This is a bit complicated for Multitenant use cases or FI cases where they want to be able to easily do a core conversion.
I recommend you look through https://docs.q2developer.com/docs/guides/core_integration/index.html#multitenant-multi-core-extensions to understand how multiple cores is supposed to work. If your extension requires a core call then what that core is needs to be set at install time. Even in the dev environment you are setting a "Core" at install even though the dev environment doesn't really have a "Core". This will allow you to go through the code for the various "Core" scenarios.
How it works in the dev environment would be you simply mock the core responses to be whatever the real response would be from an actual Core given a particular call.
If you require additional assistance I recommend reaching out via support case.
Ok, thank you for that. Maybe there's a different solution if I give you my problem.
The problem i'm having is that my extension requires a core to function because i'm getting user information to send to my API. However, the testing environment does not have a core. I wanted to generate some mock user data that I can send my API whenever i detect there's no core. Maybe there's a stage varible that tells me if i'm in production or not?
—You can pull this from looking at your configuration Deploy Env: https://docs.q2developer.com/docs/guides/configuration.html#deploy-env see my answer here: https://community.q2developer.com/question/1574536779292217344/how-to-tell-which-environment-code-is-running-in
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