Prefix CMP env var names

[crenshaw-dev]

Summary

When a user sets an env var in a plugin-type Application spec, that env var is set for CMP manifest generation. We should prefix those env vars to limit what the user can change.

Motivation

CMPs involve plugin-author-defined tools which may be affected in various ways by env vars. By adding a prefix, we can make sure Application authors can't negatively impact the behavior of the CMP tools.

Proposal

We should prefix env vars with ARGOCD_USER_. This will be a breaking change, so we should do it on a major version and communicate clearly that plugin authors will have to update their plugins if it expects certain env vars.

[thatsmydoing]

Is there a way for plugins to check which version of argocd is running to decide what env var to use? Or is it expected to just try both variable names?

[crenshaw-dev]

@thatsmydoing it's currently expected to try both. If that's causing trouble, lmk, and we can try to figure something else out!

[thatsmydoing]

Got it, the changelog suggested updating plugins but not how to be compatible with previous versions so just wanted to confirm what the suggested approach is.