Question

我难以理解信号是如何发挥作用的,但我走过了几页,但都没有帮助我了解情况。

我有两种模式,我谨发出信号,在父母保存记录时,将挽救儿童模式。实际上,我要求儿童听取我向任何父母提出的申请,因为这一儿童,特别是一般的外国钥匙。

核心/模型。

from django.db import models
from django.contrib.auth.models import User
from django.contrib.contenttypes.models import ContentType
from django.contrib.contenttypes import generic

class Audit(models.Model):
    ## TODO: Document
    # Polymorphic model using generic relation through DJANGO content type
    operation  = models.CharField(max_length=40)
    operation_at = models.DateTimeField("Operation At", auto_now_add=True)
    operation_by = models.ForeignKey(User, db_column="operation_by", related_name="%(app_label)s_%(class)s_y+")
    content_type = models.ForeignKey(ContentType)
    object_id = models.PositiveIntegerField()
    content_object = generic.GenericForeignKey( content_type ,  object_id )

工作流程/模型

from django.db import models
from django.contrib.auth.models import User
from django.contrib.contenttypes.models import ContentType
from django.contrib.contenttypes import generic
from core.models import Audit


class Instances(models.Model):
    ##  TODO: Document
    ##  TODO: Replace id with XXXX-XXXX-XXXX-XXXX
    # Re
    INSTANCE_STATUS = (
        ( I ,  In Progress  ),
        ( C ,  Cancelled    ),
        ( D ,  Deleted      ),
        ( P ,  Pending      ),
        ( O ,  Completed    )
    )

    id=models.CharField(max_length=200, primary_key=True)
    status=models.CharField(max_length=1, choices=INSTANCE_STATUS, db_index=True)
    audit_obj=generic.GenericRelation(Audit, editable=False, null=True, blank=True)


    def save(self, *args, **kwargs):
        # on new records generate a new uuid
        if self.id is None or self.id.__len__() is 0:
            import uuid
            self.id=uuid.uuid4().__str__()
        super(Instances, self).save(*args, **kwargs)



class Setup(models.Model):
    ## TODO: Document
    # Polymorphic model using generic relation through DJANGO content type
    content_type=models.ForeignKey(ContentType)
    object_id=models.PositiveIntegerField()
    content_object=generic.GenericForeignKey( content_type ,  object_id )


class Actions(models.Model):
    ACTION_TYPE_CHOICES = (
        ( P ,  Python Script ),
        ( C ,  Class name ),
    )
    name=models.CharField(max_length=100)
    action_type=models.CharField(max_length=1, choices=ACTION_TYPE_CHOICES)


class Tasks(models.Model):
    name=models.CharField(max_length=100)
    Instance=models.ForeignKey(Instances)

试图创建审计模式的听众,使我能够将其与事例模式联系起来,如果新记录在实例中插入,也会自动在审计中插入一个记录。然后,我计划把这名听众与我的记忆中的若干模式联系起来。

任何想法,我如何能够做这样的事情?

Answer 1

下面的法典可以将非物物与以下的_-in-手法联系起来。在这种方法中,你建立了与审计的关系。还请见generic relations doc 。

我通常在模型中添加信号。 py where the ender has been defined. 不清楚是否需要这样做。

from django.db.models.signals import post_save

#####SIGNALS######
def after_save_instance_handler(sender, **kwargs):
    #get the saved instance
    instance_object = kwargs[ instance ]

    #get the needed data
    the_date = ...
    the_user = ...
    the_object_id = ...

    #create the relation to the audit object
    instance_object.audit_obj.create(operation="op963",operation_at=the_date,operation_by=the_user,object_id=the_object_id)

#connect the handler with the post save signal - django 1.1 + 1.2
post_save.connect(after_save_instance_handler, sender=Instances)

django 1.2 sign

in django development version they added a decorator to connect the signal. thus instead of the call above you have to add this decorator to the handler

@receiver(post_save, sender=Instances)
def after_save_instance_handler(sender, **kwargs):

django dev signals

友情链接