fix: qr code value (#304)

* fix: qr code value

* Applied suggestions from code review

* feat: universal link

README.SATOSA.md

@@ -77,7 +77,7 @@ To install the OpenID4VP SATOSA backend you just need to:
 
 | Parameter                              | Description                                                                    | Example value                                 |
 | -------------------------------------- | ------------------------------------------------------------------------------ | --------------------------------------------- |
-| config.authorization.url_scheme        | The URL scheme for the authorization                                           | eudiw                                         |
+| config.authorization.url_scheme        | Either a custom URL scheme for the authorization, or a universal link          | haip, https://wallet.example                                       |
 | config.authorization.scopes            | The list of scopes for the authorization                                       | [pid-sd-jwt:unique_id+given_name+family_name] |
 | config.authorization.default_acr_value | The default authentication context class reference value for the authorization | https://www.spid.gov.it/SpidL2                |
 

example/satosa/integration_test/same_device_integration_test.py

@@ -21,8 +21,9 @@
 db_engine_inst = setup_test_db_engine()
 db_engine_inst = apply_trust_settings(db_engine_inst)
 
-def _extract_request_uri(e: requests.exceptions.InvalidSchema) -> str:
-    request_uri = re.search(r'request_uri=(.*?)(?:\'|$)', urllib.parse.unquote_plus(e.args[0])).group(1)
+def _extract_request_uri(e: Exception) -> str:
+    request_uri: str = re.search(r'request_uri=(.*?)(?:\'|\s|$)', urllib.parse.unquote_plus(e.args[0])).group(1)
+    request_uri = request_uri.rstrip()
     return request_uri
 
 
@@ -43,7 +44,11 @@ def _extract_request_uri(e: requests.exceptions.InvalidSchema) -> str:
         timeout=TIMEOUT_S
     )
 except requests.exceptions.InvalidSchema as e:
+    # custom url scheme such as 'haip' or 'eudiw' will raise this exception
     request_uri = _extract_request_uri(e)
+except requests.exceptions.ConnectionError as e:
+    # universal link such as 'https://wallet.example' will raise this exception
+    request_uri = _extract_request_uri(e.args[0])
 
 sign_request_obj = http_user_agent.get(
     request_uri,

pyeudiw/satosa/default/openid4vp_backend.py

@@ -205,20 +205,18 @@ def pre_request_endpoint(self, context: Context, internal_request, **kwargs) ->
             'client_id': self.client_id,
             'request_uri': f"{self.absolute_request_url}?id={state}",
         }
-        url_params = urlencode(payload, quote_via=quote_plus)
+
+        response_url = self._build_authz_request_url(payload)
 
         if is_smartphone(context.http_headers.get('HTTP_USER_AGENT')):
             # Same Device flow
-            res_url = f'{self.config["authorization"]["url_scheme"]}://authorize?{url_params}'
-            return Redirect(res_url)
+            return Redirect(response_url)
 
         # Cross Device flow
-        res_url = f'{self.client_id}?{url_params}'
-
         result = self.template.qrcode_page.render(
             {
                 "qrcode_color": self.config["qrcode"]["color"],
-                "qrcode_text": res_url,
+                "qrcode_text": response_url,
                 "qrcode_size": self.config["qrcode"]["size"],
                 "qrcode_logo_path": self.config["qrcode"]["logo_path"],
                 "qrcode_expiration_time": self.config["qrcode"]["expiration_time"],
@@ -342,6 +340,19 @@ def db_engine(self) -> DBEngine:
 
         return self._db_engine
 
+    def _build_authz_request_url(self, payload: dict) -> str:
+        scheme = self.config["authorization"]["url_scheme"]
+        if "://" not in scheme:
+            scheme = scheme + "://"
+        if not scheme.endswith("/"):
+            scheme = scheme + "/"
+        # NOTE: path component is currently unused by the protocol, but currently
+        # we leave it there as 'authorize' to stress the fact that this is an
+        # OAuth 2.0 request modified by JAR (RFC9101)
+        path = "authorize"
+        query_params = urlencode(payload, quote_via=quote_plus)
+        return f"{scheme}{path}?{query_params}"
+
     @property
     def default_metadata_private_jwk(self) -> tuple:
         """Returns the default metadata private JWK"""