Avoid prometheus metrics explosion

Openstacksdk reports metrics for prometheus and adds an endpoint-label
containing the full url of every request. In case the endpoints
contain query strings this can easily cause metric explosion. To fix
this we can parse the url and strip the query string.

Change-Id: Ief3c3981a039b3ae38eeaeccd1fb70e974c94082

openstack/proxy.py

@@ -11,6 +11,7 @@
 # under the License.
 
 import urllib
+from urllib.parse import urlparse
 
 try:
     import simplejson
@@ -226,10 +227,13 @@ class Proxy(adapter.Adapter):
             url = response.request.url
         if response is not None and not method:
             method = response.request.method
+        parsed_url = urlparse(url)
+        endpoint = "{}://{}{}".format(
+            parsed_url.scheme, parsed_url.netloc, parsed_url.path)
         if response is not None:
             labels = dict(
                 method=method,
-                endpoint=url,
+                endpoint=endpoint,
                 service_type=self.service_type,
                 status_code=response.status_code,
             )