data_genre['next']:
            response_data_genre = requests.get(
                response_data_genre['next']
            ).json()
        else:
            break

    url = 'http://warehouse:8001/warehouse/books/'
    print('Clearing data...')

    response_book = requests.get(url)
    if response_book.status_code != 200:
        return
    response_data_book = response_book.json()
    while 1:
        for counter, data in enumerate(response_data_book['results']):
            book, created = Book.objects.get_or_create(
                id=data['id'],
                defaults={
                    'id': data['id'],
                    "title": data['title'],
                    "description": data['description'],
                    "language": data['language'],
                    "pages": data['pages'],
                    "image": data['image'],
                    'slug': data['slug'],
                    "price": data['price'],
                    "isbn": data['isbn'],
                    "created": data['created'],
                    "available": data['available'],
                    "quantity": data['quantity'],
                    "author": Author.objects.get(id=data['author'])
                }
            )

            if not created:
                book.title = data['title']
                book.description = data['description']
                book.language = data['language']
                book.pages = data['pages']
                book.image = data['image']
                book.slug = data['slug']
                book.price = data['price']
                book.isbn = data['isbn']
                book.created = data['created']
                book.available = data['available']
                book.quantity = data['quantity']
                book.author = Author.objects.get(id=data['author'])
                book.save()

            for i in data['genre']:
                genre = Genre.objects.get(id=i)
                book.genre.add(genre)

        if response_data_book['next']:
            response_data_book = requests.get(response_data_book['next']).json()
        else:
            break
        print('Database was updated from warehouse api')

回溯：

-

回溯（最近一次调用）：文件“/usr/local/lib/python3.10/site packages/芹菜/app/trace.py”，行
450，在trace_task R=retval=fun（*args，**kwargs）文件“/usr/local/lib/python3.10/site packages/芹菜/app/trace.py”，行
731，在protected_调用返回self中。运行（*args，**kwargs）文件“/code/shop/tasks.py”，第78行，在shop\u sync book中，created=book。物体。获取或创建（文件“/usr/local/lib/python3.10/site packages/django/db/models/manager.py”，第85行，在manager\u方法中返回getattr（self.get\u queryset（），name）（*args，**kwargs）文件“/usr/local/lib/python3.10/site packages/django/db/models/query.py”，
第588行，在获取或创建返回self中。在create obj中创建（**params），真文件“/usr/local/lib/python3.10/site packages/django/db/models/query.py”，
第453行。保存（force_insert=True，using=self.db）文件“/usr/local/lib/python3.10/site packages/django/db/models/base.py”，第726行，保存到save self中。保存库（using=using，force\u insert=force\u insert，File）/usr/local/lib/python3.10/site packages/django/db/models/base.py“，
第763行，保存库更新=self.\u保存表（File）/usr/local/lib/python3.10/site packages/django/db/models/base.py“，
第868行，保存结果=self.\u插入（cls._base_manager，using，fields，returning_fields，raw）文件“/usr/local/lib/python3.10/site packages/django/db/models/base.py”，第906行，插入return manager_插入（文件“/usr/local/lib/python3.10/site packages/django/db/models/manager.py”，第85行，在manager_方法中返回getattr（self.get_queryset（），name）（*args，**kwargs）文件“/usr/local/lib/python3.10/site packages/django/db/models/query.py”，插入返回查询中的第1270行。获取编译器（使用=使用）。在execute_sql游标的第1416行执行_sql（返回_字段）文件“/usr/local/lib/python3.10/site packages/django/db/models/sql/compiler.py”。执行（sql，params）文件“/usr/local/lib/python3.10/site packages/django/db/backends/utils.py”，第98行，在execute return super（）中。执行（sql，params）文件“/usr/local/lib/python3.10/site packages/django/db/backends/utils.py”，执行返回self中的第66行_使用包装器执行（sql，params，many=False，executor=self.\u execute）文件“/usr/local/lib/python3.10/site packages/django/db/backends/utils.py”，第75行，使用包装器执行返回执行器（sql，params，many，context）文件“/usr/local/lib/python3.10/site packages/django/db/backends/utils.py”，第79行，使用self执行。db。包装数据库错误：文件“/usr/local/lib/python3.10/site packages/django/db/utils.py”，行
90，在出口处提升dj_exc_值。使用exc_值文件“/usr/local/lib/python3.10/site packages/django/db/backends/utils.py”第84行中的“traceback（traceback）”。光标。执行（sql，params）django。db。乌提尔斯。IntegrityError:relation“shop_book”的“genre_id”列中的空值违反了非空约束详细信息：失败的行包含（7，地狱，发现自己身处最神秘的意大利小镇佛罗伦萨，…，英语，472，
http://warehouse:8001/media/products/2021/09/15/cover-50.jpg，
inferno，445.0097803077369252021-10-1923:38:08.91029900，t，8，
1，null）。