前言
Django 的 admin 是一个 Django 自带的后台管理工具=,以往都是多个应用使用一个数据库,现在需要连接多个数据库,所以以前的套路就不行了。
1.配置setting.py
DATABASES = {
'default': { # 第一个一定要写default
'ENGINE': 'django.db.backends.mysql',
'NAME': "db_name",
'USER': "root",
'PASSWORD': "xxxxxxxx",
'HOST': "xxxxxxxx"
},
'name_2': { # 配置第二个数据库节点名称
'ENGINE': 'django.db.backends.mysql',
'NAME': 'db_name2', # 第二个数据库的名称
'USER': 'root',
'PASSWORD': 'xxxxxxxx',
'HOST': 'xxxxxxxx',
}
}
DATABASE_ROUTERS = ['project_name.database_router.DatabaseAppsRouter']
DATABASE_APPS_MAPPING = {
'app_name1': 'default',
'app_name2': 'name_2',
}
2. 创建数据库路由规则
在项目工程根路径下(与 settings.py 文件一级)创建 database_router.py 文件:
from django.conf import settings
DATABASE_MAPPING = settings.DATABASE_APPS_MAPPING
class DatabaseAppsRouter(object):
"""
A router to control all database operations on models for different
databases.
In case an app is not set in settings.DATABASE_APPS_MAPPING, the router
will fallback to the `default` database.
Settings example:
DATABASE_APPS_MAPPING = {'app1': 'db1', 'app2': 'db2'}
"""
def db_for_read(self, model, **hints):
""""Point all read operations to the specific database."""
if model._meta.app_label in DATABASE_MAPPING:
return DATABASE_MAPPING[model._meta.app_label]
return None
def db_for_write(self, model, **hints):
"""Point all write operations to the specific database."""
if model._meta.app_label in DATABASE_MAPPING:
return DATABASE_MAPPING[model._meta.app_label]
return None
def allow_relation(self, obj1, obj2, **hints):
"""Allow any relation between apps that use the same database."""
db_obj1 = DATABASE_MAPPING.get(obj1._meta.app_label)
db_obj2 = DATABASE_MAPPING.get(obj2._meta.app_label)
if db_obj1 and db_obj2:
if db_obj1 == db_obj2:
return True
else:
return False
return None
def allow_syncdb(self, db, model):
"""Make sure that apps only appear in the related database."""
if db in DATABASE_MAPPING.values():
return DATABASE_MAPPING.get(model._meta.app_label) == db
elif model._meta.app_label in DATABASE_MAPPING:
return False
return None
def allow_migrate(self, db, app_label, model=None, **hints):
"""
Make sure the auth app only appears in the 'auth_db'
database.
"""
if db in DATABASE_MAPPING.values():
return DATABASE_MAPPING.get(app_label) == db
elif app_label in DATABASE_MAPPING:
return False
return None
小知识
python manage.py inspectdb --database=db_name2
,这条命令可以生成 db_name2 数据库的模型,把模型导入到该app下的 models.py 然后再顺序执行
python manage.py makemigrations
和 python manage.py migrate
两条指令即可。