django 信號(hào)調(diào)度機(jī)制詳解

Model signals
  pre_init          # django的modal執(zhí)行其構(gòu)造方法前，自動(dòng)觸發(fā)
  post_init          # django的modal執(zhí)行其構(gòu)造方法后，自動(dòng)觸發(fā)
  pre_save          # django的modal對(duì)象保存前，自動(dòng)觸發(fā)
  post_save          # django的modal對(duì)象保存后，自動(dòng)觸發(fā)
  pre_delete         # django的modal對(duì)象刪除前，自動(dòng)觸發(fā)
  post_delete         # django的modal對(duì)象刪除后，自動(dòng)觸發(fā)
  m2m_changed         # django的modal中使用m2m字段操作第三張表（add,remove,clear）前后，自動(dòng)觸發(fā)
  class_prepared       # 程序啟動(dòng)時(shí)，檢測(cè)已注冊(cè)的app中modal類(lèi)，對(duì)于每一個(gè)類(lèi)，自動(dòng)觸發(fā)
Management signals
  pre_migrate         # 執(zhí)行migrate命令前，自動(dòng)觸發(fā)
  post_migrate        # 執(zhí)行migrate命令后，自動(dòng)觸發(fā)
Request/response signals
  request_started       # 請(qǐng)求到來(lái)前，自動(dòng)觸發(fā)
  request_finished      # 請(qǐng)求結(jié)束后，自動(dòng)觸發(fā)
  got_request_exception    # 請(qǐng)求異常后，自動(dòng)觸發(fā)
Test signals
  setting_changed       # 使用test測(cè)試修改配置文件時(shí)，自動(dòng)觸發(fā)
  template_rendered      # 使用test測(cè)試渲染模板時(shí)，自動(dòng)觸發(fā)
Database Wrappers
  connection_created     # 創(chuàng)建數(shù)據(jù)庫(kù)連接時(shí)，自動(dòng)觸發(fā)

from django.core.signals import request_finished
  from django.core.signals import request_started
  from django.core.signals import got_request_exception

  from django.db.models.signals import class_prepared
  from django.db.models.signals import pre_init, post_init
  from django.db.models.signals import pre_save, post_save
  from django.db.models.signals import pre_delete, post_delete
  from django.db.models.signals import m2m_changed
  from django.db.models.signals import pre_migrate, post_migrate

  from django.test.signals import setting_changed
  from django.test.signals import template_rendered

  from django.db.backends.signals import connection_created


  def callback(sender, **kwargs):
    print("xxoo_callback")
    print(sender,kwargs)

  xxoo.connect(callback)
  # xxoo指上述導(dǎo)入的內(nèi)容

from django.core.signals import request_finished
from django.dispatch import receiver

@receiver(request_finished)
def my_callback(sender, **kwargs):
  print("Request finished!")

import django.dispatch
pizza_done = django.dispatch.Signal(providing_args=["toppings", "size"])

def callback(sender, **kwargs):
  print("callback")
  print(sender,kwargs)
 
pizza_done.connect(callback)

from 路徑 import pizza_done
 
pizza_done.send(sender='seven',toppings=123, size=456)

from django.db.models import signals

def before_save1(*args,**kwargs):
  print('有車(chē)來(lái)了，我要服務(wù)了--》',args,kwargs)

def before_save2(*args,**kwargs):
  print('有車(chē)來(lái)了，我要服務(wù)了--》',args,kwargs)

def after_save1(*args,**kwargs):
  print('有車(chē)來(lái)了，完事了--》',args,kwargs)

# 增加之前
signals.pre_save.connect(before_save1)
signals.pre_save.connect(before_save2)
# 增加之后
signals.post_save.connect(after_save1)

django_signals/__init__.py