Allow to define database dynamically

Peewee is awesome 👍 😃

I’m using Peewee in my Tornado-powered project and I need to define database connection dynamically, like that:

import tornado
from peewee import *

class Application(tornado.web.Application):

    def __init__(self, **kwargs):
        # Some init stuff ...

        # Setup DB and Models

        self.database = PostgresqlDatabase('mydb', user='postgres')

        import myapp.users.models as users
        self.User = self._get_model(users.User, self.database)

        # etc...

    def _get_model(self, model, db):
        model._meta.database = db
        model.create_table(True)
        return model

So, I’m using private undocumented _meta property and I’m not feeling ok about that and I’m not sure what is the best design decision for that.

Anybody have ideas?

[eukreign]

Is bind_ctx thread safe? Can I bind the same model to different databases in separate threads?

If it’s possible can you point me to how this works? From my investigation it seems that bind_ctx just monkey patches the class attributes with which database to use so if you set it in one thread you’d overwrite whatever it was set to in another thread, is my understanding correct?

[jiamo]

"I believe that the vast, vast majority of people use peewee with a single database. "

Yes. But still some situation for multi database.

Some application create db for every user. All db have same table. When different user request api. Using bind_ctx in one thread the model will change at runtime. And it don’t have solution but only use lock to bind model to one db.

If we have session concept , One thread have multi session. different session the model using different database. That will be very helpful.