[yocto] why is "package-management" defined as a PACKAGE_GROUP?

[Robert P. J. Day]

On Sun, 17 Nov 2013, Paul Eggleton wrote:

> On Sunday 17 November 2013 06:30:01 Robert P. J. Day wrote:
> > On Sun, 17 Nov 2013, Paul Eggleton wrote:
> > > On Sunday 17 November 2013 04:19:19 Robert P. J. Day wrote:
> > > >   think i may have asked this once upon a time, but why, in
> > > >
> > > > core-image.bbclass, is there the line:
> > > >   PACKAGE_GROUP_package-management = "${ROOTFS_PKGMANAGE}"
> > > >
> > > > as i read it, package-management doesn't represent an actual
> > > > package group, but rather represents one of a number of
> > > > IMAGE_FEATURES that are processed explicitly in a .bbclass file,
> > > > like "debug-tweaks" or "read-only-rootfs". so what does the above
> > > > line mean?
> > >
> > > It's not a package group, but then neither are any of the things
> > > defined by PACKAGE_GROUP - that variable just specifies one or more
> > > packages to be installed when the specified item appears in
> > > IMAGE_FEATURES. Perhaps we should just rename the variable; it's a
> > > little more internal than some of the other variables we've renamed
> > > in the past.
> >
> >   oh, i realize it's not a package group, my point was that that line
> > seems entirely superfluous since, as with things like "debug-tweaks"
> > and "read-only-rootfs", that "image feature" is processed explicitly
> > within image.bbclass:
> >
> > # IMAGE_FEATURES may contain any available package group
> > IMAGE_FEATURES ?= ""
> > IMAGE_FEATURES[type] = "list"
> > IMAGE_FEATURES[validitems] += "debug-tweaks read-only-rootfs
> > package-management"
> >
> > # rootfs bootstrap install
> > ROOTFS_BOOTSTRAP_INSTALL = "${@base_contains("IMAGE_FEATURES",
> > "package-management", "", "${ROOTFS_PKGMANAGE_BOOTSTRAP}",d)}"
> >
> >   the simple solution would seem to be to just delete the line:
> >
> > PACKAGE_GROUP_package-management = "${ROOTFS_PKGMANAGE}"
> >
> > from core-image.bbclass since it's both unnecessary and misleading.
>
> It's not unnecessary - how else does the actual package manager make
> it into the image when package-management is in IMAGE_FEATURES?
>
> Now, this functionality should definitely be available from
> image.bbclass; this should get fixed with the rework I've proposed
> in the following bug:
>
> https://bugzilla.yoctoproject.org/show_bug.cgi?id=5424

  leaving aside the bug report, i am now hopelessly confused. are you
saying this line:

PACKAGE_GROUP_package-management = "${ROOTFS_PKGMANAGE}"

from core-image.bbclass is currently *necessary* to properly support
the image feature of "package-management" in core images? i don't see
how or why. using that logic, you'd also need lines of that form for
"read-only-rootfs" and "debug-tweaks", which certainly don't exist.

  are you sure you're answering the question i'm asking?

rday

p.s.  i just don't see how that line has any value based on a few
simple tests i ran. using dora to build for a beagle xm, i can display
some variables:

$ bb show -r core-image-base IMAGE_FEATURES
Parsing recipes..done.
IMAGE_FEATURES="debug-tweaks splash"
$ bb show -r core-image-base
EXTRA_IMAGE_FEATURES
Parsing recipes..done.
EXTRA_IMAGE_FEATURES="debug-tweaks"
$

which looks correct. now let's edit my local.conf and change:

EXTRA_IMAGE_FEATURES = "debug-tweaks"

to

EXTRA_IMAGE_FEATURES = "debug-tweaks package-management"

save, exit and verify:

$ bb show -r core-image-base IMAGE_FEATURES
Parsing recipes..done.
IMAGE_FEATURES="debug-tweaks splash package-management"
$ bb show -r core-image-base
EXTRA_IMAGE_FEATURES
Parsing recipes..done.
EXTRA_IMAGE_FEATURES="debug-tweaks package-management"

good. and now, let's edit core-image.bbclass and remove the line:

PACKAGE_GROUP_package-management = "${ROOTFS_PKGMANAGE}"

save, exit and test:

$ bb show -r core-image-base IMAGE_FEATURES
Parsing recipes..done.
IMAGE_FEATURES="debug-tweaks splash package-management"
$ bb show -r core-image-base
EXTRA_IMAGE_FEATURES
Parsing recipes..done.
EXTRA_IMAGE_FEATURES="debug-tweaks package-management"
$

  seems like the "package-management" image feature is being picked up
just fine.