handlers: fix for remote api handler when remote is string

Ref: [#1476](inspirehep/inspirehep#1476)
Implemented from [this PR](inveniosoftware#202).

invenio_oauthclient/config.py

@@ -200,7 +200,7 @@ class CustomOAuthRemoteApp(OAuthRemoteApp):
 OAUTHCLIENT_REMOTE_APPS = {}
 """Configuration of remote applications."""
 
-OAUTHCLIENT_SESSION_KEY_PREFIX = 'oauth_token'
+OAUTHCLIENT_SESSION_KEY_PREFIX = "oauth_token"
 """Session key prefix used when storing the access token for a remote app."""
 
 OAUTHCLIENT_STATE_EXPIRES = 300
@@ -209,8 +209,14 @@ class CustomOAuthRemoteApp(OAuthRemoteApp):
 OAUTHCLIENT_STATE_ENABLED = True
 """Internal variable used to disable state validation during tests."""
 
-OAUTHCLIENT_SIGNUP_TEMPLATE = 'invenio_oauthclient/signup.html'
+OAUTHCLIENT_SIGNUP_TEMPLATE = "invenio_oauthclient/signup.html"
 """Template for the signup page."""
 
 OAUTHCLIENT_REST_REMOTE_APPS = {}
 """Configuration of remote rest applications."""
+
+OAUTHCLIENT_REST_DEFAULT_RESPONSE_HANDLER = None
+"""Default REST response handler"""
+
+OAUTHCLIENT_REST_DEFAULT_ERROR_HANDLER = None
+"""Default REST error handler"""

invenio_oauthclient/handlers/rest.py

@@ -30,7 +30,7 @@
     account_setup_received
 from ..utils import create_csrf_disabled_registrationform, \
     create_registrationform, fill_form, oauth_authenticate, oauth_get_user, \
-    oauth_register, rest_oauth_register
+    oauth_register, rest_oauth_register, obj_or_import_string
 from .utils import get_session_next_url, response_token_setter, token_getter, \
     token_session_key, token_setter
 
@@ -45,18 +45,16 @@ def response_handler_postmessage(remote, url, payload=dict()):
 
 def default_response_handler(remote, url, payload=dict()):
     """Default response handler."""
+    default_handler = current_app.config.get(
+        "OAUTHCLIENT_REST_DEFAULT_RESPONSE_HANDLER"
+    )
+    if default_handler:
+        return obj_or_import_string(default_handler)(remote, url, payload)
     if payload:
         return redirect(
             "{url}?{payload}".format(url=url, payload=urlencode(payload)))
     return redirect(url)
 
-
-def response_handler(remote, url, payload=dict()):
-    """Handle oauthclient rest response."""
-    return current_oauthclient.response_handler[remote.name](
-        url, payload)
-
-
 #
 # Error handling decorators
 #
@@ -67,47 +65,68 @@ def inner(resp, remote, *args, **kwargs):
         # OAuthErrors should not happen, so they are not caught here. Hence
         # they will result in a 500 Internal Server Error which is what we
         # are interested in.
-        remote_app_config = current_app.config['OAUTHCLIENT_REST_REMOTE_APPS'][
-            remote.name]
         try:
+            remote_app_config = current_app.config['OAUTHCLIENT_REST_REMOTE_APPS'][remote.name]
             return f(resp, remote, *args, **kwargs)
         except OAuthClientError as e:
             current_app.logger.warning(e.message, exc_info=True)
-            return oauth2_handle_error(
+            default_oauth_error_handler = (
+                current_app.config["OAUTHCLIENT_REST_DEFAULT_ERROR_HANDLER"]
+                or oauth2_handle_error
+            )
+            return default_oauth_error_handler(
                 e.remote, e.response, e.code, e.uri, e.description
             )
         except OAuthCERNRejectedAccountError as e:
             current_app.logger.warning(e.message, exc_info=True)
             return response_handler(
                 remote,
-                remote_app_config['error_redirect_url'],
-                payload=dict(
-                    message='CERN account not allowed.',
-                    code=400)
-                )
+                remote_app_config["error_redirect_url"],
+                payload=dict(message="CERN account not allowed.", code=400),
+            )
         except OAuthRejectedRequestError:
             return response_handler(
                 remote,
-                remote_app_config['error_redirect_url'],
+                remote_app_config["error_redirect_url"],
                 payload=dict(
-                    message='You rejected the authentication request.',
-                    code=400)
-                )
+                    message="You rejected the authentication request.", code=400
+                ),
+            )
         except AlreadyLinkedError:
-            msg = 'External service is already linked to another account.'
+            msg = "External service is already linked to another account."
             return response_handler(
                 remote,
-                remote_app_config['error_redirect_url'],
-                payload=dict(
-                    message=msg,
-                    code=400)
-                )
+                remote_app_config["error_redirect_url"],
+                payload=dict(message=msg, code=400),
+            )
     return inner
 
