Is response_filter behaving as expected/intended?

[filipebezerra]

I'm using Flask-Caching Version: 1.9.0

I'm trying to figure out how response_filter behaves, it looks like it doens't prevent 500 responses. For instance let's suppose we setup redis backend and the application weren't able to connection because something bad happened to connect to redis instance, so it throws an redis.exceptions.ConnectionError, in the way the decorator memoize was written the response_filter calllable will end up not having the chance to handle this connection error and the application will throw the 500 error to the client.

I'm right here folks?

[sh4nks]

No, in this case it can't prevent 500 responses - you'd have to check in your app if your caching backend works or not.

[filipebezerra]

I see, in this case is it possible to extend response_filter to support that case? I could work with that if it is possible.

I agree with you that is on the application developer the responsability to check if the Redis server is available or not, but I think it's flask-caching responsability to not throw such kind of exception, handling it and maybe throwing a specific error or even a warning log.

It will be more handy to use response_filter to avoid that application crashes when was trying to cache the response.

[sh4nks]

If you have got an idea on how to solve that, feel free to open a new PR :)
I'll try to review it as soon as possible.