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I wanted to start building some scenario based testing and noticed that there are some overlap of code where some scenarios re-implement code that is also present in the API.
For example, some of the scenarios (test_server_basic_ops.py for example) re-implement methods that were written in the corresponding REST client in the API.
I was wondering if there is some guidelines of what is a resalable overlap of code (though I'm not sure it really is an overlap when scenario uses the python clients and the API the REST client), for example, say I want to write a scenario for nova that tests something with the quota, I can see from the code of the API (tempest/tempest/api/compute/admin/test_quotas.py) that it has a lot of the quota related code already implemented with the REST client, so when I'm building a scenario, how much "freedom" do I have to write methods that uses the python clients instead of the API methods?


Thanks,
Tal