This would have been my thinking as. Add something like IMAGE_CREATE_FROM = 
"production-image" in your development-image recipe would go a long way.

+1 for Jan's suggestion.

Cedric

On Monday, August 27, 2018 at 10:29:35 AM UTC+2, Jan Kiszka wrote:
>
> On 2018-08-27 09:44, Claudius Heine wrote: 
> > On 2018-08-27 09:25, [ext] Claudius Heine wrote: 
> >> Hi Jan, 
> >> 
> >> On 2018-08-27 08:41, [ext] Jan Kiszka wrote: 
> >>> Hi all, 
> >>> 
> >>> I was wondering if / how we could model the increasingly common case 
> >>> of building very similar target images more efficiently. 
> >>> 
> >>> A devel image, e.g., likely consists of almost the same base package 
> >>> set as the release image. It may only add further packages and maybe 
> >>> replace very few (like customization packages). When building both, 
> >>> we could save time - specifically when doing cross - by bootstrapping 
> >>> the baseline only once. We already do that for the debootstrap step, 
> >>> but not yet for further packages. 
> >>> 
> >>> What do you think? And how could that be modeled from user 
> perspective? 
> >> 
> >> That is not very easy. 
> >> 
> >> A complex way this could be done by having a `common image` recipe 
> >> that depends on other image recipes to deploy their required package 
> >> list, 
> > 
> > What I meant by that is each image recipe writes its package list into 
> > its own text file in the 'deploy' directory. 
> > 
> >> then figure out the common dependencies of all of them and build the 
> >> custom image. 
> > 
> > s/custom/common/ 
> > 
> > Problem scenario here is: 
> > 
> >   Image A: depends on A which depends on D 
> >   Image B: depends on B which depends on D 
> > 
> > Since D is not named in any recipes, but should be installed in the 
> > `common image` as automatically selected package (not as manual). This 
> > scripting is a bit tricky. 
> > 
> >> Then those other image recipes depend of the `common image` recipe in 
> >> turn to create it, copy it and base their own customizations on top. 
> >> 
> >>  From a user perspective they would have to add their image recipes 
> >> into a global variable or bbappend, so that is available in the 
> >> `common image` recipe. The rest could be done in the image classes. 
> >> 
> >> Cheers, 
> >> Claudius 
> > 
>
> Hmm, I'm not seeing yet where the complication could come from. I would 
> have expected the following: 
>
> - write a new image recipe include that takes a preexisting image in 
>    form of a rootfs as input (rather than using setup_root_file_system) 
>
> - create specialized images on top of that which depend on some base 
>    image recipe as well as additional IMAGE_INSTALL recipes and may come 
>    with own IMAGE_PREINSTALLs (always on top of base images) 
>
> - push all common IMAGE_PREINSTALLs into base image recipes, same for 
>    all IMAGE_INSTALLs 
>
> And done. What am I missing? 
>
> Jan 
>