argocd sync app --dry-run should affect status and metrics of the apps?

[jsolana]

Hello! I’d like to hear your thoughts.

Currently, executing the command argocd app sync --dry-run affects both the application’s state and the internal metrics exposed by ArgoCD (eg: argocd_app_info).

The main issue is that if there are alerts based on these metrics, and the dry-run execution identifies an error (e.g., a change that violates a Kyverno policy or an invalid CRD schema), the application state changes to SyncErr. This also updates the metrics, which can potentially trigger alerts based on these metrics.

For example:

# alert manager alert definition
- alert: ArgoCDApplicationUnknown
  expr: sum by (cluster) (argocd_app_info{sync_status="Unknown"}) > 0
  for: 15m
...

Since the definition of a dry-run is to execute requests without persistence, I wonder if it makes sense to handle it in a way that ensures no changes are made.

Alternatively, adding a dry_run label to differentiate operational requests from dry-run requests could also be an option (a similar change has been proposed for kyverno link).

What do you think? Thanks!