Support Kubernetes ConfigMaps as datasources about gomplate HOT 10 CLOSED

I'll work on this if you don't mind

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Ok thanks for the tips -- looks like https://github.com/kubernetes/client-go is what I want. I'll dabble with this when I get some time.

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The would make sense for Secrets probably, too.

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Thanks @rhuss - I'm not very familiar with Kubernetes, but looking at the API, this could be fairly easy to implement using an HTTP(S) datasource (see https://kubernetes.io/docs/api-reference/v1.5/#read-199 for example).

One thing I'm not sure about is authentication, though #115 went in recently which allows arbitrary headers to be sent (mostly for auth purposes).

I think a good start would be to try to see if something like this works:

(in.tmpl)

{{ (datasource "myconfigmap").data | toJSON }}

$ gomplate --datasource myconfigmap=http://my.kube.api.address/api/v1/namespaces/{namespace}/configmaps/myconfigmap -f in.tmpl

It'd probably be nicer to have simplified support, but hopefully this is a start! Can you try this out and let me know if it works? Or let me know if I'm way off and this makes no sense 😉

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Kubernetes comes with a full client API which you can use directly without going over HTTP. As this datasource is probably supposed to be used within a Kubernetes cluster, the API server can be easily used with a so called ServiceAccount, so there is not to worry much about authentication.

The use case I have in mind is agnostic of the API server's address as it is running from within the cluster (not from outside where it doesn't make much sense imo).

As seen also in the SO answer all connection parameters can be directly fetched from files which are installed by Kubernetes at fixed file locations within the container (so gomplate could simply pick them up there). The namespace can also be picked up directly (would have to check how, though). The only parameters left is then configmap name.

It''s not urgent, just wanted to open the issue more as reminder for a cool, unique feature ;-)

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That'd be great!

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Love this idea!

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@josledp thank you! That would be fantastic!

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Good man

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More than a year since there's been any activity, I'm going to close this issue for now.

While it would be interesting for gomplate to support ConfigMaps and Secrets directly, the usual pattern that I've seen is to mount the ConfigMap as a file inside the pod, and gomplate can read these files with no issue. I've seen gomplate used like this in a few cases.

If there is renewed interest, feel free to re-open the issue! Mostly I'm trying to clean up stale issues and PRs 😉

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