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

from django.db.models.signals import post_init

from django.db.models.signals import pre_save

from django.db.models.signals import post_save

from django.db.models.signals import pre_delete

from django.db.models.signals import post_delete

from django.db.models.signals import m2m_changed

from django.db.models.signals import pre_migrate

from django.db.models.signals import post_migrate

from django.test.signals import setting_changed

from django.test.signals import template_rendered

from django.db.backends.signals import connection_created

# 1、定义执行的函数

def callback1(sender,**kwargs):

    print("before pre_migrate")

    print(sender,kwargs)

# 定义执行的函数

def callback2(sender,**kwargs):

    print("after pre_migrate")

    print(sender,kwargs)

# 在执行migrate之前会执行的函数

pre_migrate.connect(callback1)

# 在执行migrate之后执行的函数

post_migrate.connect(callback2)

E:\python\django_last>python manage.py migrate

Operations to perform:

  Apply all migrations: admin, app1, auth, contenttypes, sessions

before pre_migrate

<AdminConfig: admin> {'signal': <django.dispatch.dispatcher.Signal object at 0x01C755D0>, 'app_config': <AdminConfig: admin>, 'verbosity': 1, 'interactive': True, 'using': 'default', 'apps': <django.db.migrations

.state.StateApps object at 0x02CF1130>, 'plan': []}

before pre_migrate

<AuthConfig: auth> {'signal': <django.dispatch.dispatcher.Signal object at 0x01C755D0>, 'app_config': <AuthConfig: auth>, 'verbosity': 1, 'interactive': True, 'using': 'default', 'apps': <django.db.migrations.sta

te.StateApps object at 0x02CF1130>, 'plan': []}

before pre_migrate

<ContentTypesConfig: contenttypes> {'signal': <django.dispatch.dispatcher.Signal object at 0x01C755D0>, 'app_config': <ContentTypesConfig: contenttypes>, 'verbosity': 1, 'interactive': True, 'using': 'default', '

apps': <django.db.migrations.state.StateApps object at 0x02CF1130>, 'plan': []}

before pre_migrate

<SessionsConfig: sessions> {'signal': <django.dispatch.dispatcher.Signal object at 0x01C755D0>, 'app_config': <SessionsConfig: sessions>, 'verbosity': 1, 'interactive': True, 'using': 'default', 'apps': <django.d

b.migrations.state.StateApps object at 0x02CF1130>, 'plan': []}

before pre_migrate

<App1Config: app1> {'signal': <django.dispatch.dispatcher.Signal object at 0x01C755D0>, 'app_config': <App1Config: app1>, 'verbosity': 1, 'interactive': True, 'using': 'default', 'apps': <django.db.migrations.sta

te.StateApps object at 0x02CF1130>, 'plan': []}

Running migrations:

  No migrations to apply.

after pre_migrate

<AdminConfig: admin> {'signal': <django.dispatch.dispatcher.Signal object at 0x01C75610>, 'app_config': <AdminConfig: admin>, 'verbosity': 1, 'interactive': True, 'using': 'default', 'apps': <django.db.migrations

.state.StateApps object at 0x03183FD0>, 'plan': []}

after pre_migrate

<AuthConfig: auth> {'signal': <django.dispatch.dispatcher.Signal object at 0x01C75610>, 'app_config': <AuthConfig: auth>, 'verbosity': 1, 'interactive': True, 'using': 'default', 'apps': <django.db.migrations.sta

te.StateApps object at 0x03183FD0>, 'plan': []}

after pre_migrate

<ContentTypesConfig: contenttypes> {'signal': <django.dispatch.dispatcher.Signal object at 0x01C75610>, 'app_config': <ContentTypesConfig: contenttypes>, 'verbosity': 1, 'interactive': True, 'using': 'default', '

apps': <django.db.migrations.state.StateApps object at 0x03183FD0>, 'plan': []}

after pre_migrate

<SessionsConfig: sessions> {'signal': <django.dispatch.dispatcher.Signal object at 0x01C75610>, 'app_config': <SessionsConfig: sessions>, 'verbosity': 1, 'interactive': True, 'using': 'default', 'apps': <django.d

b.migrations.state.StateApps object at 0x03183FD0>, 'plan': []}

after pre_migrate

<App1Config: app1> {'signal': <django.dispatch.dispatcher.Signal object at 0x01C75610>, 'app_config': <App1Config: app1>, 'verbosity': 1, 'interactive': True, 'using': 'default', 'apps': <django.db.migrations.sta

te.StateApps object at 0x03183FD0>, 'plan': []}

E:\python\django_last>

# 1、导入模块

import django.dispatch

# 2、注册一个信号

test = django.dispatch.Signal(providing_args=["aa","bb"])

# 这里的aa和bb相当于形参

# 3、定义一个触发信号要执行的函数

def callback3(sender,**kwargs):

    print("自定义信号")

    print(sender,kwargs)

# 4、给信号注册一个函数

test.connect(callback3)

# 使用我们自定义的信号

def cus_signal(request):

    # 导入自定义的信号,这里需要注意，导入__init__下的信号，直接用下面的方式就可以了

    from django_last import test

    # 触发信号，这里要记得要传参数,sender的意思是 谁发送的信号

    test.send(sender="自定义信号",aa="django",bb="python")

    return HttpResponse("自定义信号")