skaffold render output is not same as skaffold run manifests while using helm --post-renderer flag

[sev3ryn]

Expected behavior

skaffold render creates and displays the same manifests as will be deployed using skaffold run

Actual behavior

skaffold render - ignores --post-renderer helm flag, therefore post-rendering step is skipped while executing skaffold run it executes fine

Information

This behavior is related to the missing option for setting flags for helm template command (only install/upgrade) in the configuration which is executed during skaffold render

[briandealwis]

My inclination is to close this as working-as-intended. In all honesty, we can't really support the use of --post-renderer in the Helm install and upgrade flags. Skaffold already uses --post-renderer to support skaffold debug and may further broaden our use of --post-renderer.

@sev3ryn I am curious to know what kind of transformations you're performing with post-renderer.

[sev3ryn]

I'm using post-renderer in helm for two use cases:

1. To patch third-party helm charts with kustomize to add securityContext and set resources for those charts that don't have them.
2. To patch secret manifests by replacing the path to secret in Hashicorp Vault with an actual secret.

I wouldn't say that this is p1 issue, but implementing it will help a lot for debugging what is happening during skaffold run

[aaron-prindle]

@briandealwis did you have any opinions on whether it makes sense to add more generfal --post-deployment flag support for helm through the skaffold CLI or if it not feasible as currently skaffold uses the --post-deployment flags? Thanks.

[briandealwis]

Skaffold doesn't yet use --post-deployment, but it will. I think we can examine our deploy.helm.flags and daisy-chain to whatever is specified there. This is tracked in #6951.