首页 > 解决方案 > 在 django 信号中,如何将发送者的类变量(模型字段)传递给接收者(management.call_command 函数)并使用它

问题描述

我正在使用第三方包(django-tenants)构建一个多租户项目,这使我可以从它自己的类中派生租户和域模型:

from django_tenants.models import TenantMixin, DomainMixin

class Tenant(TenantMixin):
    name = models.CharField(max_length=100)
    email = models.CharField(max_length=100)
    created_on = models.DateField(auto_now_add=True)
    auto_create_schema = True
    auto_drop_shema = True

class Domain(DomainMixin):
    pass;

长话短说,我想创建一个 API 视图来注册租户,但我无法理解包代码并且在尝试创建 TenantManager 时失败;但我确实弄清楚了如何使用 django.core.management.call_commands 从代码内部调用 django-tenants (python manage.py create_tenant/create_tenant_superuser) 提供的 CLI 管理命令:

management.call_command(
    'create_tenant', 
    domain_domain = 'tenant1.mysite.com', 
    schema_name = 'tenant1Schema',
    name ='tenant1Name',
    email = 't1@t1.com', 
    domain_is_primary = True,
    )

所以我想出了临时简化的解决方案——另一个模型(Founder)是用常规的models.Model和它自己的genericAPIview制作的,我知道如何创建。发布此模型后,我想将信号执行到我的自定义 management.call_command。

据我了解,django 信号分为三个部分:

基于这种理解,我得到:

class Founder(models.Model):
    first_name = models.CharField(max_length=200)
    last_name = models.CharField(max_length=200)
    email = models.CharField(max_length=200, unique=True)
    tenant_name = models.CharField(max_length=200)
    domain_name = models.CharField(max_length=200)

    def generate(self):
        data = (Founder.first_name, Founder.last_name, Founder.email, Founder.tenant_name, Founder.domain_name)
        save_founder(sender=self, data=data)

save_founder = Signal(providing_args=['first_name','last_name','email','tenant_name','domain_name'])

@receiver(save_founder) def generate_tenant(sender, first_name, last_name, email, tenant_name, domain_name , **kwargs):
    management.call_command(
        'create_tenant', 
        domain_domain = sender.domain_name, 
        schema_name = sender.tenant_name,
        name = sender.tenant_name,
        email = sender.email, 
        domain_is_primary = True,
        ) save_founder.connect(generate_tenant)

但在我的控制台中,我得到:

python manage.py shell
from tenant.models import Founder
f = Founder()
f.generate()
Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "/app/tenant/models.py", line 26, in generate
TypeError: 'Signal' object is not callable

标签: djangodjango-signalsdjango-management-command

解决方案


所需要的是将实例传递给接收器函数。信号不应该是定制的。我不知道我是否必须让我的接收器函数成为 Founder 类的方法,但这并没有什么坏处。这是有效的:

class Founder(models.Model):
    tenant_name = models.CharField(max_length=200)
    domain_name = models.CharField(max_length=200)
    ...
    def generate(sender, instance, **kwargs):
        founder=instance
        management.call_command(
            'create_tenant', 
            domain_domain = instance.domain_name + ".mysite.com", 
            name = instance.tenant_name,
            ...
            )
post_save.connect(Founder.generate, sender=Founder) 

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