Getting CORS to work with Flask

If you've ever created a web application you might have run into difficulties with Cross Origin Resource Sharing which is commonly referred to by its acronym CORS.

Recently I've been looking at some web projects and I ran into a particularly annoying issue with getting CORS to work with Flask. This particular project was using Flask-CORS to do the necessary CORS handling.

It turns out that if you use blueprints with Flask then CORS is not automatically applied to these blueprints. You have to manually enable CORS on each and every blueprint. There's an open issue about this from 2019 but as far as I can tell this is still the case in 2021.

Published: Tue 14 September 2021

By Janis Lesinskis

In Software-engineering

Tags: flask web-development CORS software-engineering

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Janis Lesinskis' Blog

Getting CORS to work with Flask

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