Re: Some random musings on ostree vs OCI/Docker format

[Colin Walters <walters verbum org>]

Grr, hit ctrl-retrun accidentally.

On Tue, Aug 9, 2016, at 08:36 AM, Colin Walters wrote:

> So I see a few  ...

options.  One thing that would be fairly straightforward for the baseos
case is to define a mapping between OCI "registries" and OSTree repos. 
The first step is to basically put either an ostree "from scratch" static
delta or an archive repo *inside* an OCI layer.  Then, new commits would
be a new image (not a new layer on top of the previous).

However, we would define a mapping for static deltas that could also
be packed into OCI layers.  This would get into the "discovery" problem -
how do we name the delta - I think we'd likely run into image
name length restrictions if we based it on checksums.  Perhaps we could
just go with abbreviated checksums, or alternatively, use the checksum
of the *delta*, and add extra metadata inside the manifest for *new*
images that links to deltas from previous ones.

Flatpak-like container tools could reuse some of this encapsulation in the short
term, or consider moving towards using the format directly (although
with concomitant loss in things like GPG signatures until that becomes standard in OCI0.
Although for Flatpak, the separate runtime/app distinction that is *dynamically*
linked means it also wouldn't be using the OCI layering.