Ensure Puppet can run even on PoC net setups

For `puppet apply` to run successfully, outputs of `hostname -f` and
`facter fqdn` must match. In a properly configured network environment
the outputs should always match, in PoC environment they might not. This
patch overrides the FQDN fact to the result of `hostname -f`, which will
make `puppet apply` succeed even in PoC environments where DNS is not
configured properly.

Change-Id: I0d63fb0b862f984a196ac01345c74b4e5378e8a8
Partial-Bug: #1447497

hot/software-config/elements/heat-config-puppet/install.d/hook-puppet.py

@@ -32,6 +32,16 @@ def prepare_dir(path):
         os.makedirs(path, 0o700)
 
 
+def get_hostname_f(log):
+    subproc = subprocess.Popen(['hostname', '-f'], stdout=subprocess.PIPE)
+    out = subproc.communicate()[0]
+    if subproc.returncode == 0:
+        return out.strip()
+    else:
+        log.warn("Failed to retrieve 'hostname -f' output")
+        return None
+
+
 def main(argv=sys.argv):
     log = logging.getLogger('heat-config')
     handler = logging.StreamHandler(sys.stderr)
@@ -53,6 +63,10 @@ def main(argv=sys.argv):
     facts = {}
     hiera = {}
 
+    fqdn = get_hostname_f(log)
+    if fqdn:
+        facts['FACTER_fqdn'] = fqdn
+
     for input in c['inputs']:
         input_name = input['name']
         input_value = input.get('value', '')