Question

我收到错误

AttributeError: Got AttributeError when attempting to get a value for field `status_code` on serializer `MedTestGetTestResultSerializer`.
The serializer field might be named incorrectly and not match any attribute or key on the `unicode` instance.
Original exception text was: 'unicode' object has no attribute 'status_code'.

当我尝试编写Django序列化程序时。

我的序列化器看起来像这样：

class MedTestGetTestSerializer(serializers.ModelSerializer):
    test_id = serializers.CharField(source='medteststypetest_id.test_id')
    test_name = serializers.CharField(source='medteststypetest_id.test_name')
    username = serializers.CharField(source='user_id.username')
    user_id = serializers.CharField(source='user_id.user_id')
    kit_id = serializers.CharField(source='kit_id.kit_id')
    test_results = MedTestGetTestResultSerializer(source='medtests_id', many=True, required=False)

class Meta:
    model = MedTests
    fields = ("medtests_id",
              "datekitord",
              "testdate",
              "user_id",
              "kit_id",
              "status",
              "username",
              "test_name",
              "test_id",
              "test_results")

我的嵌套序列化程序如下所示：

class MedTestGetTestResultSerializer(serializers.ModelSerializer):
    class Meta:
        model = MedTestsResults
        fields = ("result_date",
                  "value",
                  "test_started",
                  "status_code")

为什么我会收到此错误？当我尝试在shell中使用第二个序列化程序时，当我没有设置many = True时，我得到status_code错误，但是我在第一个序列化程序中设置了many = True。

MedTestsResults模型：

class MedTestsResults(models.Model):
    medtests_results_id = models.CharField(max_length=100)
    medtests_id = models.ForeignKey(MedTests)
    result_date = models.DateTimeField(null=True, blank=True)
    test_started = models.DateTimeField(null=True, blank=True)
    status_code = models.CharField(max_length=25)
    value = models.IntegerField(null=True, blank=True)
    hiv4g_rsltdate = models.DateTimeField(null=True, blank=True)
    hivms_rsltdate = models.DateTimeField(null=True, blank=True)
    hiv4gpos = models.CharField(max_length=100, null=True, blank=True)
    hiv4gneg = models.CharField(max_length=100, null=True, blank=True)
    hiv4gind = models.CharField(max_length=100, null=True, blank=True)
    hiv4grej = models.CharField(max_length=100, null=True, blank=True)
    hivmpos = models.CharField(max_length=100, null=True, blank=True)
    hivmsneg = models.CharField(max_length=100, null=True, blank=True)
    hivmsind = models.CharField(max_length=100, null=True, blank=True)
    hivmsrej = models.CharField(max_length=100, null=True, blank=True)

MedTests：

class MedTests(models.Model):
    medtests_id = models.CharField(max_length=100)
    medteststypetest_id = models.ForeignKey(MedTestsType)
    datekitord = models.DateTimeField()
    testdate = models.DateTimeField()
    status = models.CharField(max_length=100)
    hiv4g_testdate = models.DateTimeField(blank=True, null=True)
    hivms_testdate = models.DateTimeField(blank=True, null=True)
    kit_id = models.ForeignKey(Kits)
    user_id = models.ForeignKey(User)

Answer 1

回答：使用related_name attr

models.py

class MedTest(models.Model):
    date_kit_ord = models.DateTimeField()
    test_date = models.DateTimeField()
    status = models.CharField(max_length=100)
    hiv4g_test_date = models.DateTimeField(blank=True, null=True)
    hivms_test_date = models.DateTimeField(blank=True, null=True)
    user = models.ForeignKey(User)

class MedTestResult(models.Model):
    med_test_result = models.CharField(max_length=100)
    med_test = models.ForeignKey(MedTest, related_name='med_tests')
    result_date = models.DateTimeField(null=True, blank=True)
    test_started = models.DateTimeField(null=True, blank=True)
    status_code = models.CharField(max_length=25)
    value = models.IntegerField(null=True, blank=True)
    hiv4g_rsltdate = models.DateTimeField(null=True, blank=True)
    hivms_rsltdate = models.DateTimeField(null=True, blank=True)
    hiv4gpos = models.CharField(max_length=100, null=True, blank=True)
    hiv4gneg = models.CharField(max_length=100, null=True, blank=True)
    hiv4gind = models.CharField(max_length=100, null=True, blank=True)
    hiv4grej = models.CharField(max_length=100, null=True, blank=True)
    hivmpos = models.CharField(max_length=100, null=True, blank=True)
    hivmsneg = models.CharField(max_length=100, null=True, blank=True)
    hivmsind = models.CharField(max_length=100, null=True, blank=True)
    hivmsrej = models.CharField(max_length=100, null=True, blank=True)

tracing.py

import os
import django

os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'youproject.settings')

django.setup()

from rest_framework import serializers

from frontend import models as fm

class MedTestResultSerializer(serializers.ModelSerializer):
    class Meta:
        model = fm.MedTestResult
        fields = ('result_date',
                  'value',
                  'test_started',
                  'status_code')

class MedTestSerializer(serializers.ModelSerializer):
    username = serializers.CharField(source='user.username')
    user_id = serializers.CharField(source='user.id')
    med_tests = MedTestResultSerializer(many=True)

    class Meta:
        model = fm.MedTest
        fields = (
            'med_tests',
            'user_id',
            'username',
        )


print MedTestSerializer(fm.MedTest.objects.all()[0]).data

非常难以阅读代码（样式，命名约定等），请尝试two scoops

Answer 2

我认为django-rest-framework在某处使用status_code，您可能想尝试将status_code字段重命名为其他字段。

Answer 3

在我看来，问题可能出现在视图中。如果您在视图中定义错误的queryset，则会收到此错误。例如

class YourViewSet(ModelViewSet):
    queryset = WrongModel.objects.all()
    serializer_class = YourSerializer

如果您为queryset值使用的模型与序列化程序中定义的模型不同，则会收到该错误。

尝试获取字段'status_code'的值时出现AttributeError

3 个答案: