General view, DRF view review

1 Preparation for creating a new project

1.1 Create a new project in the command box

Open the specified folder , Enter cmd Open the command line
django-admin startproject Project name Create project

1.2 Create sub applications in new projects

python manage.py startapp Subapplication name

1.3 Register subapplication

stay settings.py Register the sub application in the file

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
	'corsheaders',  # Configure cross domain 
    'rest_framework',   # To configure drf frame 
    ' The name of the created sub application '    # Register subapplication 
]

1.5 Configuration database

stay settings.py In the file

#  Configuration database 
DATABASES = {
    
    'default': {
    
        'ENGINE': 'django.db.backends.mysql',  #  Use mysql database 
        'HOST': 'localhost',  #  host 
        'PORT': 3306,  		#  port 
        'USER': 'root',  	#  The user name of the database 
        'PASSWORD': ' password ', #  Database password 
        'NAME': ' Database name created ',  	#  Database name 
    }
}

1.6 Modify language and time zone

stay settings.py In the file

LANGUAGE_CODE = 'zh-Hans'  # Language 

TIME_ZONE = 'Asia/Shanghai'  # The time zone 

1.7 mount this database

In a folder with the same name as the project name init.py Install

import pymysql
pymysql.install_as_MySQLdb()

1.8 Create model classes

In the sub application folder models.py establish

from django.db import models

# Create your models here.
#BaseModel Parent class 
class BaseModel(models.Model):
    created_time=models.DateTimeField(auto_now_add=True)
    update_time=models.DateTimeField(auto_now=True)

# Departmental table 
#name  Department name  varchar(30)
class Department(BaseModel):
    name=models.CharField(' Department name ',max_length=30)
    def __str__(self):
        return self.name
    class Meta:
        db_table='tb_department'

# position 
class Duty(BaseModel):
    name = models.CharField(max_length=30, verbose_name=' Job title ')

    def __str__(self):
        return self.name
    class Meta:
        db_table = 'tb_duty'
# staff 
class Staff(models.Model):
    SEX_CHOICE=(
        (1,' male '),
        (2,' Woman ')
    )
    name=models.CharField(' full name ',max_length=20)
    sex=models.IntegerField(' Gender ',choices=SEX_CHOICE,default=1)
    phone=models.CharField(' cell-phone number ',max_length=11)
    email=models.EmailField(max_length=60)
    # Foreign keys 
    department=models.ForeignKey(Department,on_delete=models.CASCADE)
    duty=models.ForeignKey(Duty,on_delete=models.CASCADE)

#user
from django.contrib.auth.models import AbstractUser
from django.utils import timezone
class User(AbstractUser):
    mobile=models.CharField(' cell-phone number ',max_length=11)
    last_login = models.DateTimeField(' Last login time ',default=timezone.now)
    def __str__(self):
        return self.username
    class Meta:
        db_table='user'

1.9 After creating the model class, migrate

Execute at the terminal within the project
Generate migration file ：python manage.py makemigrations
Perform the migration :python manage.py migrate
If the migration goes wrong , Delete the database and create a new database , The generated migration file is also deleted , Redo the above 2 A step

Fore and aft end separation

The main pursuit of the front end is beauty 、 Fluent 、 compatible
The back-end pursues three high , High performance 、 High concurrency 、 High availability

What is? restful style

Additions and deletions
GET： get data
POST： Submit data , Create data
PUT： Submit data , Update data
DELETE： Delete data
Status code
200 [GET] Status code when obtaining data
201 [POST/PUT/PATCH] Add or create data
204 [DELETE] Status code for deletion

2.DRF engineering

Download third-party modules

Install in the black window
pip install djangorestframework

stay settings.py Registration in file

Cross domain is also done by the way

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'corsheaders',# Cross domain 
    'myapp',
    'rest_framework',
]
MIDDLEWARE = [
    'django.middleware.security.SecurityMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    # 'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
    'corsheaders.middleware.CorsMiddleware'   #  Add cross domain Middleware 
]
CORS_ORIGIN_WHITELIST=[
    'http://127.0.0.1:8080',
    'http://localhost:8080'
]
CORS_ALLOW_CREDENTIALS=True
CORS_ALLOW_METHODS=('*')
CORS_ALLOW_HEADERS=('*')

Serializer automatically gets

Create a serializers.py File write class method

from rest_framework import serializers
# from rest_framework.serializers import ModelSerializer
from .models import *

#  Department serializer 
class DepartmentSer(serializers.Serializer):
    #iabel= Customize the output name after serialization 
    id=serializers.IntegerField(label='ID',read_only=True)
    #trim_whitespace=True  Remove the blanks on both sides before saving into the database 
    name=serializers.CharField(label=' Department name ',min_length=2,max_length=10,allow_null=True,
                               allow_blank=True,trim_whitespace=True)
class DepartmentSerModelser(serializers.ModelSerializer):
    class Meta:
        model=Department
        fields='__all__'
        read_only_fields=['id',]

# Job serializer 
class DutySer(serializers.Serializer):
    id = serializers.IntegerField(label='ID', read_only=True)
    name = serializers.CharField(label=' Job title ', min_length=2, max_length=10, allow_null=True,
                                 allow_blank=True, trim_whitespace=True)
class DutySerModelser(serializers.ModelSerializer):
    class Meta:
        model=Duty
        fields='__all__'
        read_only_fields=['id',]
from rest_framework.exceptions import ValidationError
# Serializer for employees 
class StaffSer(serializers.Serializer):
    id = serializers.IntegerField(label='ID', read_only=True)
    name = serializers.CharField(label=' Employee name ', min_length=2, max_length=10, allow_null=True,
                                 allow_blank=True, trim_whitespace=True)
    sex =serializers.IntegerField(label=' Gender ',default=1)
    phone=serializers.CharField(label=' cell-phone number ',min_length=11,max_length=11,allow_null=True,allow_blank=True,)
    # email=serializers.CharField(label=' mailbox ',max_length=60)
    # Foreign keys 
    department=serializers.PrimaryKeyRelatedField(queryset=Department.objects.all())
    duty=serializers.PrimaryKeyRelatedField(queryset=Duty.objects.all())
    #  Serialized method fields 
    department_name=serializers.SerializerMethodField(read_only=True)
    def get_department_name(self,obj):
        return obj.department.name
    duty_name=serializers.SerializerMethodField(read_only=True)
    def get_duty_name(self,obj):
        return obj.duty.name
    # data verification 
    def validate(self, attrs):
        # get data 
        name=attrs.get('name')
        ...
        phone=attrs.get('phone')
        # Check the data 
        if not phone.startswith('17'):
            raise ValidationError(' The mobile phone number does not comply with the rules ')
        return attrs
    # rewrite create Method 
    def create(self, validated_data):
        # ** Unpack 
        staff=Staff.objects.create(**validated_data)
        return staff
    # rewrite uodate Method 
    def update(self, instance, validated_data):
        # Add the field name if you want to modify something 
        instance.name=validated_data.get('name')
        instance.phone=validated_data.get('phone')
        instance.save()
        return instance

class StaffModelser(serializers.ModelSerializer):
    class Meta:
        model=Staff
        fields='__all__'
        read_only_fields=['id',]

The concept of view set mixed with classes

stay ModelViewSet Inherit from class GenericAPIView, It is also used in various action implementations , Through the behavior of various mixed classes , Contains .list、.retrieve、.create、.update、.partial_update、 and .destroy Other methods , Inherit ListModelMixin、RetrieveModelMixin、CreateModelMixin、UpdateModelMixin、DestroyModelMixin

drf Additions and deletions

The common method is to add, check and change

from rest_framework.views import APIView
from rest_framework.response import Response
from users.models import BaseModel,Department,Duty,Staff
from users.serializers import StaffSer
class Staffview(APIView):
    def get(self,request):
        # Check all employees 
        stf_all=Staff.objects.all()
        # serialize , Return a serializer object 
        ser=StaffSer(stf_all,many=True)
        return Response(ser.data)
    def post(self,request):
        name=request.data.get('name')
        # Query the employee object according to the user name 
        staff=Staff.objects.filter(name=name)
        if staff:
            return Response({
    'code':400,'msg':' Employee already exists '})
        # Employees can be added normally if they do not exist  # Deserialization 
        ser=StaffSer(data=request.data)
        # data verification 
        if ser.is_valid(raise_exception=True):
            #  Save the data 
            ser.save()   #create  Method 
            return Response({
    'code':200,'msg':' Add employee successfully '})
        else:
            return Response({
    'code':400,'msg':ser.errors})

