How to get data related from another table django rest framework

Question

I have three model Pesticide, Disease and Instruction what i want is to get all disease with relation to pesticide which relate to instruction model

class Disease(models.Model):
    name = models.CharField(max_length=100)
    def __str__(self):
        return self.name

class Pesticide(models.Model):
    name = models.CharField(max_length=50)
    def __str__(self):
        return self.name


class Treatment(models.Model):
    disease = models.ForeignKey(Disease, related_name='treatments', on_delete=models.DO_NOTHING)
    pesticide = models.ForeignKey(Pesticide, related_name='treatments', on_delete=models.DO_NOTHING)

    def __str__(self):
        return self.instruction

and serializer

class PesticideSerializer(serializers.ModelSerializer):
   
    class Meta:
        model = Pesticide
        fields = ('id', 'name')

class DiseaseSerializer(serializers.ModelSerializer):
    pesticides = PesticideSerializer(source='treatment_set', read_only=True)
    class Meta:
        model = Disease
        fields = [

            'id',
            'name',
            'pesticides',
           
        ]

My problem is that i can not get pesticides in django serializer

Answer 1

Use serializers.SerializerMethodField as

class DiseaseSerializer(serializers.ModelSerializer):
    

    class Meta:
        model = Disease
        fields = ['id', 'name', 'pesticides']

Answer 2

我认为将pesticides = PesticideSerializer(source='treatment_set', read_only=True) DiseaseSerializer的行pesticides = PesticideSerializer(source='treatment_set', read_only=True) DiseaseSerializer为pesticides = PesticideSerializer(source='treatment_set', read_only=True, many=True)将解决您的问题（您应该添加many=True因为关系类型是一对多）。