序列化
方式一 :在業務類裡序列化資料庫資料
class RolesView(APIView):
def get(self,request,*args,**kwargs):
roles = models.Role.objects.all().values('id','title')[1:3]
ret = list(roles)
r = json.dumps(ret,ensure_ascii=False)
return HttpResponse(r)
View Code
方式二:寫個序列化的類,在業務類中引用,序列化類中可以定制字段
class UserinfoSerializer(serializers.ModelSerializer):
#字段名與資料庫相同則替換,不同則添加
type = serializers.CharField(source='get_usertype_display')
gb = serializers.CharField(source='group.title')
class Meta:
model = models.UserInfo
#全部顯示
fields = '__all__'
#定制顯示
# fields = ['id','username','type','gb']
定制類
class UserInfo(models.Model):
usertype_choices = (
(1,'普通使用者'),
(2,'VIP使用者'),
(3,'SVIP使用者')
)
usertype = models.IntegerField(choices=usertype_choices,verbose_name='使用者類型')
username = models.CharField(max_length=32,unique=True,verbose_name='使用者名')
password = models.CharField(max_length=64,verbose_name='密碼')
group = models.ForeignKey('UserGroup',on_delete=models.DO_NOTHING,verbose_name='分組')
roles = models.ManyToManyField('Role',verbose_name='職業')
class Meta:
verbose_name = '使用者管理'
verbose_name_plural = verbose_name
def __str__(self):
return self.username
對應資料庫結構
class UserInfoView(APIView):
authentication_classes = []
permission_classes = []
def get(self,request,*args,**kwargs):
m = models.UserInfo.objects.all()
ser = UserinfoSerializer(instance=m,many=True)
#單表的話這裡many = false
return Response(ser.data)
業務類
方式二補充:source不适合many to many,many to many需要自定義顯示
role = serializers.SerializerMethodField() #自定義顯示
def get_role(self,row):
role_list = row.roles.all()
ret = []
for item in role_list:
ret.append({'id':item.id,'title':item.title})
return ret
many to many
方式三:depth根本連表結構往深層取值
class UserinfoSerializer(serializers.ModelSerializer):
usertype = serializers.CharField(source='get_usertype_display')
class Meta:
model = models.UserInfo
#全部顯示
fields = '__all__'
depth = 1 #0~10之間
#定制顯示
# fields = ['id','username','type','gb']
定制類
[{"id": 1, "usertype": 1, "username": "wrx", "password": "123", "group": {"id": 1, "title": "A組"}, "roles": [{"id": 2, "title": "老師"}, {"id": 3, "title": "醫生"}]},
{"id": 2, "usertype": 2, "username": "ylp", "password": "123", "group": {"id": 2, "title": "B組"}, "roles": [{"id": 3, "title": "醫生"}]}]
取值結果
方式四:生成連結,即把上述類的group生成連結
class UserinfoSerializer(serializers.ModelSerializer):
usertype = serializers.CharField(source='get_usertype_display')
group = serializers.HyperlinkedIdentityField(view_name='grp',lookup_field='group_id',lookup_url_kwarg='pk')
#name,pk值對應urls中的re-path
class Meta:
model = models.UserInfo
#全部顯示
fields = '__all__'
depth = 1 #0~10之間
#定制顯示
# fields = ['id','username','type','gb']
定制類
re_path(r'^(?P<version>[v1|v2]+)/group/(?P<pk>\d+)$',GroupView.as_view(),name='grp')
PS:這裡經曆了一個錯誤,如果配置了全局的版本控制(詳見版本控制配置),這裡要也要配置,否則會一直報錯
django.core.exceptions.ImproperlyConfigured: Could not resolve URL for hyperlinked relationship using view name "grp". You may have failed to include the related model in your API, or incorrectly configured the `lookup_field` attribute on this field.
