Use the GCE short hostname.

Google Compute Engine fqdn hostnames are usually longer than 64 characters.
This causes issues with many tools (often Java based).

Note that per gethostname(2):
  POSIX.1-2001 guarantees that "Host names (not including the terminating null
  byte) are limed to HOST_NAME_MAX bytes".  On Linux, HOST_NAME_MAX is defined
  with the value 64.

LP: #1383794

3 files changed, 7 insertions, 4 deletions

diff --git a/ChangeLog b/ChangeLog
index bd209fce..400e51f3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -16,6 +16,7 @@
    types
  - Update to use newer/better OMNIBUS_URL for chef module
  - GCE: Allow base64 encoded user-data (LP: #1404311) [Wayne Witzell III]
+ - GCE: use short hostname rather than fqdn (LP: #1383794) [Ben Howard]
 0.7.6:
  - open 0.7.6
  - Enable vendordata on CloudSigma datasource (LP: #1303986)
diff --git a/cloudinit/sources/DataSourceGCE.py b/cloudinit/sources/DataSourceGCE.py
index 92e5a28e..f877b3d1 100644
--- a/cloudinit/sources/DataSourceGCE.py
+++ b/cloudinit/sources/DataSourceGCE.py
@@ -124,7 +124,8 @@ class DataSourceGCE(sources.DataSource):
         return self.metadata['public-keys']
 
     def get_hostname(self, fqdn=False, _resolve_ip=False):
-        return self.metadata['local-hostname']
+        # GCE has long FDQN's and has asked for short hostnames
+        return self.metadata['local-hostname'].split('.')[0]
 
     def get_userdata_raw(self):
         return self.metadata['user-data']
diff --git a/tests/unittests/test_datasource/test_gce.py b/tests/unittests/test_datasource/test_gce.py
index 89251b0e..06050bb1 100644
--- a/tests/unittests/test_datasource/test_gce.py
+++ b/tests/unittests/test_datasource/test_gce.py
@@ -99,7 +99,8 @@ class TestDataSourceGCE(test_helpers.HttprettyTestCase):
             body=_new_request_callback())
         self.ds.get_data()
 
-        self.assertEqual(GCE_META.get('instance/hostname'),
+        shostname = GCE_META.get('instance/hostname').split('.')[0]
+        self.assertEqual(shostname,
                          self.ds.get_hostname())
 
         self.assertEqual(GCE_META.get('instance/id'),
@@ -126,8 +127,8 @@ class TestDataSourceGCE(test_helpers.HttprettyTestCase):
         self.assertEqual(GCE_META_PARTIAL.get('instance/id'),
                          self.ds.get_instance_id())
 
-        self.assertEqual(GCE_META_PARTIAL.get('instance/hostname'),
-                         self.ds.get_hostname())
+        shostname = GCE_META_PARTIAL.get('instance/hostname').split('.')[0]
+        self.assertEqual(shostname, self.ds.get_hostname())
 
     @httpretty.activate
     def test_metadata_encoding(self):