Add example for auth client

examples/collections_auth_client.py

+import logging
+
+import grpc
+from oauthlib.oauth2 import BackendApplicationClient
+
+from perxis.auth import OAuth2Plugin
+from perxis.collections_perxis.collections_pb2 import ListRequest
+from perxis.collections_perxis.collections_pb2_grpc import CollectionsStub
+
+
+def main():
+    client_id = 'YGPQSAUPgco4iTQxNejtXDjFVwPmYT3n'
+    client_secret = '_d6F-VlQGmcsU25AXIoCU4EU3v56-28P6jwUHkutg_hSPseConphyLs3F-Buuq1h'
+    token_url = 'https://adwz.auth0.com/oauth/token'
+    audience = 'some'
+
+    oauth2_plugin = OAuth2Plugin(
+        client=BackendApplicationClient(client_id=client_id),
+        client_secret=client_secret,
+        token_url=token_url,
+        audience=audience
+    )
+
+    call_credentials = grpc.metadata_call_credentials(oauth2_plugin, name='auth')
+    channel_credentials = grpc.ssl_channel_credentials()
+    composite_credentials = grpc.composite_channel_credentials(
+            channel_credentials, call_credentials
+    )
+    with grpc.secure_channel('envoy.perxis.pt.perx.ru:443', composite_credentials) as channel:
+        stub = CollectionsStub(channel)
+        collections = stub.List(ListRequest(space_id="c1mrvup3e6litup7tf0g", env_id="master"))
+        print(collections)
+
+
+if __name__ == '__main__':
+    logging.basicConfig(level=logging.INFO)
+    main()

perxis/auth.py

@@ -11,7 +11,7 @@ class OAuth2Plugin(grpc.AuthMetadataPlugin):
     _token = None
 
     def __init__(self, client: Type[Client], client_secret: str, token_url: str, audience: str,
-                 signature_header_key: str = 'Authorization', token_type: str = 'Bearer') -> None:
+                 signature_header_key: str = 'authorization', token_type: str = 'Bearer') -> None:
 
         self._client_secret = client_secret
         self._token_url = token_url
@@ -44,7 +44,7 @@ class OAuth2Plugin(grpc.AuthMetadataPlugin):
         if self._token is None:
             self._token = fetch_token()
 
-        if self._token.expires_at and self._token.expires_at < time.time():
+        if self._token['expires_at'] and self._token['expires_at'] < time.time():
             if 'refresh_token' in self._token:
                 self._token = refresh_token()
             else: