已知：项目表、接口表、用例表，3表之间的关系

项目表与接口表的映射关系为一对多
接口表和用例表的映射关系为一对多

模型类如下：

项目模块

from django.db import models
from utils.base_models import BaseModel

class Projects(BaseModel):
    name = models.CharField('项目名称', max_length=200, unique=True, help_text='项目名称')
    leader = models.CharField('负责人', max_length=50, help_text='项目负责人')
    tester = models.CharField('测试人员', max_length=50, help_text='项目测试人员')
    programmer = models.CharField('开发人员', max_length=50, help_text='开发人员')
    publish_app = models.CharField('发布应用', max_length=100, help_text='发布应用')
    desc = models.CharField('简要描述', max_length=200, null=True, blank=True, default='', help_text='简要描述')

    class Meta:
        db_table = 'tb_projects'
        verbose_name = '项目信息'
        verbose_name_plural = verbose_name
        ordering = ('id',)

    def __str__(self):
        return self.name

接口模块

from django.db import models
from utils.base_models import BaseModel

class Interfaces(BaseModel):
    name = models.CharField('接口名称', max_length=200, unique=True, help_text='接口名称')
    project = models.ForeignKey('projects.Projects', on_delete=models.CASCADE,
                                related_name='interfaces', help_text='所属项目')
    tester = models.CharField('测试人员', max_length=50, help_text='测试人员')
    desc = models.CharField('简要描述', max_length=200, null=True, blank=True, help_text='简要描述')

    class Meta:
        db_table = 'tb_interfaces'
        verbose_name = '接口信息'
        verbose_name_plural = verbose_name
        ordering = ('id',)

    def __str__(self):
        return self.name

用例模块

from django.db import models
from django.db import models
from utils.base_models import BaseModel

class Testcases(BaseModel):
    name = models.CharField('用例名称', max_length=50, unique=True, help_text='用例名称')
    interface = models.ForeignKey('interfaces.Interfaces', on_delete=models.CASCADE,
                                  help_text='所属接口')
    include = models.TextField('前置', null=True, help_text='用例执行前置顺序')
    author = models.CharField('编写人员', max_length=50, help_text='编写人员')
    request = models.TextField('请求信息', help_text='请求信息')

    class Meta:
        db_table = 'tb_testcases'
        verbose_name = '用例信息'
        verbose_name_plural = verbose_name
        ordering = ('id',)

    def __str__(self):
        return self.name

需求：序列化输出项目名称、接口名称；反序列化输入项目id、接口id，序列化器怎么设计？

序列化器设计

from rest_framework import serializers

from interfaces.models import Interfaces
from projects.models import Projects
from testcases.models import Testcases
from utils.validators import ManualValidateExist

def test_pid(value):
    count = Projects.objects.filter(id=value).count()
    if not count:
        raise serializers.ValidationError('所传的项目id不存在')
    return value


def test_iid(value):
    count = Interfaces.objects.filter(id=value).count()
    if not count:
        raise serializers.ValidationError('所传的接口id不存在')
    return value


class InterfacesProjectsModelSerializer(serializers.ModelSerializer):
    project = serializers.StringRelatedField(label='接口所属项目', help_text='接口所属项目', read_only=True)
    pid = serializers.IntegerField(label='项目id',
                                   help_text='项目id',
                                   write_only=True,
                                   validators=[test_pid])
    iid = serializers.IntegerField(label='接口id',
                                   help_text='接口id',
                                   write_only=True,
                                   validators=[test_iid])


    class Meta:
        model = Interfaces
        fields = ['name', 'project', 'pid', 'iid']
        extra_kwargs = {
            'name': {
                'read_only': True
            }
        }

    def validate(self, attrs):
        resuit = Interfaces.objects.filter(id=attrs.get('iid'), project_id=attrs.get('pid')).exists()
        if not resuit:
            raise serializers.ValidationError('所属项目id和接口id不匹配')
        return attrs


class TestcasesModelSerializer(serializers.ModelSerializer):
    interface = InterfacesProjectsModelSerializer(help_text='用例所属接口', label='用例所属接口')

    class Meta:
        model = Testcases
        exclude = ['update_time', 'create_time']
        extra_kwargs = {
            'include': {
                "write_only": True
            },
            'request': {
                'write_only': True
            }
        }


    def to_internal_value(self, data):
        response=super().to_internal_value(data)
        iid = data.get('interface').get('iid')
        response['interface'] = Interfaces.objects.get(id=iid)
        return response


class TestcasesRunSerializer(serializers.ModelSerializer):
    env_id=serializers.IntegerField(label='所属环境配置id',help_text='所属环境配置uid',
                                    validators=[ManualValidateExist('env')])

    class Meta:
        model=Testcases
        fields=['id','env_id']