Signal for missing keys

[iurisilvio]

I want to add the key to my sqlalchemy database if it does not exist in any other handler. I can listen to some flask signal in this case to do that.

Is it a good idea? I can work on it, but maybe others have better ideas about how to handle it.

[catermelon]

I think it's a fine idea to add blinker signals for critical events, so I'm all for that.

I don't want to add support for adding keys automatically, because I think it's a likely uncommon use case and could be potentially dangerous if you didn't know what you were doing. I'm willing to be convinced otherwise, but that's my first response.

[iurisilvio]

I agree, I want this signal to make it an option, not a built-in thing.

I'll provide you an example soon.

[iurisilvio]

Done.

I don't know if a global event is better than a class level event.

from flask.ext.featureflags import missing_feature

@missing_feature.connect
def f(obj, feature):
    pass

If I change it to class level:

ff = FeatureFlag()

@ff.missing_feature.connect
def f(obj, feature):
    # obj is my FeatureFlag instance
    pass

[iurisilvio]

Closing it, because it is merged.

[catermelon]

thanks!