Snippets for Fedora CoreOS

[elemental-lf]

Feature Request

Feature

Is there any interest in bringing back the snippets feature for Fedora CoreOS? As far as I could determine the original implementation was dropped because of changes in the transpiler API.

I find the snippets feature invaluable because it keeps the changes to my fork of typhoon to a minimum which helps with upstream merges. Also, bare-metal environments tend to be less homogeneous than cloud environments and things like static IP addresses are more common, too.

I have a proof-of-concept implementation for bare-metal that uses the Ignition feature ignition.config.merge (was ignition.config.append in previous versions of Ignition) to merge the snippets into the main Ignition configuration. The snippets are first transpiled to JSON individually and then added in-line as BASE64 encoded data URLs. This seems to work so far but needs further testing.

If there is interest I'd prepare a pull-request for bare-metal. I still would need to figure out how to test these changes as my test bed setup might not be compatible with upstream.

[dghubble]

Snippets were developed to create a mechanism for additively merging Container Linux Configs through terraform-provider-ct and initial Fedora CoreOS support was added.

Fedora CoreOS snippets will be added there too, but likely after the current major items (v1.18, hyperkube, and initial Fedora CoreOS availability on platfroms). The feature is used across platforms (beyond just bare-metal). Typhoon docs kept a placeholder for Fedora CoreOS snippets to indicate they're on the roadmap.

[elemental-lf]

Note: snippets will be ignored with Fedora CoreOS and listing them as UNSUPPORTED in the documentation didn't lead me to believe that this feature is still on the roadmap so I searched for an alternative. But it is good to know. Thank you for clearing this up. If anyone needs a stop-gap measure for the time being please contact me directly I'll then point you to the code, I still need to publish it.