class UserInfoView(APIView):
def get(self,request,*args,**kwargs):
m = models.UserInfo.objects.all()
ser = UserinfoSerializer(instance=m,many=True,context={'request':request})
return Response(ser.data)
Views業務類
PS:執行個體這個定制類的時候要加要加context={'request':request}
實際調用的是另一個views類的url
class GroupSerializer(serializers.ModelSerializer):
class Meta:
model = models.UserGroup
fields = '__all__'
class GroupView(APIView):
def get(self,request,*args,**kwargs):
pk = kwargs.get('pk')
obj = models.UserGroup.objects.filter(pk=pk).first()
ser = GroupSerializer(instance=obj, many=False)
t = json.dumps(ser.data, ensure_ascii=False)
return HttpResponse(t)
上面re_path對應的定制類和業務類
方式五:三張表互相關聯的反向查找
class Course(models.Model):
title = models.CharField(max_length=32,verbose_name='課程名稱')
course_img = models.ImageField(verbose_name='課程圖檔',upload_to = "static/img/")
course_choice = (
(0, '入門級'),
(1, '普通難度'),
(2, '中等難度'),
(3, '進階難度'),
)
level = models.IntegerField(verbose_name='課程難度',choices=course_choice,default=0)
class Meta:
verbose_name = '課程管理'
verbose_name_plural = verbose_name
def __str__(self):
return self.title
class CourseInfo(models.Model):
why = models.CharField(verbose_name='課程描述',max_length=255)
course = models.OneToOneField(to='Course',on_delete=models.DO_NOTHING,verbose_name='關聯課程')
recommend_course = models.ManyToManyField(to='Course',verbose_name='推薦課程',related_name='rc')
class Meta:
verbose_name = '課程詳細'
verbose_name_plural = verbose_name
def __str__(self):
return '課程詳細:'+self.course.title
class Section(models.Model):
num = models.IntegerField(verbose_name='章節')
name = models.CharField(max_length=64,verbose_name='課程章節')
course = models.ForeignKey(to='Course', on_delete=models.DO_NOTHING, verbose_name='關聯課程')
class Meta:
verbose_name = '課程章節'
verbose_name_plural = verbose_name
def __str__(self):
return '課程章節'+self.course.title
表結構
PS:第二張表與第一張表多對多并且單對單(這裡有個小知識點,同時多對多和單對單的時候有一張表要加related_name='rc'),第三張表與第一張表一對多,需求:通過序列化第二張表得到第一張表和第三張表的相關内容
class CourseinfoSerializer(serializers.ModelSerializer):
#單對單,單對多,choice可以用這種方式,多對多不能使用
title = serializers.CharField(source='course.title')
level = serializers.CharField(source='course.get_level_display')
#多對多需要自定義
recommends = serializers.SerializerMethodField()
def get_recommends(self, row):
role_list = row.recommend_course.all()
ret = []
for item in role_list:
ret.append({'id': item.id, 'title': item.title})
return ret
#3張表互相關聯的反向查找
sections = serializers.SerializerMethodField()
def get_sections(self, row):
role_list = row.course.section_set.all()
ret = []
for item in role_list:
ret.append({'num': item.num, 'name': item.name})
return ret
class Meta:
model = models.CourseInfo
# fields = '__all__'
fields = ['id','title','level','why','recommends','sections']
# depth = 2
定制類
def retrieve(self,request, *args, **kwargs):
ret = {'code': 1000, 'data': None}
pk = kwargs.get('pk')
try:
obj = models.CourseInfo.objects.filter(course_id=pk)
ser = sl.CourseinfoSerializer(instance=obj, many=True)
ret['data'] = ser.data
except Exception as e:
ret['code'] = 1001
ret['error'] = '擷取課程失敗'
return Response(ret)
業務類
PS:這實際是個類的get請求,re_path(r'^course/(?P<pk>\d+)$',views.CourseView.as_view({'get':'retrieve'})),
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序列化-資料驗證,驗證title資料不能為空且必須以wrx開頭
class UserGroupSerializer(serializers.Serializer):
title = serializers.CharField(error_messages={'required':'标題不能為空'},)
def validate_title(self,value):
if not value.startswith('wrx'):
message = '标題必須以%s開頭'%'wrx'
raise exceptions.ValidationError(message)
else:
return value
定制類
class UserGroupView(APIView):
def post(self,request,*args,**kwargs):
src = ''
res = UserGroupSerializer(data=request.data)
if res.is_valid():
print(res.validated_data)
src = str(res.validated_data['title'])
else:
print(res.errors)
src = str(res.errors)
return HttpResponse(src)
業務類
轉載于:https://www.cnblogs.com/wrxblog/p/10402580.html