django restful framework 一对多方向更新数据库

2021-11-28 16:37:19

django restful framework 序列化

django restful framework 序列化

案例: 一个网域domain可以绑定多台服务器主机assets, 但是一台服务器只能绑定一个网域. 数据模型之间关系适用于一对多.

一 . 数据模型: models

定义 assets 模型:apps/assets/models/asset.py

#!/usr/bin/env python

# -*- coding: utf-8 -*-

import uuid

from django.db import models

class Asset(models.Model):

    id = models.UUIDField(default=uuid.uuid4, primary_key=True)

    ops_id = models.CharField(max_length=30, unique=True, null=True, blank=True, verbose_name=_('ops asset id'))

    ip = models.GenericIPAddressField(max_length=32, verbose_name=_('IP'), db_index=True)

    hostname = models.CharField(max_length=128, verbose_name=_('Hostname'))

    domain = models.ForeignKey("assets.Domain", null=True, blank=True, related_name='assets', verbose_name=_("Domain"), on_delete=models.SET_NULL) # 使用Foreignkey关联外键

    created_by = models.CharField(max_length=32, null=True, blank=True, verbose_name=_('Created by'))

    date_created = models.DateTimeField(auto_now_add=True, null=True, blank=True, verbose_name=_('Date created'))

    comment = models.TextField(max_length=128, default='', blank=True, verbose_name=_('Comment'))

    def __str__(self):

        return '{0.hostname}({0.ip})'.format(self)

    class Meta:

        verbose_name = _("Asset")

domain 模型如下:apps/assets/models/domain.py

# -*- coding: utf-8 -*-

import uuid

from django.db import models

from django.utils.translation import ugettext_lazy as _

class Domain(models.Model):

    id = models.UUIDField(default=uuid.uuid4, primary_key=True)

    name = models.CharField(max_length=128, unique=True, verbose_name=_('Name'))

    comment = models.TextField(blank=True, verbose_name=_('Comment'))

    date_created = models.DateTimeField(auto_now_add=True, null=True, verbose_name=_('Date created'))

    class Meta:

        verbose_name = _("Domain")

    def __str__(self):

        return self.name

模型说明

Assets 模型中有个domain字段,使用 ForeignKey 关联 Domain模型, 并指定 related_name= assets, 表示在domain模型中,会隐藏一个

assets字段. 在使用反向查找时(通过domain查assets)使用此字段

二. 序列化: serializers

序列化类用来对request/response参数进行校验. 这里使用 ModelSerializer

代码: apps/assets/serializers/domain.py

# -*- coding: utf-8 -*-

from rest_framework import serializers

from ..models import Domain

class DomainBindAssetSerializer(serializers.ModelSerializer):

    class Meta:

        model = Domain

        fields = ['id','name','assets']

        read_only_fields = ('id', 'name')

    def update(self, instance, validated_data):

        instance.id = validated_data.get('id',instance.id)

        instance.name = validated_data.get('name',instance.name)

        instance.save()

        instance.assets.set(validated_data.get('assets',instance.assets.all()))

        return instance

代码解析
- fields = ['id','name','assets'] 说明此序列化检验字段
- update 方法为了绑定接口 更新字段, 特别注意, assets字段是隐藏字段,不能直接更新domain的assets字段, 需要使用domain.assets.set(object)
- 最后返回domain实例

三, 视图: views

视图函数使用标准的 restful接口.

实现反向更新domain下的assets

代码: apps/assets/api/domain.py

# ~*~ coding: utf-8 ~*~

from common.permissions import IsOrgAdminOrAppUser

from common.utils import get_logger

from rest_framework import status

from rest_framework.generics import RetrieveUpdateDestroyAPIView

from rest_framework.views import Response

from .. import serializers

from ..models import Domain, Gateway

class DomainWithAssetsUpdateApi(RetrieveUpdateDestroyAPIView):

    queryset = Domain.objects.all()

    serializer_class = serializers.DomainBindAssetSerializer

    permission_classes = ()

    authentication_classes = ()

    def get_object(self, pk):

        try:

            return Domain.objects.get(id=pk)

        except Domain.DoesNotExist:

            logger.error("domain id is not existed.")

