无法将用户序列化程序导入到其他 serializers.py

Question

我一直没能弄清楚这一点。

我正试图从"accounts"应用程序导入我的UserSerializer（），这样我就可以在"comments"应用程序的CommentSerializer）中使用它。

如果我尝试嵌套另一个序列化程序，比如"点赞"应用程序中的LikeSerializer（），就没有问题。

如果您在comments.serializers.py中注意到，我可以取消对LikeSerializer部分的注释，并对UserSerializer进行注释，不会出现任何错误。

但一旦我取消对UserSerializer（）的注释，就会遇到ImportError: cannot import name UserSerializer。

我的文件夹结构：

/apps
  /accounts
    serializers.py
  /comments
    serializers.py

**accounts.seriers.py

from django.contrib.auth import update_session_auth_hash
from rest_framework import serializers
from .models import User, ProfilePic
from ..memories.serializers import MemorySerializer
class UserSerializer(serializers.ModelSerializer):
    memories = MemorySerializer(many=True,read_only=True)
    password = serializers.CharField(write_only=True, required=False)
    # password2 = serializers.CharField(write_only=True, required=False)
    class Meta:
        model = User
        fields = ('id', 'email', 'first_name', 'last_name', 'created_at', 'relation', 'password', 'memories',)
        read_only_fields = ('created_at',)
        def create(self, validated_data):
            return User.objects.create_user(**validated_data)
        def update(self, instance, validated_data):
            instance.email = validated_data.get('email', instance.email)
            instance.first_name = validated_data.get('first_name', instance.first_name)
            isntance.last_name = validated_data.get('last_name', instance.last_name)
            instance.relation = validated_data.get('relation', instance.relation)
            instance.save()
            password = validated_data.get('password', instance.password)
            # password2 = validated_data.get('password2', instance.password2)
            # if password and password2 and password == password2:
            #   instance.set_password(password)
            #   instance.save()
            update_session_auth_hash(self.context.get('request'), instance)
            return instance

**评论.serializers.py

from .models import Comment
from ..accounts.serializers import UserSerializer
# from ..likes.serializers import LikeSerializer
from rest_framework import serializers
class CommentSerializer(serializers.ModelSerializer):
    author = UserSerializer()   
    # likes = LikeSerializer(many=True,read_only=True)
    # sub_comments = serializers.CommentSerializer()
    class Meta:
        model = Comment
        fields = ('id','author','memory','content','sub_comments', 'likes','created_at')
        read_only = ('memory','created_at',)
        depth = 1

**回溯

Unhandled exception in thread started by <function wrapper at 0x1037e1cf8>
Traceback (most recent call last):
  File "/Users/bchuey/.environments/dm_lin/lib/python2.7/site-packages/django/utils/autoreload.py", line 226, in wrapper
    fn(*args, **kwargs)
  File "/Users/bchuey/.environments/dm_lin/lib/python2.7/site-packages/django/core/management/commands/runserver.py", line 116, in inner_run
    self.check(display_num_errors=True)
  File "/Users/bchuey/.environments/dm_lin/lib/python2.7/site-packages/django/core/management/base.py", line 426, in check
    include_deployment_checks=include_deployment_checks,
  File "/Users/bchuey/.environments/dm_lin/lib/python2.7/site-packages/django/core/checks/registry.py", line 75, in run_checks
    new_errors = check(app_configs=app_configs)
  File "/Users/bchuey/.environments/dm_lin/lib/python2.7/site-packages/django/core/checks/urls.py", line 13, in check_url_config
    return check_resolver(resolver)
  File "/Users/bchuey/.environments/dm_lin/lib/python2.7/site-packages/django/core/checks/urls.py", line 23, in check_resolver
    for pattern in resolver.url_patterns:
  File "/Users/bchuey/.environments/dm_lin/lib/python2.7/site-packages/django/utils/functional.py", line 33, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "/Users/bchuey/.environments/dm_lin/lib/python2.7/site-packages/django/core/urlresolvers.py", line 417, in url_patterns
    patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)
  File "/Users/bchuey/.environments/dm_lin/lib/python2.7/site-packages/django/utils/functional.py", line 33, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "/Users/bchuey/.environments/dm_lin/lib/python2.7/site-packages/django/core/urlresolvers.py", line 410, in urlconf_module
    return import_module(self.urlconf_name)
  File "/usr/local/Cellar/python/2.7.11/Frameworks/Python.framework/Versions/2.7/lib/python2.7/importlib/__init__.py", line 37, in import_module
    __import__(name)
  File "/Users/bchuey/Documents/digital_memorials/dm_you_lin/src/digital_memorial/urls.py", line 19, in <module>
    from apps.accounts.views import UserViewSet, ProfilePicViewSet, LoginView
  File "/Users/bchuey/Documents/digital_memorials/dm_you_lin/src/apps/accounts/views.py", line 5, in <module>
    from .serializers import UserSerializer, ProfilePicSerializer
  File "/Users/bchuey/Documents/digital_memorials/dm_you_lin/src/apps/accounts/serializers.py", line 5, in <module>
    from ..memories.serializers import MemorySerializer
  File "/Users/bchuey/Documents/digital_memorials/dm_you_lin/src/apps/memories/serializers.py", line 3, in <module>
    from ..comments.serializers import CommentSerializer
  File "/Users/bchuey/Documents/digital_memorials/dm_you_lin/src/apps/comments/serializers.py", line 4, in <module>
    from ..accounts.serializers import UserSerializer
ImportError: cannot import name UserSerializer

Answer 1

将"apps"文件夹附加到您的python路径并尝试从accounts.serializers导入？您也可以删除所有前导。。从您的其他导入（如果它们是应用程序的子目录）

**accounts.seriers.py

import sys
sys.path.append("/Users/bchuey/Documents/digital_memorials/dm_you_lin/src/apps") 
from django.contrib.auth import update_session_auth_hash
from rest_framework import serializers
from .models import User, ProfilePic
from memories.serializers import MemorySerializer
class UserSerializer(serializers.ModelSerializer):
    memories = MemorySerializer(many=True,read_only=True)
    password = serializers.CharField(write_only=True, required=False)
    password2 = serializers.CharField(write_only=True, required=False)
    class Meta:
        model = User
        fields = ('id', 'email', 'first_name', 'last_name', 'created_at', 'relation', 'password', 'memories',)
        read_only_fields = ('created_at',)
        def create(self, validated_data):
            return User.objects.create_user(**validated_data)
        def update(self, instance, validated_data):
            instance.email = validated_data.get('email', instance.email)
            instance.first_name = validated_data.get('first_name', instance.first_name)
            instance.last_name = validated_data.get('last_name', instance.last_name)
            instance.relation = validated_data.get('relation', instance.relation)
            instance.save()
            password = validated_data.get('password', instance.password)
            password2 = validated_data.get('password2', instance.password2)
            if password and password2 and password == password2:
                instance.set_password(password)
                instance.save()
            update_session_auth_hash(self.context.get('request'), instance)
            return instance

**评论.serializers.py

import sys
sys.path.append("/Users/bchuey/Documents/digital_memorials/dm_you_lin/src/apps") 
from .models import Comment
from accounts.serializers import UserSerializer
from likes.serializers import LikeSerializer
from rest_framework import serializers
class CommentSerializer(serializers.ModelSerializer):
    author = UserSerializer()   
    likes = LikeSerializer(many=True,read_only=True)
    sub_comments = serializers.CommentSerializer()
    class Meta:
        model = Comment
        fields = ('id','author','memory','content','sub_comments', 'likes','created_at')
        read_only = ('memory','created_at',)
        depth = 1