data class autoregister

tonny

hi
I dont understand how DataCls is autoregistered in backtrader.stores.IBStore.
The code in backtrader.stores.ibstore:

class IBStore(with_metaclass(metasingleton,object)):
    #######
    DataCls = None # DataCls will autoregister?
    @classmethed
    def getdata(##):
        return cls.DataCls(###)

When I create a Singleton of class IBStore by

store = backtrader.stores.IBStore(####)

and then I can get a ibdata instance by calling the store's method as your doc explained:

data = store.getdata(####)

so how it is done?

backtrader

Because the data feed IBData registers itself in the store overwriting DataCls. This would allow anyone to write a different version of IBData (call it MyIBData), which would again overwrite the value of DataCls in the store.

And consequently, getdata would return an instance of MyIBData