python - Django Rest 中的序列化器不返回关系对象

Question

我有 4 个模型，其中一个是其他三个之间的关系。序列化器也是如此。

但是当我从 API 检索数据时，我没有收到所有数据，我只收到字段“天”、“订单”和“时间”，而不是“教师”、“主题”和“在 ScheduleClassTeacherSubjectSerializer

上声明的 in_class' 字段

型号:

class User(models.Model):
    name = models.CharField(max_length=20, unique=True, blank=False, null=False)

class Subject(models.Model):
    name = models.CharField(max_length=20, unique=True, blank=False, null=False)

class Class(models.Model):
    name = models.CharField(max_length=20, unique=True, blank=False, null=False)

class ClassTeacherSubject(models.Model):
    teacher = models.ForeignKey(User,
                                related_name='classes_subjects',
                                on_delete=models.CASCADE,
                                null=False,
                                blank=False,
                                )
    subject = models.ForeignKey(Subject,
                                related_name='classes_teachers',
                                on_delete=models.CASCADE,
                                null=False,
                                blank=False,
                                )
    teaches_in = models.ForeignKey(Class,
                                   related_name='teachers_subjects',
                                   on_delete=models.CASCADE,
                                   null=False,
                                   blank=False,
                                   )

class Schedule(models.Model):
    MONDAY = 'MONDAY'
    TUESDAY = 'TUESDAY'
    WEDNESDAY = 'WEDNESDAY'
    THURSDAY = 'THURSDAY'
    FRIDAY = 'FRIDAY'

    DAY_CHOICES = (
        (MONDAY, 'Monday'),
        (TUESDAY, 'Tuesday'),
        (WEDNESDAY, 'Wednesday'),
        (THURSDAY, 'Thursday'),
        (FRIDAY, 'Friday'),
    )

    ORDER = (
        (1, 1),
        (2, 2),
        (3, 3),
        (4, 4),
        (5, 5),
        (6, 6),
        (7, 7),
        (8, 8),
        (9, 9),
        (10, 10),
    )

    day = models.CharField(max_length=10,
                           choices=DAY_CHOICES,
                           null=False,
                           blank=False
                           )

    order = models.IntegerField(choices=ORDER,
                                null=False,
                                blank=False)

    time = models.TimeField(null=True,
                            blank=True,
                            )

    class_teacher_subject = models.ForeignKey(ClassTeacherSubject,

                                              on_delete=models.CASCADE,
                                              null=False,
                                              blank=False,
                                              )

    class Meta:
        unique_together = ('day', 'order', 'class_teacher_subject')

序列化器:

class TeacherSerializer(serializers.ModelSerializer):
    class Meta:
        model = User
        fields = ('id', 'name',)

class SubjectSerializer(serializers.ModelSerializer):
    class Meta:
        model = Subject
        fields = ('id', 'name',)

class ClassSerializer(serializers.ModelSerializer):
    class Meta:
        model = Class
        fields = ('id',
                  'name')

class ScheduleClassTeacherSubjectSerializer(serializers.HyperlinkedModelSerializer):
    teacher = TeacherSerializer(read_only=True)
    subject = SubjectSerializer(read_only=True)
    in_class = ClassSerializer(read_only=True)

    class Meta:
        model = User
        fields = ('teacher',
                  'subject',
                  'in_class',
                  )

class ScheduleSerializer(serializers.HyperlinkedModelSerializer):
    schedule_class_teacher_subject = ScheduleClassTeacherSubjectSerializer(read_only=True)

    class Meta:
        model = Schedule
        fields = (
            'day',
            'order',
            'time',
            'schedule_class_teacher_subject',
        )

Answer 1

尝试将 ScheduleSerializer 中的 schedule_class_teacher_subject 替换为 class_teacher_subject。