Re-sending one more time, since I did not find the message on aeolus-devel mailing list after sending it. Please, see below: -------- Original Message -------- Subject: RFC: Image versioning / Component Outline versioning Date: Fri, 14 Dec 2012 14:58:00 +0100 From: Jaromír Coufal <jcoufal(a)redhat.com&gt; To: aeolus-devel <aeolus-devel(a)lists.fedorahosted.org&gt; CC: mtaylor(a)redhat.com, Angus Thomas <athomas(a)redhat.com&gt;, Jan Provazník <jprovazn(a)redhat.com&gt;, Scott Seago <sseago(a)redhat.com&gt;, Michael Orazi <morazi(a)redhat.com&gt;, jguiditt(a)redhat.com, imcleod(a)redhat.com, Hugh Brock <hbrock(a)redhat.com&gt;, Matthew Wagner <mawagner(a)redhat.com&gt; Gentlemen, In last couple of days, even on technical cabal, we had been dealing with following issue, which is still a little bit unclear. I would like to ask all of you for comments regarding versioning images and their component outlines. The question is: * Do we want to allow user to edit Component Outline (Image XML) which brings functionality for advanced image versioning? * And if so, on which level? Situation is following: * In Component Outline you can specify * OS (Fedora, Ubuntu, ...) * Architecture (x86_64,...) * Packages * Running services Arguments for: * User can change image specification in the future (e.g. he can add new packages, new services, etc.) * User can return back to older versions * We are adding advanced functionality for the user (giving him more freedom) * With changing just the specification, we don't have to change references in AppForm Blueprints (Deployables) since they keep still the same Image ID. Arguments against: * With changing image specification, the whole object changes (Is it still the same object with different specification? E.g. different OS, architecture,...?) * If it is still the same object, what change makes it enough different to become different one (changing OS? architecture? or what packages?) * By changing image specification we can break other dependencies in related AppForm Blueprints (Deployables), which might depend on certain package, service, etc. * If we allow Image versioning, do we also want use to use older versions of the image as well? * With more freedom becomes bigger responsibility to user and higher potential to break things down * We are complicating scenarios for user (If user wants change, he can do it by cloning image and changing just what he needs) Thank you for all of your ideas -- Jarda -- Jaromír Coufal Interaction Designer Red Hat Czech s.r.o. Mobile: +420 724 595 508 E-mail: jcoufal(a)redhat.com IRC: jcoufal at #cloudforms-ui, #aeolus, #brno