Add support for identity tokens in config file.

Signed-off-by: Joffrey F <joffrey@docker.com>

docker/auth/auth.py

@@ -174,6 +174,15 @@ def parse_auth(entries, raise_on_error=False):
                     'Invalid configuration for registry {0}'.format(registry)
                 )
             return {}
+        if 'identitytoken' in entry:
+            log.debug('Found an IdentityToken entry for registry {0}'.format(
+                registry
+            ))
+            conf[registry] = {
+                'IdentityToken': entry['identitytoken']
+            }
+            continue  # Other values are irrelevant if we have a token, skip.
+
         if 'auth' not in entry:
             # Starting with engine v1.11 (API 1.23), an empty dictionary is
             # a valid value in the auths config.
@@ -182,13 +191,15 @@ def parse_auth(entries, raise_on_error=False):
                 'Auth data for {0} is absent. Client might be using a '
                 'credentials store instead.'
             )
-            return {}
+            conf[registry] = {}
+            continue
 
         username, password = decode_auth(entry['auth'])
         log.debug(
             'Found entry (registry={0}, username={1})'
             .format(repr(registry), repr(username))
         )
+
         conf[registry] = {
             'username': username,
             'password': password,

tests/unit/auth_test.py

@@ -460,4 +460,28 @@ class LoadConfigTest(base.Cleanup, base.BaseTestCase):
             json.dump(config, f)
 
         cfg = auth.load_config(dockercfg_path)
-        assert cfg == {}
+        assert cfg == {'scarlet.net': {}}
+
+    def test_load_config_identity_token(self):
+        folder = tempfile.mkdtemp()
+        registry = 'scarlet.net'
+        token = '1ce1cebb-503e-7043-11aa-7feb8bd4a1ce'
+        self.addCleanup(shutil.rmtree, folder)
+        dockercfg_path = os.path.join(folder, 'config.json')
+        auth_entry = encode_auth({'username': 'sakuya'}).decode('ascii')
+        config = {
+            'auths': {
+                registry: {
+                    'auth': auth_entry,
+                    'identitytoken': token
+                }
+            }
+        }
+        with open(dockercfg_path, 'w') as f:
+            json.dump(config, f)
+
+        cfg = auth.load_config(dockercfg_path)
+        assert registry in cfg
+        cfg = cfg[registry]
+        assert 'IdentityToken' in cfg
+        assert cfg['IdentityToken'] == token