Make --group mandatory

[slack]

We need to make sure folks who deploy more than one instance of a helm chart into a single namespace don't end up getting very confusing results.

For example, if I have two instances of redis-standalone in the default namespace and I use a simple label selector of provider=redis my application will be automatically load balanced between all redis instances.

We should probably make group=... parameter required.

[sgoings]

I think adding a required parameter reduces a bit of the magic that a helm install gives users. If at all possible, we should have default commands (with no parameters) that "just work."

[bgrant0607]

Why not just use separate namespaces?

Related: kubernetes/kubernetes#1698

[gabrtv]

Why not just use separate namespaces?

We do offer namespace parameterization. However, we also want to allow for multiple instances of a chart (Redis) to live in the same namespace. The group label convention allows for multiple providers to co-exist in the same namespace -- analogous to a tier label.

[technosophos]

I am not totally convinced that we need to make group mandatory for Helm to work. This imposes an unnecessary burden on the simple-case user. It also enforces a part of "our model" that not all users will find they want to participate in.

I'd rather develop more of a use case than rush to implement this as described here.

[bgrant0607]

I'm supportive of adding some automatic label management to Kubernetes.

kubernetes/kubernetes#15390

[mboersma]

The future of Helm is at kubernetes/helm. Helm Classic is in maintenance mode, so I'm closing this enhancement request.