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Swagger codegen for Flask (Python). Access to shared Python object from models and controllers

New Contributor

Swagger codegen for Flask (Python). Access to shared Python object from models and controllers

Hello, I have an existing (and fully functioning) REST API built with Flask that I am re-implementing using the OpenAPI 3.0 for the heck of it.

I am using the Swagger codegen to jumpstart the server part. First a general question: is there a document/tutorial/blogpost that explains how the different bits hang together?

Looking at the files in the swagger_server folder it sort of makes sense, but I could still use an overview of some kind (apologies if it's somewhere in plain sight, I couldn't find it).


Here is my specific question. In my existing server, I have a pretty heavy initialization part that generates some large "in-memory" data structures. As my current implementation is a monolithic file, that's not an issue. But as controllers and models will need to access this data structure (and re-initializing it each time is out of question), how do you recommend that I access this shared object from within controllers and model? Is there a way for me to set a reference in that I can access from all the other classes? Or should I create some kind of singleton?  Or am I missing something?


Hopefully what I wrote made sense. 


Thank you

New Member



I realize this is an old question but as for a singleton one can create a module such as `` and import and use it wherever you need it. The rest I am busy figuring out myself still.




New Contributor

So, here is my solution, in case it's useful to others. I added the heavy duty part to the file and then made it accessible to models and controllers through the app context:


heavy = ... real heavy, gets computed once a t startup

def main():
        current_app.heavy = heavy


Controller methods can access the heavy stuff with:


    with current_app.app_context():
        heavy = current_app.heavy


If there is a better way to do it, please let me know. This cuts it for me. 

PS: thank you Hans for your suggestion. Didn't work for me.

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