django restful framework 一對多方向更新數據庫

目錄

• django restful framework 序列化
  • 一 . 數據模型: models
  • 二. 序列化: serializers
  • 三, 視圖: views
  • 四, 路由: urls
  • 五. 測試 : test

django restful framework 序列化

案例: 一個網域domain可以綁定多台服務器主機assets, 但是一台服務器只能綁定一個網域. 數據模型之間關系適用於一對多.

一 . 數據模型: models

1. 定義 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關聯外鍵
       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")
   

2. 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

3. 模型說明

• Assets 模型中有個domain字段,使用 ForeignKey 關聯 Domain模型, 並指定 related_name= assets, 表示在domain模型中,會隱藏一個

  assets字段. 在使用反向查找時(通過domain查assets)使用此字段

二. 序列化: serializers

1. 序列化類用來對request/response參數進行校驗. 這里使用 ModelSerializer

2. 代碼: 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
   

3. 代碼解析

   • fields = ['id','name','assets'] 說明此序列化檢驗字段
   • update 方法為了綁定 接口 更新字段, 特別注意, assets字段是隱藏字段,不能直接更新domain的assets字段, 需要使用domain.assets.set(object)
   • 最后返回domain實例

三, 視圖: views

視圖函數使用標准的 restful接口.

1. 實現反向更新domain下的assets

2. 代碼: 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)
   

3. 代碼說明

   • 接口只實現: 查詢(get), 更新(put)接口
   • get接口通過url解析當前查詢domain.id, 使用DomainBindAssetSerializer反序列化查詢的結果並返回給接口.
   • put接口相對復雜一下:
     • 首先將使用DomainBindAssetSerializer將 請求的字段request.data進行序列化, partial=True表示允許只更新要修改的字段.
     • 將解析的結果進行校驗
     • 如果正常,使用save(),即調用 DomainBindAssetSerializer . update()的方法對數據進行更新

四, 路由: urls

定義訪問路由

1. 代碼如下: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. 測試 : test

測試使用postman

1. get 查詢接口: /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
}

2. 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
}