NXPY-201: Allow more extensability of request_token()

Also simplified the `OAuth2Error` exception as the stacktrace was not useful.

examples/authentication.rst

@@ -62,7 +62,17 @@ Scenario 1: Generating a New Token
     authorization_response = req.url
 
     # Step 3, get the token
-    token = nuxeo.client.auth.request_token(authorization_response, code_verifier)
+    token = nuxeo.client.auth.request_token(
+        code_verifier=code_verifier,
+        authorization_response=authorization_response,
+    )
+
+    # Step 3, another possibility when you already parsed *authorization_response* and know the *code*
+    token = nuxeo.client.auth.request_token(
+        code_verifier=code_verifier,
+        code=code,
+        state=state,
+    )
 
 
 Scenario 2: Using an Existing Token

nuxeo/auth/oauth2.py

@@ -4,7 +4,7 @@
 from time import time
 
 from authlib.common.security import generate_token
-from authlib.integrations.base_client.errors import OAuthError
+from authlib.integrations.base_client.errors import AuthlibBaseError
 from authlib.integrations.requests_client import OAuth2Session
 from authlib.oauth2.rfc7636 import create_s256_code_challenge
 
@@ -77,9 +77,9 @@ def _request(self, method, *args, **kwargs):
         """Make a request with the OAuthlib client and shadow exceptions."""
         try:
             return method(*args, **kwargs)
-        except OAuthError as exc:
+        except AuthlibBaseError as exc:
             # TODO NXPY-129: Use raise ... from None
-            raise OAuth2Error(exc.error, exc.description)
+            raise OAuth2Error(exc.description)
 
     def token_is_expired(self):
         # type: () -> bool
@@ -102,15 +102,19 @@ def create_authorization_url(self, **kwargs):
         )
         return uri, state, code_verifier
 
-    def request_token(self, authorization_response, code_verifier):
-        # type: (Text, Text) -> None
-        """Do request for a token."""
+    def request_token(self, **kwargs):
+        # type: (Any) -> None
+        """Do request for a token.
+        The *code_verifier* kwarg is required in any cases.
+        Other kwargs can be a combination of either:
+            1. *authorization_response* or;
+            2. *code* and *state*.
+        """
         token = self._request(
             self._client.fetch_token,
             self._token_endpoint,
             grant_type=self.GRANT_AUTHORIZATION_CODE,
-            authorization_response=authorization_response,
-            code_verifier=code_verifier,
+            **kwargs
         )
         self.set_token(token)
         return token

nuxeo/exceptions.py

@@ -124,14 +124,14 @@ def __str__(self):
 
 
 class OAuth2Error(HTTPError):
-    """ Exception thown when an OAuth2 error happens. """
+    """ Exception thrown when an OAuth2 error happens. """
 
     status = 400
 
-    def __init__(self, error, description):
-        # type: (Text, Text) -> None
-        self.stacktrace = error
-        self.message = description
+    def __init__(self, error):
+        # type: (Text) -> None
+        self.message = error
+        self.stacktrace = None
 
 
 class OngoingRequestError(Conflict):

tests/test_exception.py

@@ -52,11 +52,11 @@ def test_crafted_httperror_parse():
 
 
 def test_crafted_oauth2_error():
-    exc = OAuth2Error("invalid_grant", "Cannot refresh token")
+    exc = OAuth2Error("Cannot refresh token")
     assert str(exc)
     assert exc.status == 400
     assert exc.message == "Cannot refresh token"
-    assert exc.stacktrace == "invalid_grant"
+    assert not exc.stacktrace
 
 
 def test_crafted_ongoing_request_error():