Django Rest框架外键序列化

我有以下型号：

class Geofence(models.Model):
    id = models.IntegerField(default=0, primary_key=True)
    name = models.CharField(max_length=200, default="Geofence", blank=False)
    lat = models.DecimalField(default=0, decimal_places=6, max_digits=10, blank=False)
    long = models.DecimalField(default=0, decimal_places=6, max_digits=10, blank=False)
    radius = models.IntegerField(default=10, blank=False)

    def __str__(self):
        return "Geofence: " + str(self.name);

class Checkpoint(models.Model):
    id = models.IntegerField(default=0, primary_key=True)
    name = models.CharField(max_length=200, default="Geofence", blank=False)
    geofence = models.ForeignKey(Geofence, related_name='geofence')
    lat = models.DecimalField(default=0, decimal_places=6, max_digits=10, blank=False)
    long = models.DecimalField(default=0, decimal_places=6, max_digits=10, blank=False)
    trip_id = models.IntegerField(default=0, blank=False)
    enter_time = models.DateTimeField("Enter Time", blank=False)
    start_time = models.DateTimeField("Start Time", blank = True, null=True)
    stop_time = models.DateTimeField("Stop Time", blank= True, null = True)

以及它们各自的序列化程序：

class GeofenceSerializer(serializers.ModelSerializer):
    id = serializers.IntegerField(min_value=0)
    name = serializers.CharField()
    lat = serializers.DecimalField(max_digits=10, decimal_places=6, coerce_to_string=False)
    long = serializers.DecimalField(max_digits=10, decimal_places=6, coerce_to_string=False)
    radius = serializers.IntegerField(min_value=0)
    class Meta:
        model = Geofence
        fields = ('id', 'name','lat', 'long', 'radius')

    def create(self, valid_data):
        return Geofence.objects.create(**valid_data)

    def update(self, instance, valid_data):
        instance.id = valid_data.get('id', instance.id)
        instance.name = valid_data.get('name', instance.name)
        instance.name = valid_data.get('lat', instance.lat)
        instance.long = valid_data.get('long', instance.long)
        instance.radius = valid_data.get('radius', instance.radius)
        instance.save()



class CheckpointSerializer(serializers.ModelSerializer):
    lat = serializers.DecimalField(max_digits=10, decimal_places=6, coerce_to_string=False)
    long = serializers.DecimalField(max_digits=10, decimal_places=6, coerce_to_string=False)
    enter_time = serializers.DateTimeField()
    start_time =serializers.DateTimeField()
    geofence = serializers.SlugRelatedField(many=False, slug_field="id", read_only=True)
    class Meta:
        model = Checkpoint
        fields = ('trip_id', 'geofence', 'start_time', 'stop_time', 'lat', 'long', 'enter_time')

我从一个滑块中获取日期时间，并进行ajax调用以获取相关数据。服务器以500错误响应。具体来说，错误“KeyError:geofence”

这是一个称为：

class ResultsView(APIView):
    model = Checkpoint
    serializer_class = CheckpointSerializer
    def get(self, request, start, end):
        begin_date = parse_datetime(request.GET["start"]) 
        end_date = parse_datetime(request.GET["end"])
        ids = Checkpoint.objects.filter(start_time__range=(begin_date,end_date)).filter(stop_time__range=(begin_date,end_date)).distinct().values('trip_id', 'lat', 'long', 'enter_time')
        serializer = CheckpointSerializer(ids, many=True)
        return Response(serializer.data)

    def post(self, request, format=None):
        request.data["id"] = uuid.uuid4().int & (1<<8)-1
        serializer = CheckpointSerializer(data= request.data)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data)
        return Response(serializer.error)

我认为问题在于序列化程序中的外键：

geofence = serializers.SlugRelatedField(many=False, slug_field="id", read_only=True)

---

这是在django rest框架中序列化外键的正确方法吗？如果没有，有人能举个例子吗？

我想你必须做一些改变。您可以在GeofenceSerializer中引入许多检查点。这样：

class GeofenceSerializer(serializers.ModelSerializer):
      id = serializers.IntegerField(min_value=0)
      name = serializers.CharField()
      lat = serializers.DecimalField(max_digits=10, decimal_places=6,     coerce_to_string=False)
      long = serializers.DecimalField(max_digits=10, decimal_places=6, coerce_to_string=False)
      radius = serializers.IntegerField(min_value=0)
      checkpoint = serializers.PrimaryKeyRelatedField(many=True, read_only=True)
      class Meta:
           model = Geofence
          fields = ('id', 'name','lat', 'long', 'radius','checkpoint')

def create(self, valid_data):
    return Geofence.objects.create(**valid_data)

def update(self, instance, valid_data):
    instance.id = valid_data.get('id', instance.id)
    instance.name = valid_data.get('name', instance.name)
    instance.name = valid_data.get('lat', instance.lat)
    instance.long = valid_data.get('long', instance.long)
    instance.radius = valid_data.get('radius', instance.radius)
    instance.save()



class CheckpointSerializer(serializers.ModelSerializer):
      lat = serializers.DecimalField(max_digits=10, decimal_places=6, coerce_to_string=False)
      long = serializers.DecimalField(max_digits=10, decimal_places=6, coerce_to_string=False)
      enter_time = serializers.DateTimeField()
      start_time =serializers.DateTimeField()

      class Meta:
           model = Checkpoint
           fields = ('trip_id', 'start_time', 'stop_time', 'lat', 'long', 'enter_time') 

---

对于这个特殊问题，我通过在字符字段中使用源参数来表示外键，而不是相关字段来解决它。在这种情况下，正确的序列化程序条目是：

geofence = serializers.CharField(source='geofence.id', read_only=True)

class Meta:
    model = Checkpoint
    fields = ('geofence', 'start_time', 'lat', 'long', 'enter_time')

我在Checkpoint表中使用它，因为Checkpoint是一个地理围栏，而不是将外键错误地放在原始post的地理围栏表中。字段名仅列在meta类中。类元是必需的，因为序列化程序是模型序列化程序。

您的意思是

有一个简单的例子：

class AccountSerializer(serializers.ModelSerializer):
    class Meta:
        model = Account
        depth = 1 # You need only add this sentence.

结果是这样的：

[
  {
    "id": 1,
    "priority": 10,
    "role": {
      "id": 1,
      "department": "researcher"
    }
  }
]

---

但是，您可以获得ForeignKey的所有字段。我不知道如何获得ForeignKey的某些字段。

老实说，我突然想到，我的问题可能不是我最初认为的问题。不过，这很有帮助，我会将其标记为答案。Depth=1适合我。这扩展了所有相关模型。

[
  {
    "id": 1,
    "priority": 10,
    "role": {
      "id": 1,
      "department": "researcher"
    }
  }
]