Long ago Kubernetes service names were restricted to 53 characters. More recent versions of Kubernetes allow longer service names, though there was a time that some users were using the older version of Kubernetes so we couldn't relax the constraint. We can probably relax that constraint now.

Which parts would have to be updated to relax the constrain?

Not sure if much has changed since #1560, but looks like that bumped it last time.

Here is where it resides today.

@bacongobbler shouldn't helm be up to 63 characters as weel?

Because when a chart is create it limits to 63 characters in the _helpers.tpl file.

See the comment in the code linked above.

// As of Kubernetes 1.4, the max limit on a name is 63 chars. We reserve 10 for
// charts to add data. Effectively, that gives us 53 chars.
// See #1528

We upgraded to Helm3 but now helm render fails with "release name exceeds max length of 53" error. What is the resolution here? Is Helm planning to increase the character limit?

It's not perfect, but we run our release names through a little bash function ahead of time:

function normalizeHelmReleaseName {
    # See https://github.com/helm/helm/issues/6006#issuecomment-553184466
    if [ ${#1} -gt 53 ]; then
        printf "%s-%s" $(echo -n $1 | cut -c -44) $(echo -n $1 | sha256sum | cut -c -8)
    else
        echo -n $1
    fi
}

@vaibhav-si we'd welcome PRs to increase the character limit to whatever's reasonable in more recent Kubernetes versions. It's open source! Feel free to contribute.

@bacongobbler I would love to contribute, is there a documented process for contributing? How does the build system work?

https://helm.sh/docs/community/developers/

https://github.com/helm/helm/blob/master/CONTRIBUTING.md

See the comment in the code linked above.

// As of Kubernetes 1.4, the max limit on a name is 63 chars. We reserve 10 for
// charts to add data. Effectively, that gives us 53 chars.
// See #1528

What is the rationale behind choosing 53 chars for release_name and 10 for chart data

With recent versions of kubernetes supporting 253 characters what should be this ratio now?

See the comment in the code linked above.

// As of Kubernetes 1.4, the max limit on a name is 63 chars. We reserve 10 for
// charts to add data. Effectively, that gives us 53 chars.
// See #1528

What is the rationale behind choosing 53 chars for release_name and 10 for chart data

With recent versions of kubernetes supporting 253 characters what should be this ratio now?

@bacongobbler could you answer this?

I think I already answered that question earlier in the thread. #6006 (comment)

hi @bacongobbler I'd love to fix that as my first PR here. The goal is change to 243 and keep 10 for chart data,right ?

Just to be sure, I would advise doing some testing (and some digging in kubernetes/kubernetes to make sure that assumption of 253 characters for a service name still holds true today). But assuming that works, then yes, bumping the release name maximum character length to 243 characters should be fine.

@renatosuero It seems to be 253 alright: https://kubernetes.io/docs/concepts/overview/working-with-objects/names

You would need to take into account that a release is stored as a Secret/ConfigMap in the cluster with the following nomenclature for its name: sh.helm.release.v1.<release_name>.v1. This means then it would be 253 -22 (prefix + postfix of name) = 231 characters

@hickeyma thanks, I was checking the kubernetes repository and I found that.
https://github.com/kubernetes/kubernetes/blob/cfc845be63e88451779d209ecebbed81af54cdfa/staging/src/k8s.io/apimachinery/pkg/labels/selector_test.go#L321

https://github.com/kubernetes/kubernetes/blob/aadaa5d6a917fcb354bce80a0bd1830c95cfbcc3/staging/src/k8s.io/apimachinery/pkg/util/validation/validation.go#L202

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