Check file path before Initialize crd

[my-git9]

What type of PR is this?
/kind bug

What this PR does / why we need it:
1.When we run karmadactl init --kube-image-registry=registry.cn-hangzhou.aliyuncs.com/google_containers --crds /root/crds.tar.gz
2.If the crds dir do not has patches or bases, like

$ ls crds
crd.yaml  net.yaml

3. The output:

4. What do we expect:
   Command output file does not exist, and exit

Which issue(s) this PR fixes:
Fixes #

Special notes for your reviewer:
The test result:

Does this PR introduce a user-facing change?:

Check if the file path exists before Initialize crd.

[my-git9]

/cc @lonelyCZ @RainbowMango

[my-git9]

/cc @prodanlabs

[my-git9]

/assign @prodanlabs

[karmada-bot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by:
To complete the pull request process, please ask for approval from prodanlabs after the PR has been reviewed.

The full list of commands accepted by this bot can be found here.

Needs approval from an approver in each of these files:

• pkg/karmadactl/cmdinit/OWNERS

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[RainbowMango]

Sorry for letting this sit.
I think this is a reasonable improvement. @my-git9 would you like to rebase and re-open this PR? You can just assign it to me.

[my-git9]

Sorry for letting this sit. I think this is a reasonable improvement. @my-git9 would you like to rebase and re-open this PR? You can just assign it to me.

Sure, thanks

[my-git9]

/assign @RainbowMango

[RainbowMango]

I'll try to get back on this by this week.
@chaosi-zju Would you like to take a look?

[chaosi-zju]

Hello, thank you for your important commit! Review is ongoing, and my viewpoint just for reference only.

[chaosi-zju]

Hello, I wanna why if err != nil && !os.IsNotExist(err), we not return the err but return nil?

how about like this:

func PathExist(path string) error {
    _, err := os.Stat(path)
    if err != nil && !os.IsExist(err) {
        return err
    }
    return nil
}

[chaosi-zju]

Hi, have you tested if this dir is just a empty dir, if there is any other unexpected failure?

[chaosi-zju]

ditto

[RainbowMango]

Just looked into it.
The root cause seems that the filepath.Walk might arise an error(like no such file or directory) when visiting the path(in this case it is the non-exist /crds/bases), this error should be handled but accidentally be ignored at here:

karmada/pkg/karmadactl/cmdinit/utils/util.go

Line 133 in ef87bd2

if !info.IsDir() {

.

Currently, we lack an efficient way to validate a specified crd.tar.gz, this approach just focuses on checking if crds/base and crds/patches exist or not, it's a little bit restrictive. E.g. what if these paths exist but don't have the expected files? (I didn't test it, just a guess, it will make things worse, because it may mask the issue and allow the entire installation process to continue, giving the user a false impression of successful installation, which I mean it is worse.)

So, my opinion is either to establish a comprehensive validation mechanism for the crds.tar.gz based on this issue or temporarily postpone this issue.

[my-git9]

Yes, it seems that this PR has a lot of limitations

[RainbowMango]

/close

Please reopen it if you think we still need it.

[karmada-bot]

@RainbowMango: Closed this PR.

In response to this:

/close

Please reopen it if you think we still need it.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.