django之signal信号（day-32）

就像此时此刻的心情，不言而喻。。。

在app目录下创建信号文件signal_processor

from .dingtalk import send
from .models import Candidate
from .tasks import send_message
from django.contrib import messages
from django.dispatch import receiver
# @receiver(signal=pre_delete, sender=Candidate, dispatch_uid="pre_delete_notify_callback")
# @receiver(signal=post_delete, sender=Candidate, dispatch_uid="post_delete_notify_callback")
def notify_callback(sender, instance=None, created=False, **kwargs):
    candidates = ''
    interviewers = ''
    phone = []
    candidates = instance.username + ';' + candidates
    interviewers = instance.first_interviewer_user.username + ';' + interviewers
    phone.append(int(instance.first_interviewer_user.account_phone))
    send(' %s 是个大笨蛋，红颜与否，英才也罢，命皆为定数，都怪 %s ，都怪他！' % (candidates, interviewers), phone)
    logger.info(candidates)
post_delete.connect(notify_callback, sender=Candidate, dispatch_uid="post_delete_notify_callback")
# from ..jobs.models import Resume
#
#
# def notify_callback(sender, instance=None, using=None, **kwargs):
#     dict_obj = model_to_dict(instance, exclude=("picture", "attachment"))
#     message = "Instance of %s has been deleted: %s" %(type(instance), json.dumps(dict_obj, ensure_ascii=False))
#     send(message)
#
#
# post_delete.connect(notify_callback, sender=Resume, dispatch_uid="post_delete_notify_callback")

这边记录了两种方式，装饰器方式为注释的那个。
常见的signal方式见文档
eg。
Django内置了一整套信号，下面是一些比较常用的：

• django.db.models.signals.pre_save & django.db.models.signals.post_save

post_save在ORM模型的save()方法调用之前或之后发送信号

• django.db.models.signals.pre_delete & django.db.models.signals.post_delete

post_delete在ORM模型或查询集的delete()方法调用之前或之后发送信号。

• django.db.models.signals.m2m_changed

m2m_changed当多对多字段被修改时发送信号。

• django.core.signals.request_started & django.core.signals.request_finished

request_finished当接收和关闭HTTP请求时发送信号。

而后记得在apps.py文件中覆盖ready方法，否则不会生效

from django.apps import AppConfig
class InterviewConfig(AppConfig):
    default_auto_field = 'django.db.models.BigAutoField'
    name = 'interview'
    def ready(self):
        from .signal_processor import notify_callback

扩展内容：定义一个自定义信号！