Add support for custom go-jinja2 Extensions

[benedikt-bartscher]

Command

• check-image-updates
• delete
• deploy
• diff
• helm-pull
• helm-update
• list-images
• list-targets
• poke-images
• prune
• render
• seal
• validate
• version

Who are you?

No response

What do you want to do?

Currently there are only some predefined jinja2 extensions available.
It would be awesome if we could supply additional extensions via a cli flag or at best via deployment.yaml (multi-repo compatible).

Why do you need that?

Advanced templating

[netthier]

Also interested in something like this, but I do wonder how that would be implemented with Go being a compiled language.

[codablock]

Implementing this is not an issue, as Kluctl is using Python+Jinja2 under the hood for the templating. The thing that I'd be concerned of would be security, as Jinja2 extensions are basically plain Python code, allowing you to do all kinds of shenanigans.