API 端点返回 TypeError: 'type' object is not iterable答案

【问题标题】：API endpoint returns TypeError: 'type' object is not iterableAPI 端点返回 TypeError: 'type' object is not iterable
【发布时间】：2020-06-20 14:12:57
【问题描述】：

我正在通过使用AbstractBaseUser 类扩展users 类来编写创建用户API。该 API 对常规 model fields 工作正常，例如 EmailField、CharField、BooleanField。但后来我决定也存储用户的profile_picture。所以我创建了一个新字段profile_picture 为ImageField 来将用户头像的路径存储在相同的扩展users 模型中。

models.py

class Users(AbstractBaseUser, PermissionsMixin):

    """
    This model is used to store user login credential and profile information.
    It's a custome user model but used for Django's default authentication.
    """

    email = models.EmailField(max_length=255, unique=True)
    first_name = models.CharField(max_length=255, blank=False, null=False)
    last_name = models.CharField(max_length=255, blank=False, null=False)
    profile_picture = models.ImageField(upload_to='Images/', max_length=None, blank=True)
    is_active = models.BooleanField(default=True)

    # defing a custome user manager class for the custome user model.
    objects = managers.UserManager()

    # using email a unique identity for the user and it will also allow user to use email while logging in.
    USERNAME_FIELD = 'email'

然后我更新了UserAPIView 类以添加parser_classes = (FileUploadParser)

view.py

from django.shortcuts import render
from . import views
from rest_framework.views import APIView
from django.db import IntegrityError
from rest_framework import status
from . import models, serializers
from rest_framework.response import Response
from django.core.mail import send_mail
from rest_framework.parsers import FileUploadParser



class UserAPIViews(APIView):
    """
    """

    parser_classes = (FileUploadParser)

    def post(self, request, format=None):
        """
        """
        print(request.data)
        serialized_data = serializers.UserSerializer(data=request.data)
        if serialized_data.is_valid():

            try:
                user_id = serialized_data.save()
            except IntegrityError as error:
                message = f"Email already exist."
                return Response ({
                    'error_message' : message,
                    'status' : status.HTTP_226_IM_USED
                })

            subject = 'Eitan - Case Manager Account Credentials'
            body = f"Hi {serialized_data.validated_data.get('first_name')} Your case manager account is ready. Please use following credentials to login. Email - {serialized_data.validated_data.get('email')}, Password - {serialized_data.validated_data.get('password')} Thank You! Team Eitan."
            sender = "steinnlabs@gmail.com"
            to = serialized_data.validated_data.get('email')

            send_mail(subject, body, sender, [to], fail_silently=False)

            success_message = f"User has been created."

            return Response({
                'success_message' : success_message,
                'status' : status.HTTP_201_CREATED
            })

        else:
            return Response (serialized_data.error_messages)

更新settings.py 以添加MEDIA_ROOT 和MEDIA_URL

settings.py

# Image upload configurations
MEDIA_ROOT = os.path.join(BASE_DIR, "media")
MEDIA_URL = '/media/

现在，当我尝试到达http://127.0.0.1:8000/user/create/ 的终点时，它会返回 -

TypeError at /user/create/
'type' object is not iterable

【问题讨论】：

标签： python django

【解决方案1】：

parser_classes = (FileUploadParser)

应该是

parser_classes = (FileUploadParser,)

或者使用列表[] 代替元组。

如果不添加逗号，Python 会以与 x = something 相同的方式解释 x = (something)。

【讨论】：

现在返回{ "detail": "Missing filename. Request should include a Content-Disposition header with a filename parameter." }
这是一个不同的错误。你问的那个已经解决了！请查看stackoverflow.com/questions/46806335/…
你能告诉我如何将请求传递给 URL http://127.0.0.1:8000/user/create/。我以前从未创建过图像上传 API。我的 JSON 对象中没有t know how to send the JSON request to upload files. Do I have to mention the path of image file as a value to key profile_picture`？
您可以使用表单并通过request.FILES 获取内容。见：stackoverflow.com/questions/20822823/…

【解决方案2】：

我只需要添加解析器类来解析request.data。

parser_classes = (FormParser, MultiPartParser)

【讨论】：