Add a openstack specific datasource

Openstack has a unique derivative datasource that is gaining usage.
Previously the config drive datasource provided part of this functionality
as well as the ec2 datasource, but since new functionality is being added
to openstack's special datasource it seems beneficial to combine the used
parts into a new datasource just made for handling openstack deployments
that use the openstack metadata service (possibly in combination with the
ec2 metadata service).

This patch factors out the common logic shared between the config drive
and the openstack metadata datasource and places that in a shared helper
file and then creates a new openstack datasource that readers from the
openstack metadata service and refactors the config drive datasource to
use this common logic.

1 files changed, 7 insertions, 20 deletions

diff --git a/cloudinit/ec2_utils.py b/cloudinit/ec2_utils.py
index 7f4c0443..a7c9c9ab 100644
--- a/cloudinit/ec2_utils.py
+++ b/cloudinit/ec2_utils.py
@@ -16,12 +16,9 @@
 #    You should have received a copy of the GNU General Public License
 #    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-import httplib
-from urlparse import (urlparse, urlunparse)
-
 import functools
+import httplib
 import json
-import urllib
 
 from cloudinit import log as logging
 from cloudinit import url_helper
@@ -40,16 +37,6 @@ def maybe_json_object(text):
     return False
 
 
-def combine_url(base, add_on):
-    base_parsed = list(urlparse(base))
-    path = base_parsed[2]
-    if path and not path.endswith("/"):
-        path += "/"
-    path += urllib.quote(str(add_on), safe="/:")
-    base_parsed[2] = path
-    return urlunparse(base_parsed)
-
-
 # See: http://bit.ly/TyoUQs
 #
 class MetadataMaterializer(object):
@@ -121,14 +108,14 @@ class MetadataMaterializer(object):
         (leaves, children) = self._parse(blob)
         child_contents = {}
         for c in children:
-            child_url = combine_url(base_url, c)
+            child_url = url_helper.combine_url(base_url, c)
             if not child_url.endswith("/"):
                 child_url += "/"
             child_blob = str(self._caller(child_url))
             child_contents[c] = self._materialize(child_blob, child_url)
         leaf_contents = {}
         for (field, resource) in leaves.items():
-            leaf_url = combine_url(base_url, resource)
+            leaf_url = url_helper.combine_url(base_url, resource)
             leaf_blob = str(self._caller(leaf_url))
             leaf_contents[field] = self._decode_leaf_blob(field, leaf_blob)
         joined = {}
@@ -153,8 +140,8 @@ def _skip_retry_on_codes(status_codes, _request_args, cause):
 def get_instance_userdata(api_version='latest',
                           metadata_address='http://169.254.169.254',
                           ssl_details=None, timeout=5, retries=5):
-    ud_url = combine_url(metadata_address, api_version)
-    ud_url = combine_url(ud_url, 'user-data')
+    ud_url = url_helper.combine_url(metadata_address, api_version)
+    ud_url = url_helper.combine_url(ud_url, 'user-data')
     user_data = ''
     try:
         # It is ok for userdata to not exist (thats why we are stopping if
@@ -178,8 +165,8 @@ def get_instance_userdata(api_version='latest',
 def get_instance_metadata(api_version='latest',
                           metadata_address='http://169.254.169.254',
                           ssl_details=None, timeout=5, retries=5):
-    md_url = combine_url(metadata_address, api_version)
-    md_url = combine_url(md_url, 'meta-data')
+    md_url = url_helper.combine_url(metadata_address, api_version)
+    md_url = url_helper.combine_url(md_url, 'meta-data')
     caller = functools.partial(util.read_file_or_url,
                                ssl_details=ssl_details, timeout=timeout,
                                retries=retries)