Use helm show chart to identify chart version

[felipecrs]

Test:

$ helm fetch https://github.com/jenkinsci/helm-charts/releases/download/jenkins-4.2.6/jenkins-4.2.6.tgz
$ mv -f jenkins-4.2.6.tgz jenkins.tgz

$ helmfile sync
UPDATED RELEASES:
NAME      CHART           VERSION
jenkins   ./jenkins.tgz          

$ ./helmfile sync
UPDATED RELEASES:
NAME      CHART           VERSION
jenkins   ./jenkins.tgz     4.2.6

[felipecrs]

I will fix these issues.

[yxxhero]

Good idea.

[felipecrs]

Ok, both lint and tests should pass now. I'm not sure about the approach I used to avoid tests from failing, Golang isn't my best skill. So, if you think it's easier/faster to just fixup the code by yourself, feel totally free (otherwise it's totally ok to provide comments as well).

[yxxhero]

@felipecrs please fix issue.

[felipecrs]

@yxxhero I fixed the GCI error but I can't identify what's wrong with the tests.

[yxxhero]

@felipecrs please fix ci issue. Do you need help?

[yxxhero]

@felipecrs from origin code. It can't get chart version. but your code can do it. so you should change the test case log output.

[felipecrs]

@yxxhero I think I fixed it now in a cleaner way.

[yxxhero]

@felipecrs Please add some test.

[felipecrs]

@yxxhero I added one test, let me know if it's enough.

[yxxhero]

@felipecrs last step: please squash your commits. It's so much.

[felipecrs]

@yxxhero done.

[yxxhero]

LGTM

[yxxhero]

@mumoshu

[mumoshu]

I think this is our first attempt to use Go helm pkg directly rather than calling out to the helm command.
I don't know if it works out in the long term but it would be worth trying.

[mumoshu]

@yxxhero If this is okay, we might be able to replace every invocation to helm command with the respective call to helm.sh/helm/v3/pkg/whatever structs and functions. That would free our users from being required to make Helmfile and Helm versions in-sync. WDYT?

[yxxhero]

This is equivalent to not relying on the help binary, which should require many changes and can be optimized in the future. @mumoshu

[mumoshu]

LGTM. Thanks a lot for your efforts! This is awesome.

[felipecrs]

Thank you too! :)