# Employee details 
class Staffview2(APIView):
    #orm Query individual data 
    def get(self,request,pk):
        try:
            sta_data=Staff.objects.get(id=pk)
        except Exception as a:
            return Response({
    'msg':' Employees don't exist '})
        # Yes ORM Operate the queried data to serialize q
        ser=StaffSer(sta_data)
        return Response(ser.data)
    def put(self,request,pk):
        # Query the updated object 
        staff=Staff.objects.filter(id=pk).first()
        # Deserialization   to update  # Partial update 
        # instance The object to be modified 
        # data  Data to be modified 
        # partial=True  Modify all by default , by True when , Some fields can be modified 
        ser=StaffSer(instance=staff,data=request.data,partial=True)
        # Check the data 
        if ser.is_valid():
            ser.save()  #update
            return Response({
    'code':200,'msg':' The update is successful '})
        else:
            return Response({
    'code':400,'msg':ser.errors})
    def delete(self,request,pk):
        return Response({
    'code':200,'msg':' Delete employee succeeded '})

GenericAPIView Use Mix in extension classes

GenericAPIView Inherited from APIVIew, Added common support methods for list view and detail view , Can be paired with one or more Mixin The extension class , To achieve other more advanced functions .

from rest_framework.response import Response
from rest_framework.generics import *
from rest_framework.mixins import *
rom users.models import BaseModel,Department,Duty,Staff
from users.serializers import StaffSer,StaffModelser
# Look at employees 
class Staffview(GenericAPIView,ListModelMixin,CreateModelMixin):
    queryset = Staff.objects.all()
    serializer_class = StaffSer
    def get(self,request,*args,**kwargs):
        return self.list(request,*args,**kwargs)
    def post(self,request,*args,**kwargs):
        return self.create(request,*args,**kwargs)

# Employee details 
class Staffview2(GenericAPIView,RetrieveModelMixin,UpdateModelMixin,DestroyModelMixin):
    queryset = Staff.objects.all()
    serializer_class = StaffSer
    #orm Query individual data 
    def get(self,request,pk):
        try:
            sta_data=Staff.objects.get(id=pk)
        except Exception as a:
            return Response({
    'msg':' Employees don't exist '})
        ser=StaffSer(sta_data)
        return Response(ser.data)
    def put(self,request,pk):
        return self.update(request,pk)
    def delete(self,request,pk):
        return self.destroy(request.pk)

Subclass view

notes ： Subclass views are in from rest_framework.generics Module .

from rest_framework.generics import *
from users.models import BaseModel,Department,Duty,Staff
from users.serializers import StaffSer,StaffModelser
# View employees and add employees 
class Staffview(ListCreateAPIView):
    queryset = Staff.objects.all()
    serializer_class = StaffSer

# Employee details , Modify employees , Delete employee 
class Staffview2(RetrieveUpdateDestroyAPIView):
    queryset = Staff.objects.all()
    serializer_class = StaffSer
    lookup_field = 'pk'
    lookup_url_kwarg = 'pk'

Configure the routing

from django.urls import path
from users import views
urlpatterns = [
    # path('admin/', admin.site.urls),
    #  View all employees 
    path('staffs/',views.Staffview.as_view()),
    #  Employee details 
    path('staffs/<int:pk>/',views.Staffview2.as_view())
]

View set implementation

What is a view set
View set is simply a group of view logic operations Function collection , And... Can be used Route mapping Function selection in different ways , The built-in logical methods written are no longer named with requests , Instead, use functions to name

from rest_framework.viewsets import ModelViewSet
from users.models import BaseModel,Department,Duty,Staff
from users.serializers import StaffSer,StaffModelser
# View set 
class Staffview(ModelViewSet):
    queryset = Staff.objects.all()
    serializer_class = StaffSer

Configure the routing

from django.urls import path
from users import views
from rest_framework import routers
urlpatterns = [
]
# Generate routing object 
router=routers.SimpleRouter()
#2. Generate a route using a route object 
# Parameters 1： Name of the path  2： View set used  3： Give the generated route a name 
router.register('staffs',views.Staffview,'staffs')
#3. Route append 
urlpatterns+=router.urls