some style changes, some pylint, be less noisy

this changes url_map to a list and adds 'required' information.
 * If we've not already found an entry, and this is required,
   then debug log (ie, this is just not GCE).
 * if we already found an entry and this is required: warn

split the keys fixing out of the loop.

1 files changed, 44 insertions, 21 deletions

diff --git a/cloudinit/sources/DataSourceGCE.py b/cloudinit/sources/DataSourceGCE.py
index e2be15b0..c993293f 100644
--- a/cloudinit/sources/DataSourceGCE.py
+++ b/cloudinit/sources/DataSourceGCE.py
@@ -51,37 +51,60 @@ class DataSourceGCE(sources.DataSource):
         # GCE metadata server requires a custom header since v1
         headers = {'X-Google-Metadata-Request': True}
 
-        url_map = {
-            'instance-id': self.metadata_address + 'instance/id',
-            'availability-zone': self.metadata_address + 'instance/zone',
-            'public-keys': self.metadata_address + 'project/attributes/sshKeys',
-            'local-hostname': self.metadata_address + 'instance/hostname',
-            'user-data': self.metadata_address + 'instance/attributes/user-data',
-        }
+        # url_map: (our-key, path, required)
+        url_map = [
+            ('instance-id', 'instance/id', True),
+            ('availability-zone', 'instance/zone', True),
+            ('local-hostname', 'instance/hostname', True),
+            ('public-keys', 'project/attributes/sshKeys', False),
+            ('user-data', 'instance/attributes/user-data', False),
+        ]
 
         # if we cannot resolve the metadata server, then no point in trying
         if not util.is_resolvable(self.metadata_address):
-            LOG.debug('{0} is not resolvable'.format(self.metadata_address))
+            LOG.debug("%s is not resolvable", self.metadata_address)
             return False
 
         # iterate over url_map keys to get metadata items
-        for mkey in url_map.iterkeys():
+        found = False
+        for (mkey, path, required) in url_map:
             try:
-                resp = url_helper.readurl(
-                    url=url_map[mkey], headers=headers)
+                resp = url_helper.readurl(url=self.metadata_address + path,
+                                          headers=headers)
                 if resp.code == 200:
-                    if mkey == 'public-keys':
-                        pub_keys = [self._trim_key(k) for k in resp.contents.splitlines()]
-                        self.metadata[mkey] = pub_keys
-                    else:
-                        self.metadata[mkey] = resp.contents
+                    found = True
+                    self.metadata[mkey] = resp.contents
                 else:
-                    self.metadata[mkey] = None
+                    if required:
+                        msg = "required url %s returned code %s. not GCE"
+                        if not found:
+                            LOG.debug(msg, path, resp.code)
+                        else:
+                            LOG.warn(msg, path, resp.code)
+                        return False
+                    else:
+                        self.metadata[mkey] = None
             except url_helper.UrlError as e:
+                if required:
+                    msg = "required url %s raised exception %s. not GCE"
+                    if not found:
+                        LOG.debug(msg, path, e)
+                    else:
+                        LOG.warn(msg, path, e)
+                    return False
+                msg = "Failed to get %s metadata item: %s."
+                if found:
+                    LOG.warn(msg, path, e)
+                else:
+                    LOG.debug(msg, path, e)
+
                 self.metadata[mkey] = None
-                LOG.warn('Failed to get {0} metadata item. Reason {1}.'.format(
-                    mkey, e))
-        return True
+
+        if self.metadata['public-keys']:
+            lines = self.metadata['public-keys'].splitlines()
+            self.metadata['public-keys'] = [self._trim_key(k) for k in lines]
+
+        return found
 
     @property
     def launch_index(self):
@@ -94,7 +117,7 @@ class DataSourceGCE(sources.DataSource):
     def get_public_ssh_keys(self):
         return self.metadata['public-keys']
 
-    def get_hostname(self, fqdn=False):
+    def get_hostname(self, fqdn=False, _resolve_ip=False):
         return self.metadata['local-hostname']
 
     def get_userdata_raw(self):