组件化10大接口
表设计
基表
Model类的内部配置Meta类要设置abstract=True,这样的Model类就是用来作为基表
多表:Book,Publish,Author,AuthorDetail
- 基表必须设置abstract,基表就是给普通Model类继承使用的,
- 设置了abstract就不会完成数据库迁移完成建表
- abstract 目的就是只为了继承设置,并且告诉django,不要进行建立这个表格
表断关联
db_constraint=False
1、表之间没有外键关联,但是有外键逻辑关联(有充当外键的字段)
2、断关联后不会影响数据库查询效率,但是会极大提高数据库增删改效率(不影响增删改查操作)
3、断关联一定要通过逻辑保证表之间数据的安全
4、断关联 db_constraint=False,将表之间的关系断掉,可以在逻辑上依旧可以连表
5、级联关系
作者没了,详情也没:on_delete=models.CASCADE,删除作者,详情也会一并删除,级联删除
出版社没了,书还是那个出版社出版:on_delete=models.DO_NOTHING,删除出版社,书的出版社不变,不删除级联
部门没了,员工没有部门(空不能):null=True, on_delete=models.SET_NULL,删除个人的部门,设置外键字段为空
部门没了,员工进入默认部门(默认值):default=0, on_delete=models.SET_DEFAULT。删除个人的部门,设置所有的外键字段为0
ORM外键设计
1、一对多:外键放在多的一方
2、多对多:外键放在常用的一方
3、一对一:外键放在不常用的一方
4、外键字段为正向查询字段,related_name是反向查询字段
author = models.OneToOneField(to='Author', related_name='detail', db_constraint=False, on_delete=models.CASCADE)
有作者可以没有详情,删除作者,详情一定会被级联删除
外键字段为正向查询字段,related_name是反向查询字段
related_name='books',反向查询可以直接点books,反向查询的字段
db_constraint=False,去掉外键建立的关联
on_delete=models.DO_NOTHING,不执行级联删除
# ManyToManyField字段不提供设置on_delete,如果想设置关系表级联,只能手动定义关系表
authors = models.ManyToManyField(to='Author', related_name='books', db_constraint=False)
from django.db import models
from django.conf import settings
# 一、基表
# Model类的内部配置Meta类要设置abstract=True,这样的Model类就是用来作为基表
# 多表:Book,Publish,Author,AuthorDetail
class BaseModel(models.Model):
is_delete = models.BooleanField(default=False)
create_time = models.DateTimeField(auto_now_add=True)
class Meta:
# 基表必须设置abstract,基表就是给普通Model类继承使用的,
# 设置了abstract就不会完成数据库迁移完成建表
# abstract 目的就是只为了继承设置,并且告诉django,不要进行建立这个表格
abstract = True # 抽象的表
class Book(BaseModel):# 继承表
name = models.CharField(max_length=16)
price = models.DecimalField(max_digits=5, decimal_places=2)
# related_name='books',反向查询可以直接点books,反向查询的字段
# db_constraint=False,去掉外键建立的关联
# on_delete=models.DO_NOTHING,不执行级联删除
publish = models.ForeignKey(to='Publish', related_name='books', db_constraint=False, on_delete=models.DO_NOTHING)
# 重点:多对多外键实际在关系表中,ORM默认关系表中两个外键都是级联
# db_constraint=False
# ManyToManyField字段不提供设置on_delete,如果想设置关系表级联,只能手动定义关系表
authors = models.ManyToManyField(to='Author', related_name='books', db_constraint=False)
# 自定义连表深度,不需要反序列化,因为自定义插拔属性不参与反序列化
@property
def publish_name(self):
return self.publish.name
@property
def author_list(self):
temp_author_list = []
for author in self.authors.all():
temp_author_list.append({
'name': author.name,
'sex': author.get_sex_display(),
'mobile': author.detail.mobile
})
return temp_author_list
class Publish(BaseModel):
name = models.CharField(max_length=16)
address = models.CharField(max_length=64)
class Author(BaseModel):
name = models.CharField(max_length=16)
sex = models.IntegerField(choices=[(0, '男'), (1, '女')], default=0)
class AuthorDetail(BaseModel):
mobile = models.CharField(max_length=11)
# 有作者可以没有详情,删除作者,详情一定会被级联删除
# 外键字段为正向查询字段,related_name是反向查询字段
author = models.OneToOneField(to='Author', related_name='detail', db_constraint=False, on_delete=models.CASCADE)
返回信息格式化
from rest_framework.response import Response
class APIResponse(Response):
# 格式化data
def __init__(self, status=0, msg='ok', results=None, http_status=None, headers=None, exception=False, **kwargs):
data = { # json的response基础有数据状态码和数据状态信息
'status': status,
'msg': msg
}
if results is not None: # 后台有数据,响应数据
data['results'] = results
data.update(**kwargs) # 后台的一切自定义响应数据直接放到响应数据data中
super().__init__(data=data, status=http_status, headers=headers, exception=exception)
