Merge ~xnox/germinate:skip-unbuilt-packages into germinate:master

[Dimitri John Ledkov]

Skip updating metapackages for arches which are not built.

results in the following metapackages skipped, if not needed:

...
minimal/s390x: Skipping package ubuntu-minimal (metapackage)
standard/s390x: Skipping package ubuntu-standard (metapackage)
[s390x] Skipping ubuntu-desktop-minimal missing from dh_listpackages
[s390x] Skipping ubuntu-desktop missing from dh_listpackages
server/s390x: Skipping package ubuntu-server (metapackage)
...

[Jeremy Bícha (jbicha)]

Yes, this looks fine with https://launchpad.net/ubuntu/+source/ubuntu-meta/1.429

[Colin Watson (cjwatson)]

review: Needs Fixing

Unmerged commits

57f2868... by Dimitri John Ledkov on 2018-11-14

Skip updating metapackages for arches which are not built.

Signed-off-by: Dimitri John Ledkov <email address hidden>

diff --git a/germinate/scripts/germinate_update_metapackage.py b/germinate/scripts/germinate_update_metapackage.py
index d1b419f..a06ce89 100644
--- a/germinate/scripts/germinate_update_metapackage.py
+++ b/germinate/scripts/germinate_update_metapackage.py
@@ -289,6 +289,14 @@ def main(argv):
         for seed_name in output_seeds:
             meta_name = metapackage_name(structure, seed_name)
             metapackage_map[seed_name] = meta_name
+            active_packages = subprocess.check_output(
+                ['dpkg-architecture','-a%s' % architecture,
+                 '-c', 'dh_listpackages'],
+                stderr=subprocess.DEVNULL, universal_newlines=True)
+            if meta_name not in active_packages:
+                print("[%s] Skipping %s missing from dh_listpackages" %
+                      (architecture, meta_name))
+                continue
 
             output_filename = os.path.join(
                 options.outdir, '%s-%s' % (seed_name, architecture))