package conflicts

[Rex Feng]

While deploying this demo app, I got various errors:

The conflict is caused by:
The user requested Werkzeug==2.2.3
flask 2.3.2 depends on Werkzeug>=2.3.3

and

AttributeError: module 'flask.json' has no attribute 'JSONEncoder'

My workaround was to use older packages in requirements.txt:

Flask==2.2.5
Werkzeug==2.2.3

After using this older Flask, I was able to deploy to aptible

[Bruno Fernandes]

I had the same issue. I upgraded Werkzeug instead.

[Bruno Fernandes]

Your workaround is better. It turns out Werkzeug 2.3.3 is incompatible with Flask 2.3.2.