+def oauth_response_error_handler(f):
+    """Decorator to handle exceptions."""
+    @wraps(f)
+    def inner(remote, url, payload=None):
+        try:
+            return f(remote, url, payload)
+        except AttributeError as e:
+            current_app.logger.warning(e, exc_info=True)
+            default_oauth_error_handler = (
+                current_app.config["OAUTHCLIENT_REST_DEFAULT_ERROR_HANDLER"]
+                or oauth2_handle_error
+            )
+            return default_oauth_error_handler(remote, None, 500, url, str(e))
+
+    return inner
 
 #
 # Handlers
 #
+
+@oauth_response_error_handler
+def response_handler(remote, url, payload=None, *args, **kwargs):
+    """Handle oauthclient rest response."""
+    return current_oauthclient.response_handler[remote.name](
+        url, payload)
+
 @oauth_error_handler
 def authorized_default_handler(resp, remote, *args, **kwargs):
     """Store access token in session.
@@ -382,16 +401,19 @@ def signup_handler(remote, *args, **kwargs):
         ))
 
 
-def oauth2_handle_error(remote, resp, error_code, error_uri,
-                        error_description):
+def oauth2_handle_error(remote, resp, error_code, error_uri, error_description):
     """Handle errors during exchange of one-time code for an access tokens."""
-    remote_app_config = current_app.config['OAUTHCLIENT_REST_REMOTE_APPS'][
-        remote.name]
-    return response_handler(
+    error_handler = response_handler
+    url = error_uri
+    if not remote or not hasattr(remote, "name"):
+        error_handler = default_response_handler
+    else:
+        remote_app_config = current_app.config["OAUTHCLIENT_REST_REMOTE_APPS"][
+            remote.name
+        ]
+        url = remote_app_config["error_redirect_url"]
+    return error_handler(
         remote,
-        remote_app_config['error_redirect_url'],
-        payload=dict(
-            message="Authorization with remote service failed.",
-            code=400
-        )
+        url,
+        payload=dict(message="Authorization with remote service failed.", code=400),
     )

tests/conftest.py

@@ -139,7 +139,7 @@ def _init_app(app_):
 def _init_app_rest(app_):
     """Init OAuth rest app."""
     FlaskOAuth(app_)
-    InvenioAccountsRest(app_)
+    InvenioAccountsREST(app_)
     InvenioOAuthClientREST(app_)
     app_.register_blueprint(blueprint_client)
     return app_

tests/test_handlers_rest.py

@@ -10,8 +10,9 @@
 
 from __future__ import absolute_import, print_function
 
+import mock
 import pytest
-from flask import current_app, session, url_for
+from flask import session, url_for
 from flask_login import current_user
 from flask_oauthlib.client import OAuth as FlaskOAuth
 from flask_security import login_user, logout_user
@@ -20,11 +21,11 @@
 from werkzeug.routing import BuildError
 
 from invenio_oauthclient import InvenioOAuthClientREST, current_oauthclient
-from invenio_oauthclient.errors import AlreadyLinkedError, OAuthResponseError
+from invenio_oauthclient.errors import AlreadyLinkedError
 from invenio_oauthclient.handlers import token_session_key, token_setter
 from invenio_oauthclient.handlers.rest import authorized_signup_handler, \
-    disconnect_handler, oauth_error_handler, response_handler_postmessage, \
-    signup_handler
+    default_response_handler, disconnect_handler, oauth2_handle_error, \
+    oauth_error_handler, response_handler_postmessage, signup_handler
 from invenio_oauthclient.models import RemoteToken
 from invenio_oauthclient.utils import oauth_authenticate
 from invenio_oauthclient.views.client import blueprint as blueprint_client
@@ -35,7 +36,7 @@
 @pytest.fixture(scope="function")
 def remote(request, app_rest):
     """."""
-    oauth = current_app.extensions['oauthlib.client']
+    oauth = current_oauthclient.oauth
     return oauth.remote_apps[request.param]
 
 
@@ -241,3 +242,26 @@ def test_response_handler_with_postmessage(remote, app_rest, models_fixture):
     assert expected_message in response
     assert expected_status in response
     assert 'window.opener.postMessage' in response
+
+
+@mock.patch('invenio_oauthclient.handlers.rest.default_response_handler')
+def test_error_handler_with_string_in_remote_regresion(
+    default_response_handler_mock,
+    app_rest
+):
+    remote = 'orcid'
+    oauth2_handle_error(remote, None, None, None, None)
+    default_response_handler_mock.assert_called_once()
+
+
+@mock.patch('invenio_oauthclient.handlers.rest.response_handler_postmessage')
+def test_default_response_handler_from_config(response_handler_mock, app_rest):
+    default_handler = 'invenio_oauthclient.handlers.' \
+                      'rest.response_handler_postmessage'
+    with mock.patch.dict(
+        app_rest.config, {
+            "OAUTHCLIENT_REST_DEFAULT_RESPONSE_HANDLER": default_handler
+        }
+    ):
+        default_response_handler(None, None, None)
+    response_handler_mock.assert_called_once()