accept files in Flux CLI's 'push artifact' subcommand

[developer-guy]

Flux CLI takes a --path parameter that can be used to specify a directory where the Kubernetes manifests are located to push manifests to an OCI registry. Still, some projects keep all the manifests within the same file; for example, Kyverno keeps all the deployment resources on a single file, install.yaml. In that case, to push this manifest, I need to create a directory, copy this file to that directory and tell Flux to look at that directory. To avoid that, maybe Flux CLI can also accept a flag called --file to look for a file instead of a directory.

[stefanprodan]

We could make --path accept a file path, copy the file to /tmp/random-dir/ then package it as if we were running flux push artifact --path ./ from inside the tmp dir.

[developer-guy]

Yeah, that makes a lot of sense to me. I'm willing to do this. May I do it?

[stefanprodan]

Sure, please create an issue for both build and push in flux2. First step is to add file support here https://github.com/fluxcd/pkg/tree/main/oci/client and tests. Thanks!