是否可以从应用程序创建和连接 Django 数据库？

Question

一个例子。

在用户注册时的系统中，django create a new database 会生成具有确切设置的迁移和创建新数据库。

Answer 1

DATABASE_ROUTERS = ['base.routers.routers.TenantRouter']


MIDDLEWARE = [
    ...
    'base.middleware.middleware.Multidb',
    ...
]

def Multidb(get_response):

def middleware(request):

    try:
        usuario = request.user
        empresa = usuario.empresa
    except:
        empresa = request.GET['empresa']


    @thread_local(using_db=empresa)
    def execute_request(request):
        return get_response(request)

    response = execute_request(request)

    return response

return middleware

class TenantRouter(object):

    def db_for_read(self, model, **hints):
        return get_thread_local('using_db', 'default')

    def db_for_write(self, model, **hints):
        return get_thread_local('using_db', 'default')

    def allow_relation(self, obj1, obj2, **hints):
        return True

    def allow_migrate(self, db, app_label, model_name=None, **hints):
        return True

class thread_local(object):
    """ a decorator that wraps a function in a thread local definition block
    useful for passing variables down the stack w/o actually passing them
    examples: what database to read from, whether to cache queries, etc
    adapted from django.test.utils.override_settings
    Usage:
    @thread_local(SITE_NAME_SHORT='foobar')
    def override(request):
        ...
    """

    def __init__(self, **kwargs):
        self.options = kwargs

    def __enter__(self):
        for attr, value in self.options.items():
            setattr(threadlocal, attr, value)

    def __exit__(self, exc_type, exc_value, traceback):
        for attr in self.options.keys():
            setattr(threadlocal, attr, None)

    def __call__(self, test_func):

        @wraps(test_func)
        def inner(*args, **kwargs):
            # the thread_local class is also a context manager
            # which means it will call __enter__ and __exit__
            with self:
                return test_func(*args, **kwargs)

        return inner


def get_thread_local(attr, default=None):
    """ use this method from lower in the stack to get the value """
    return getattr(threadlocal, attr, default)

是否可以从应用程序创建和连接 Django 数据库？

Is it possible to create and connect Django databases from the application?

python

django

django-database

python-3.x