从django连接到多个mongodb实例

Question

我正在使用mongoengine和Django，并且在我的项目中需要在提供单个请求时连接到两个MongoDB实例。

connect("mdb1") 
#do stuff with mdb1 
... 
connect("mdb2") 
#do stuff with mdb2 

但我想知道，如果这就是做这件事的正确方法：如果我用它工作得很好。

Answer 1

Multiple database支撑在MongoEngine加入0.6

演示使用register_connection。

alias_lists = ['users-books-db', 'user-db', 'book-db'] # list of aliases 
dbs = ['author-book-pairs', 'users', 'books'] # list of databases 
for alias, db in zip(alias_lists, dbs): 
    register_connection(alias, db) 

class User(Document): 
    name = StringField() 
    meta = {"db_alias": "user-db"} 

class Book(Document): 
    name = StringField() 
    meta = {"db_alias": "book-db"} 

class AuthorBooks(Document): 
    author = ReferenceField(User) 
    book = ReferenceField(Book) 
    meta = {"db_alias": "users-books-db"} 

Answer 2

我认为那里s no a proper way to do this. The example of Matt turns obrigatory use an connection by Document type. If i want to use one document with many connections the example don吨适合。

Answer 3

@Ricardo官方文档里有一节解释上下文管理（即使用相同文档切换数据库：http://mongoengine-odm.readthedocs.org/en/latest/guide/connecting.html#context-managers）。 下面的代码将在类User，原本储存在users-db切换到新的数据库archive-user-db

from mongoengine.context_managers import switch_db 

class User(Document): 
    name = StringField() 

    meta = {"db_alias": "user-db"} 

with switch_db(User, 'archive-user-db') as User: 
    User(name="Ross").save() # Saves the 'archive-user-db'