Allow RedirectUriConfig be specified in OIDCAuthentication constructo…

…r. (#97)

This allows complete freedom to specify the redirect URI structure
in more complex setups, e.g. when using 'SCRIPT_NAME' with gunicorn.
Ref #95.

src/flask_pyoidc/flask_pyoidc.py

@@ -40,25 +40,28 @@ class OIDCAuthentication:
     OIDCAuthentication object for Flask extension.
     """
 
-    def __init__(self, provider_configurations, app=None):
+    def __init__(self, provider_configurations, app=None, redirect_uri_config = None):
         """
         Args:
             provider_configurations (Mapping[str, ProviderConfiguration]):
                 provider configurations by name
             app (flask.app.Flask): optional Flask app
+            redirect_uri_config (RedirectUriConfig): optional redirect URI config to use instead of
+                'OIDC_REDIRECT_URI' config parameter.
         """
         self._provider_configurations = provider_configurations
 
         self.clients = None
         self._logout_view = None
         self._error_view = None
-        self._redirect_uri_config = None
+        self._redirect_uri_config = redirect_uri_config
 
         if app:
             self.init_app(app)
 
     def init_app(self, app):
-        self._redirect_uri_config = RedirectUriConfig(app.config)
+        if not self._redirect_uri_config:
+            self._redirect_uri_config = RedirectUriConfig.from_config(app.config)
 
         # setup redirect_uri as a flask route
         app.add_url_rule('/' + self._redirect_uri_config.endpoint,

src/flask_pyoidc/redirect_uri_config.py

@@ -16,28 +16,48 @@
 
 
 class RedirectUriConfig:
-    def __init__(self, config):
+    def __init__(self, full_uri, endpoint):
+        self.full_uri = full_uri
+        self.endpoint = endpoint
+
+    def __eq__(self, other):
+        return self.full_uri == other.full_uri and self.endpoint == other.endpoint
+
+    def __str__(self):
+        return '(' + self.full_uri + ', ' + self.endpoint + ')'
+
+    def __repr__(self):
+        return str(self)
+
+    @classmethod
+    def from_config(cls, config):
         if 'OIDC_REDIRECT_URI' in config:
-            self._parse_redirect_uri(config['OIDC_REDIRECT_URI'])
-        else:
-            self._parse_legacy_config(config)
+            return cls(*RedirectUriConfig._parse_redirect_uri(config['OIDC_REDIRECT_URI']))
 
-    def _parse_redirect_uri(self, redirect_uri):
+        return cls(*RedirectUriConfig._parse_legacy_config(config))
+
+    @staticmethod
+    def _parse_redirect_uri(redirect_uri):
         parsed = urlparse(redirect_uri)
-        self.full_uri = redirect_uri
-        self.endpoint = parsed.path.lstrip('/')
+        endpoint = parsed.path.lstrip('/')
+        return redirect_uri, endpoint
 
-    def _parse_legacy_config(self, config):
+    @staticmethod
+    def _parse_legacy_config(config):
         redirect_domain = config.get('OIDC_REDIRECT_DOMAIN', config.get('SERVER_NAME'))
         if not redirect_domain:
             raise ValueError("'OIDC_REDIRECT_URI' must be configured.")
 
         scheme = config.get('PREFERRED_URL_SCHEME', 'http')
-        self.endpoint = config.get('OIDC_REDIRECT_ENDPOINT', 'redirect_uri').lstrip('/')
-        self.full_uri = scheme + '://' + redirect_domain + '/'  + self.endpoint
 
         warnings.warn(
             "Please use 'OIDC_REDIRECT_URI' to configure the redirect_uri for flask-pyoidc. 'OIDC_REDIRECT_DOMAIN' and 'OIDC_REDIRECT_ENDPOINT' have been deprecated.",
             DeprecationWarning,
             stacklevel=2
         )
+
+        endpoint = config.get('OIDC_REDIRECT_ENDPOINT', 'redirect_uri').lstrip('/')
+        full_uri = scheme + '://' + redirect_domain + '/' + endpoint
+
+        return full_uri, endpoint
+

tests/test_flask_pyoidc.py

@@ -7,6 +7,7 @@
 import time
 from datetime import datetime
 from flask import Flask
+from flask_pyoidc.redirect_uri_config import RedirectUriConfig
 from http.cookies import SimpleCookie
 from jwkest import jws
 from oic.oic import AuthorizationResponse
@@ -72,6 +73,17 @@ def assert_view_mock(self, callback_mock, result):
         assert callback_mock.called
         assert result == self.CALLBACK_RETURN_VALUE
 
+    def test_explicit_redirect_uri_config_should_be_preferred(self):
+        redirect_uri_config = RedirectUriConfig('https://example.com/abc/redirect_uri', 'redirect_uri')
+        assert OIDCAuthentication({}, self.app, redirect_uri_config)._redirect_uri_config == redirect_uri_config
+
+    def test_explicit_redirect_uri_config_should_be_preserved_after_init_app(self):
+        redirect_uri_config = RedirectUriConfig('https://example.com/abc/redirect_uri', 'redirect_uri')
+        authn = OIDCAuthentication({}, None, redirect_uri_config)
+        assert authn._redirect_uri_config == redirect_uri_config
+        authn.init_app(self.app)
+        assert authn._redirect_uri_config == redirect_uri_config
+
     def test_should_authenticate_if_no_session(self):
         authn = self.init_app()
         view_mock = self.get_view_mock()

tests/test_redirect_uri_config.py

@@ -6,20 +6,20 @@ class TestRedirectUriConfig(object):
     LEGACY_CONFIG = {'SERVER_NAME': 'example.com', 'PREFERRED_URL_SCHEME': 'http'}
 
     def test_legacy_config_defaults(self):
-        config = RedirectUriConfig(self.LEGACY_CONFIG)
+        config = RedirectUriConfig.from_config(self.LEGACY_CONFIG)
         assert config.endpoint == 'redirect_uri'
         assert config.full_uri == 'http://example.com/redirect_uri'
 
     def test_legacy_config_endpoint(self):
-        config = RedirectUriConfig({'OIDC_REDIRECT_ENDPOINT': '/foo', **self.LEGACY_CONFIG})
+        config = RedirectUriConfig.from_config({'OIDC_REDIRECT_ENDPOINT': '/foo', **self.LEGACY_CONFIG})
         assert config.endpoint == 'foo'
 
     def test_legacy_config_domain(self):
         config = {
             'OIDC_REDIRECT_DOMAIN': 'other.example.com:6000',  # should be preferred over SERVER_NAME
             **self.LEGACY_CONFIG
         }
-        redirect_uri_config = RedirectUriConfig(config)
+        redirect_uri_config = RedirectUriConfig.from_config(config)
         assert redirect_uri_config.full_uri == 'http://other.example.com:6000/redirect_uri'
 
     def test_redirect_uri_config(self):
@@ -28,11 +28,11 @@ def test_redirect_uri_config(self):
             'OIDC_REDIRECT_DOMAIN': 'other.example.com:6000',
             **self.LEGACY_CONFIG
         }
-        redirect_uri_config = RedirectUriConfig(config)
+        redirect_uri_config = RedirectUriConfig.from_config(config)
         assert redirect_uri_config.full_uri == 'https://myexample.com:6000/callback'
         assert redirect_uri_config.endpoint == 'callback'
 
     def test_should_raise_if_missing_all_config(self):
         with pytest.raises(ValueError) as exc_info:
-            RedirectUriConfig({})
+            RedirectUriConfig.from_config({})
         assert 'OIDC_REDIRECT_URI' in str(exc_info.value)