序列化
# 了解
fields = '__all__'#返回所有
exclude = ('id', )#除了id 其他的返回
depth = 1#连表深度查询返回
#下面俩个不能一起使用
fields = '__all__'#返回所有
exclude = ('id', )#除了id 其他的返回
from rest_framework import serializers
from . import models
class BookListSerializer(serializers.ListSerializer):
# 1、create方法父级ListSerializer已经提供了
# def create(self, validated_data):
# # 通过self.child来访问绑定的ModelSerializer
# print(self.child)
# raise Exception('我不提供')
# 2、父级ListSerializer没有通过update方法的实现体,需要自己重写
def update(self, instance, validated_data):
# print(instance)
# print(validated_data)
return [
self.child.update(instance[i], attrs) for i, attrs in enumerate(validated_data)
]
class BookModelSerializer(serializers.ModelSerializer):
# 通过BookModelSerializer.Meta.list_serializer_class来访问绑定的ListSerializer
class Meta:
# 关联ListSerializer完成群增群改
list_serializer_class = BookListSerializer
model = models.Book
# fields = ('name', 'price', 'publish', 'authors')
# fields = ('name', 'price', 'publish_name', 'author_list')
# 了解
# fields = '__all__'
# exclude = ('id', )
# depth = 1
# 序列化与反序列化整合
fields = ('name', 'price', 'publish_name',
'author_list', 'publish', 'authors')
extra_kwargs = {
'publish': {
'write_only': True
},
'authors': {
'write_only': True
}
}
十大接口
from django.conf.urls import url
from . import views
urlpatterns = [
url(r'^books/$', views.BookAPIView.as_view()),
url(r'^books/(?P<pk>\d+)/$', views.BookAPIView.as_view()),
]
from rest_framework.views import APIView
from rest_framework.response import Response
from . import models, serializers
from .response import APIResponse
class BookAPIView(APIView):
单查、群查
# 单查、群查
def get(self, request, *args, **kwargs):
pk = kwargs.get('pk')
if pk:
book_obj = models.Book.objects.filter(pk=pk, is_delete=False).first()
if not book_obj:
return APIResponse(1, 'pk error', http_status=400)
book_data = serializers.BookModelSerializer(book_obj).data
return APIResponse(results=book_data)
book_query = models.Book.objects.filter(is_delete=False).all()
return APIResponse(0, 'ok', data=serializers.BookModelSerializer(book_query, many=True).data)
单删、群删
# 单删、群删
def delete(self, request, *args, **kwargs):
"""
单删:前台数据为pk,接口为 /books/(pk)/
群删:前台数据为pks,接口为 /books/
"""
pk = kwargs.get('pk')
# 将单删群删逻辑整合
if pk: # /books/(pk)/的接口就不考虑群删,就固定为单删
pks = [pk]
else:
pks = request.data.get('pks')
# 前台数据有误(主要是群删没有提供pks)
if not pks:
return APIResponse(1, 'delete error', http_status=400)
# 只要有操作受影响行,就是删除成功,反之失败
rows = models.Book.objects.filter(is_delete=False, pk__in=pks).update(is_delete=True)
if rows:
return APIResponse(0, 'delete ok')
return APIResponse(1, 'delete failed')
单增、群增
# 单增、群增
def post(self, request, *args, **kwargs):
"""
单增:前台提交字典,接口 /books/
群增:前台提交列表套字典,接口 /books/
"""
request_data = request.data
if isinstance(request_data, dict): # 单增
book_ser = serializers.BookModelSerializer(data=request_data)
if book_ser.is_valid():
book_obj = book_ser.save()
return APIResponse(results=serializers.BookModelSerializer(book_obj).data)
return APIResponse(1, msg=book_ser.errors)
elif isinstance(request_data, list) and len(request_data) != 0 : # 群增
book_ser = serializers.BookModelSerializer(data=request_data, many=True)
book_ser.is_valid(raise_exception=True)
book_obj_list = book_ser.save()
return APIResponse(results=serializers.BookModelSerializer(book_obj_list, many=True).data)
else:
return APIResponse(1, 'data error', http_status=400)
单整体改、群整体改
class BookListSerializer(serializers.ListSerializer):
