Currently, we name RHEL versions in osbuild-composer in the following way: rhel-[MAJOR][MINOR]. For single-digit major or minor versions, this worked alright (albeit it was always a bit confusing from my point of view).

However, RHEL 8.10 and 10.0 are coming and parsing rhel-810 and rhel-100 will be quite cumbersome. Thus, we should switch to a dot notation: rhel-[MAJOR].[MINOR] RHEL 8.10 and 10.0 will thus be named rhel-8.10 and rhel-10.0.

Goal:

• Use dot notation (or any other way to explicitly separate major and minor version) internally in composer to avoid ambiguity.
• Make dot notation the default way to specify a RHEL version in all public APIs.
• Keep backward compatibility with the old notation: Specifying rhel-88 in the API must keep working after this change is implemented.

Acceptance Criteria:

• Our APIs accept the RHEL versions in the dot notation by default. This is also reflected in documentation. Use of the old notation is discouraged in the codebase and removed as much as possible.
• The APIs accept the old notation as well to keep backward compatibility. This is reasonably tested.

Open questions:

• Shall we allow rhel-810? We might want to keep this one as an exception, so already existing scripts don't break.
• Shall we allow rhel-100? I don't think so.