Helm diff plugin doesn't work with dependencies charts

[firehist]

Hello everybody,

First of all, thanks for the work 👏💪

I have a chart which use an other chart as a dependency.
When I override values for the dependency chart, the diff doesn't output any changes incoming, which is different from the upgrade command which applies well the changes.

Does the dependencies are handled by this awesome plugin?

To help the investigations, I created a simple repository to show the structure:
https://github.com/firehist/helm-diff-dependencies

Here are versions:

➜ helm3 version
version.BuildInfo{Version:"v3.5.0", GitCommit:"32c22239423b3b4ba6706d450bd044baffdcf9e6", GitTreeState:"clean", GoVersion:"go1.15.6"

➜ kubectl version
Client Version: version.Info{Major:"1", Minor:"16", GitVersion:"v1.16.0", GitCommit:"2bd9643cee5b3b3a5ecbd3af49d09018f0773c77", GitTreeState:"clean", BuildDate:"2019-09-18T14:36:53Z", GoVersion:"go1.12.9", Compiler:"gc", Platform:"darwin/amd64"}
Server Version: version.Info{Major:"1", Minor:"18+", GitVersion:"v1.18.20-gke.501", GitCommit:"de876a981b936ce528482c45794fb1dfc5005042", GitTreeState:"clean", BuildDate:"2021-06-25T02:54:31Z", GoVersion:"go1.13.15b4", Compiler:"gc", Platform:"linux/amd64"}

helm-diff-dependencies on  main
➜ helm3 plugin list
NAME       	VERSION   	DESCRIPTION
2to3       	0.8.0     	migrate and cleanup Helm v2 configuration and releases in-place to Helm v3
diff       	3.1.3     	Preview helm upgrade changes as a diff
mapkubeapis	0.0.15    	Map release deprecated Kubernetes APIs in-place

Thanks a lot.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[mahgo]

This is something that would be great to have fixed.

[mumoshu]

@firehist @mahgo Hey! Thanks for reporting. Although I was able to reproduce the exact issue, I'm not sure how this can be fixed.

helm-diff internally uses helm template(or helm upgrade --dry-run if #330 is enabled) to render the manifests from the chart. FWICS from my own test result, neither helm template nor helm upgrade --dry-run is unable to take the subchart values into account.

Would you mind confirming?

[mumoshu]

@firehist I've tried installing your example and run the below:

$ helm diff upgrade foo ./helm-diff-dependencies --set argo-cd.nameOverride=testtest

This did show a lot of diff due to changes in metadata.name of every resource in the argo-cd dependency:

https://gist.github.com/mumoshu/325631dd11e3fbd1e6d87b37537bcf37

All this seems to imply that it just works, correctly showing diff on the dependency.

I've tried it with both helm 3.5.3 and 3.7.2, with helm-diff 3.1.3 and the edge version of helm-diff build from the current master.

[mumoshu]

@mahgo Hey! What do you mean by "fixed" here? Did you actually verify that it didn't work as intended for you? Then, would you mind sharing your chart and the command you used to install and diff the release, for reproduction?

[mahgo]

@mumoshu I guess I didn't consider that handling dependency charts might be out of the scope of this plugin. If this is the case then it might be worth adding to the readme etc.

The main use case for me and this plugin so far has been to determine if upgrading a chart is needed or not.

[mumoshu]

@mahgo Just to be clear, are you basically saying you didn't actually try it? Then it's okay.

helm-diff upgrade should be able to show diff for any helm upgade. As long as helm upgrade supports dependencies, helm-diff upgrade should also support dependencies. Shouldn't that be straightforward enough? 🤔

[mahgo]

@mumoshu That's correct, I have not tried the given repository. However I have experienced this problem myself.

[mumoshu]

// I just wanted to know who had real issue(s), because that's required in order to "fix" something.

[mumoshu]

@mahgo I'd appreciate it if you could give me an example for reproduction, as I couldn't reproduce it. To be extra sure, are you sure how you can set values for sub-charts?