# 1、create方法父级ListSerializer已经提供了
# def create(self, validated_data):
# # 通过self.child来访问绑定的ModelSerializer
# print(self.child)
# raise Exception('我不提供')
# 2、父级ListSerializer没有通过update方法的实现体,需要自己重写
def update(self, instance, validated_data):
# print(instance)
# print(validated_data)
return [
self.child.update(instance[i], attrs) for i, attrs in enumerate(validated_data)
]
class BookModelSerializer(serializers.ModelSerializer):
# 通过BookModelSerializer.Meta.list_serializer_class来访问绑定的ListSerializer
class Meta:
# 关联ListSerializer完成群增群改
list_serializer_class = BookListSerializer
# 单整体改、群整体改
def put(self, request, *args, **kwargs):
"""
单整体改:前台提交字典,接口 /books/(pk)/
群整体改:前台提交列表套字典,接口 /books/,注每一个字典都可以通过pk
"""
pk = kwargs.get('pk')
request_data = request.data
if pk: # 单改
try:
book_obj = models.Book.objects.get(pk=pk)
except:
return APIResponse(1, 'pk error')
# 修改和新增,都需要通过数据,数据依旧给data,修改与新增不同点,instance要被赋值为被修改对象
book_ser = serializers.BookModelSerializer(instance=book_obj, data=request_data)
book_ser.is_valid(raise_exception=True)
book_obj = book_ser.save()
return APIResponse(results=serializers.BookModelSerializer(book_obj).data)
else: # 群改
if not isinstance(request_data, list) or len(request_data) == 0:
return APIResponse(1, 'data error', http_status=400)
# [{pk:1,...}, {pk:3,...}, {pk:100,...}] => [obj1, obj3, obj100] + [{...}, {...}, {...}]
# 要考虑pk对应的对象是否被删,以及pk没有对应的对象
# 假设pk3被删,pk100没有 => [obj1] + [{...}]
# 注:一定不要在循环体中对循环对象进行增删(影响对象长度)的操作
obj_list = []
data_list = []
for dic in request_data:
# request_data可能是list,单内部不一定是dict
try:
pk = dic.pop('pk')
try:
obj = models.Book.objects.get(pk=pk, is_delete=False)
obj_list.append(obj)
data_list.append(dic)
except:
pass
except:
return APIResponse(1, 'data error', http_status=400)
book_ser = serializers.BookModelSerializer(instance=obj_list, data=data_list, many=True)
book_ser.is_valid(raise_exception=True)
book_obj_list = book_ser.save()
return APIResponse(results=serializers.BookModelSerializer(book_obj_list, many=True).data)
单局部改、群局部改
# 单局部改、群局部改
def patch(self, request, *args, **kwargs):
"""
单整体改:前台提交字典,接口 /books/(pk)/
群整体改:前台提交列表套字典,接口 /books/,注每一个字典都可以通过pk
"""
pk = kwargs.get('pk')
request_data = request.data
if pk:
try:
book_obj = models.Book.objects.get(pk=pk)
except:
return APIResponse(1, 'pk error')
# 局部修改就是在整体修改基础上设置partial=True,将所有参与反序列化字段设置为required=False
book_ser = serializers.BookModelSerializer(instance=book_obj, data=request_data, partial=True)
book_ser.is_valid(raise_exception=True)
book_obj = book_ser.save()
return APIResponse(results=serializers.BookModelSerializer(book_obj).data)
else: # 群改
if not isinstance(request_data, list) or len(request_data) == 0:
return APIResponse(1, 'data error', http_status=400)
# [{pk:1,...}, {pk:3,...}, {pk:100,...}] => [obj1, obj3, obj100] + [{...}, {...}, {...}]
# 要考虑pk对应的对象是否被删,以及pk没有对应的对象
# 假设pk3被删,pk100没有 => [obj1] + [{...}]
# 注:一定不要在循环体中对循环对象进行增删(影响对象长度)的操作
obj_list = []
data_list = []
for dic in request_data:
# request_data可能是list,单内部不一定是dict
try:
pk = dic.pop('pk')
try:
obj = models.Book.objects.get(pk=pk, is_delete=False)
obj_list.append(obj)
data_list.append(dic)
except:
pass
except:
return APIResponse(1, 'data error', http_status=400)
book_ser = serializers.BookModelSerializer(instance=obj_list, data=data_list, many=True, partial=True)
book_ser.is_valid(raise_exception=True)
book_obj_list = book_ser.save()
return APIResponse(results=serializers.BookModelSerializer(book_obj_list, many=True).data)