            False

    def get(self, request, *args, **kwargs):

        """query domain with assets"""

        data = {"msg": '', 'result': None, 'code': None}

        domain = self.get_object(kwargs.get('pk'))

        try:

            if not domain:

                raise Exception("Domain not exists! Check url!")

            serializer = serializers.DomainBindAssetSerializer(domain)

            code = status.HTTP_200_OK

            data['result'] = serializer.data

            data['code'] = code

            logger.info("Domain bind assets:{}".format(domain.assets))

        except Exception as e:

            code = status.HTTP_422_UNPROCESSABLE_ENTITY

            data['msg'] = str(e)

            data['code'] = code

            logger.error(str(e))

        finally:

            return Response(data=data, status=code)

    def put(self, request, *args, **kwargs):

        """bind assets to domain"""

        data = {"msg": '', 'result': None, 'code': None}

        domain = self.get_object(kwargs.get("pk", None))

        if not domain:

            code = status.HTTP_404_NOT_FOUND

            data['msg'] = "Domain not exists, check url!"

            data['code'] = code

            return Response(data=data, status=code)

        try:

            serializer = serializers.DomainBindAssetSerializer(data=request.data, instance=domain, partial=True)

            if serializer.is_valid():

                serializer.save()

                code = status.HTTP_202_ACCEPTED

                data['result'] = serializer.data

                data['code'] = code

            else:

                code = status.HTTP_422_UNPROCESSABLE_ENTITY

                data['msg'] = serializer.errors

                data['code'] = code

        except Exception as e:

            code = 500

            data['msg'] = str(e)

            data['code'] = code

            logger.error("Assets bind domain occur error:{}".format(str(e)))

        finally:

            return Response(data=data, status=code)

代码说明
- 接口只实现: 查询(get), 更新(put)接口
- get接口通过url解析当前查询domain.id, 使用DomainBindAssetSerializer反序列化查询的结果并返回给接口.
- put接口相对复杂一下:
  - 首先将使用DomainBindAssetSerializer将请求的字段request.data进行序列化, partial=True表示允许只更新要修改的字段.
  - 将解析的结果进行校验
  - 如果正常,使用save(),即调用 DomainBindAssetSerializer . update()的方法对数据进行更新

四, 路由: urls

定义访问路由

代码如下:apps/assets/urls/api_urls.py

# coding:utf-8

from django.urls import path

from rest_framework_bulk.routes import BulkRouter

from rest_framework_nested import routers

from .. import api

app_name = 'assets'

router = BulkRouter()

router.register(r'assets', api.AssetViewSet, 'asset')

router.register(r'domain', api.DomainViewSet, 'domain')

urlpatterns = [

	...

    path('domain/<uuid:pk>/assets/',api.DomainWithAssetsUpdateApi.as_view(), name='domain-assets-update'),

    ...

]

urlpatterns += router.urls + cmd_filter_router.urls

五. 测试 : test

测试使用postman

get 查询接口: /api/assets/v1/domain/e5d52f79-42fc-4147-8c76-296bb7cae37b/assets/

// 返回格式如下

{

  "msg": "",

  "result": {

    "id": "e5d52f79-42fc-4147-8c76-296bb7cae37b",

    "name": "mao",

    "assets": [

      "323fff34-1baf-46b8-9784-cb2fc6046966",

      "5c65c106-1750-47de-a2f3-031c07996eda",

      "940cd754-267a-4531-88cd-e4cc248cc936"

    ]

  },

  "code": 200

}

put 更新接口: /api/assets/v1/domain/e5d52f79-42fc-4147-8c76-296bb7cae37b/assets/

// request data

{

    "assets": [

      "323fff34-1baf-46b8-9784-cb2fc6046966",

      "5c65c106-1750-47de-a2f3-031c07996eda",

    ]

}

//response data

{

  "msg": "",

  "result": {

    "id": "e5d52f79-42fc-4147-8c76-296bb7cae37b",

    "name": "mao",

    "assets": [

      "323fff34-1baf-46b8-9784-cb2fc6046966",

      "5c65c106-1750-47de-a2f3-031c07996eda"

    ]

  },

  "code": 202

}