Look at the v1 endpoint for the GCE metadata server

We are updating all uses of the legacy GCE metadata server endpoints
(0.1 and v1beta) to use the current endpoint.

oauth2client/contrib/gce.py

@@ -32,8 +32,8 @@
 logger = logging.getLogger(__name__)
 
 # URI Template for the endpoint that returns access_tokens.
-META = ('http://metadata.google.internal/0.1/meta-data/service-accounts/'
-        'default/acquire{?scope}')
+META = ('http://metadata.google.internal/computeMetadata/v1/instance/'
+        'service-accounts/default/acquire{?scope}')
 
 
 class AppAssertionCredentials(AssertionCredentials):
@@ -84,7 +84,8 @@ def _refresh(self, http_request):
         """
         query = '?scope=%s' % urllib.parse.quote(self.scope, '')
         uri = META.replace('{?scope}', query)
-        response, content = http_request(uri)
+        response, content = http_request(
+            uri, headers={'Metadata-Flavor': 'Google'})
         content = _from_bytes(content)
         if response.status == 200:
             try:

tests/contrib/test_gce.py

@@ -66,11 +66,13 @@ def _refresh_success_helper(self, bytes_response=False):
         credentials.refresh(http)
         self.assertEquals(access_token, credentials.access_token)
 
-        base_metadata_uri = ('http://metadata.google.internal/0.1/meta-data/'
-                             'service-accounts/default/acquire')
+        base_metadata_uri = (
+            'http://metadata.google.internal/computeMetadata/v1/instance/'
+            'service-accounts/default/acquire')
         escaped_scopes = urllib.parse.quote(' '.join(scopes), safe='')
         request_uri = base_metadata_uri + '?scope=' + escaped_scopes
-        http.request.assert_called_once_with(request_uri)
+        http.request.assert_called_once_with(
+            request_uri, headers={'Metadata-Flavor': 'Google'})
 
     def test_refresh_success(self):
         self._refresh_success_helper(bytes_response=False)
@@ -158,8 +160,9 @@ def test_get_access_token(self):
         self.assertEqual(None, token.expires_in)
 
         http.request.assert_called_once_with(
-            'http://metadata.google.internal/0.1/meta-data/service-accounts/'
-            'default/acquire?scope=dummy_scope')
+            'http://metadata.google.internal/computeMetadata/v1/instance/'
+            'service-accounts/default/acquire?scope=dummy_scope',
+            headers={'Metadata-Flavor': 'Google'})
 
     def test_save_to_well_known_file(self):
         import os