fixup! syscontainers: add generation of an rpm

Atomic/syscontainers.py

@@ -966,7 +966,8 @@ def get_system_images(self, get_all=False, repo=None):
 
     def _is_service_active(self, name):
         try:
-            return self._systemctl_command("is-active", name, quiet=True).replace("\n", "") == "active"
+            ret = self._systemctl_command("is-active", name, quiet=True)
+            return ret and ret.replace("\n", "") == "active"
         except subprocess.CalledProcessError:
             return False
 
@@ -1510,6 +1511,9 @@ def generate_rpm(self, repo, name, image):
             spec_file = os.path.join(temp_dir, "container.spec")
             self._checkout(repo, name, image, 0, False, destination=rootfs, prefix=rpm_content)
 
+            if self.display:
+                return
+
             installed_files = None
             with open(os.path.join(rootfs, "info"), "r") as info_file:
                 info = json.loads(info_file.read())