Consider partitions as sources for configdrive if labelled correctly

This change removes the filtering of partitions from potential ConfigDrive
sources, if the LABEL of the partition is set to "config-2".

This is useful for a bare metal device. It may not have a separate device for
ConfigDrive, but instead have a ConfigDrive available on a partition.

ChangeLog

@@ -19,6 +19,8 @@
    'Recommends' in the debian/control.in [Vlastimil Holer]
  - if mount_info reports /dev/root is a device path for /, then convert
    that to a device via help of kernel cmdline.
+ - configdrive: consider partitions as possible datasources if they have
+   theh correct filesystem label. [Paul Querna]
 0.7.4:
  - fix issue mounting 'ephemeral0' if ephemeral0 was an alias for a
    partitioned block device with target filesystem on ephemeral0.1.

cloudinit/sources/DataSourceConfigDrive.py

@@ -284,8 +284,10 @@ def find_candidate_devs():
     # followed by fstype items, but with dupes removed
     combined = (by_label + [d for d in by_fstype if d not in by_label])
 
-    # We are looking for block device (sda, not sda1), ignore partitions
-    combined = [d for d in combined if not util.is_partition(d)]
+    # We are looking for a block device or partition with necessary label or
+    # an unpartitioned block device.
+    combined = [d for d in combined
+                    if d in by_label or not util.is_partition(d)]
 
     return combined
 

tests/unittests/test_datasource/test_configdrive.py

@@ -285,10 +285,11 @@ class TestConfigDriveDataSource(MockerTestCase):
             self.assertEqual(["/dev/vdb", "/dev/zdd"],
                              ds.find_candidate_devs())
 
-            # verify that partitions are not considered
+            # verify that partitions are considered, but only if they have a label.
             devs_with_answers = {"TYPE=vfat": ["/dev/sda1"],
                 "TYPE=iso9660": [], "LABEL=config-2": ["/dev/vdb3"]}
-            self.assertEqual([], ds.find_candidate_devs())
+            self.assertEqual(["/dev/vdb3"],
+                              ds.find_candidate_devs())
 
         finally:
             util.find_devs_with = orig_find_devs_with