Raise PseudonymExchangeError when the crypto service rejects a pseudonym

Author: thomas-samoht

app/errors/mapping.py

@@ -8,6 +8,7 @@
     InvalidModelError,
     NotFoundError,
     PseudonymError,
+    PseudonymExchangeError,
     UnauthorizedError,
 )
 
@@ -32,6 +33,7 @@ class ErrorSpec(BaseModel):
     InvalidModelError: ErrorSpec(severity="error", fhir_code="structure", http_status=400),
     InvalidHeaderPropertyError: ErrorSpec(severity="error", fhir_code="invalid", http_status=401),
     PseudonymError: ErrorSpec(severity="error", fhir_code="invalid", http_status=422),
+    PseudonymExchangeError: ErrorSpec(severity="error", fhir_code="invalid", http_status=400, log=True),
     ValueError: ErrorSpec(severity="error", fhir_code="invalid", http_status=400, log=True),
 }
 

app/services/crypto_service_api_client.py

@@ -5,6 +5,7 @@
 
 from app.config import ConfigCryptoServiceApi
 from app.models.pseudonym import OprfPseudonym, PseudonymResponse
+from app.services.exceptions import PseudonymExchangeError
 from app.services.http import HttpService
 
 logger = logging.getLogger(__name__)
@@ -38,7 +39,7 @@ def exchange(self, pseudonym: OprfPseudonym, label: str, mechanism: str) -> Pseu
             logger.exception("Error during request to Crypto Service API")
             raise ConnectionError("Failed to connect to the Crypto Service API")
         except HTTPError:
-            raise ValueError("Invalid pseudonym or oprf_key")
+            raise PseudonymExchangeError("Invalid pseudonym or oprf_key")
         except (JSONDecodeError, KeyError, ValueError):
             logger.exception("Unexpected response from Crypto Service API")
             raise RuntimeError("Unexpected response from the Crypto Service API")

app/services/exceptions.py

@@ -69,3 +69,7 @@ class PseudonymError(Exception):
     def __init__(self, msg: str | None = None) -> None:
         error_msg = "Error occurred while decoding pseudonym" if msg is None else msg
         super().__init__(error_msg)
+
+
+class PseudonymExchangeError(Exception):
+    pass

tests/errors/test_mapping.py

@@ -10,6 +10,7 @@
     InvalidModelError,
     NotFoundError,
     PseudonymError,
+    PseudonymExchangeError,
     UnauthorizedManagingRequestError,
     UnauthorizedScopeError,
     UnauthorizedUraError,
@@ -34,6 +35,7 @@ def _scope_error() -> UnauthorizedScopeError:
         pytest.param(InvalidHeaderPropertyError("aud", "x"), _spec("invalid", 401), id="invalid-header-property"),
         pytest.param(PseudonymError(), _spec("invalid", 422), id="pseudonym"),
         pytest.param(ValueError("boom"), _spec("invalid", 400, log=True), id="value-error"),
+        pytest.param(PseudonymExchangeError("rejected"), _spec("invalid", 400, log=True), id="pseudonym-exchange"),
         pytest.param(InvalidModelError("bad"), _spec("structure", 400), id="invalid-model-outranks-value-error"),
         pytest.param(_scope_error(), _spec("security", 403), id="unauthorized-scope-via-mro"),
         pytest.param(UnauthorizedManagingRequestError(), _spec("security", 403), id="unauthorized-managing-via-mro"),
@@ -50,6 +52,7 @@ def test_spec_for_resolves_the_expected_spec(exc: Exception, expected: ErrorSpec
     [
         pytest.param(PseudonymError(), False, id="pseudonym"),
         pytest.param(ValueError("boom"), True, id="value-error"),
+        pytest.param(PseudonymExchangeError("rejected"), True, id="pseudonym-exchange"),
         pytest.param(RuntimeError("unexpected"), True, id="unmapped"),
         pytest.param(NotFoundError(), False, id="not-found"),
         pytest.param(_scope_error(), False, id="unauthorized-scope"),

tests/routers/test_localize.py

@@ -9,6 +9,7 @@
 from app.models.auth.context import AuthContext, AuthenticationClaims
 from app.models.auth.data import AuthorizationScope
 from app.models.ura import UraNumber
+from app.services.exceptions import PseudonymExchangeError
 from app.services.key_info import KeyInfoService
 from app.services.referral_service import ReferralService
 from tests.routers.conftest import (
@@ -113,7 +114,9 @@ def test_logs_a_failed_localization_with_the_callers_claims(
         monkeypatch: pytest.MonkeyPatch,
     ) -> None:
         key_info_service.add_one("nvi-label", "AES_CBC")
-        monkeypatch.setattr(crypto_client, "exchange", Mock(side_effect=ValueError("Invalid pseudonym or oprf_key")))
+        monkeypatch.setattr(
+            crypto_client, "exchange", Mock(side_effect=PseudonymExchangeError("Invalid pseudonym or oprf_key"))
+        )
 
         with capture_records() as records:
             response = localize_client.post("/localize", json={"pseudonym": "pseu", "oprf_key": "k"})

tests/routers/test_registrations.py

@@ -7,6 +7,7 @@
 from app.debug.crypto_service_api_client_mock import CryptoServiceApiClientMock
 from app.logging.events import Log
 from app.models.auth.data import AuthorizationScope
+from app.services.exceptions import PseudonymExchangeError
 from app.services.key_info import KeyInfoService
 from app.services.referral_service import ReferralService
 from tests.routers.conftest import (
@@ -91,7 +92,9 @@ def test_logs_a_failed_registration_with_the_callers_claims(
         monkeypatch: pytest.MonkeyPatch,
     ) -> None:
         key_info_service.add_one("nvi-label", mechanism="AES_CBC")
-        monkeypatch.setattr(crypto_client, "exchange", Mock(side_effect=ValueError("Invalid pseudonym or oprf_key")))
+        monkeypatch.setattr(
+            crypto_client, "exchange", Mock(side_effect=PseudonymExchangeError("Invalid pseudonym or oprf_key"))
+        )
 
         with capture_records() as records:
             response = source_client.post("/registrations", json={"pseudonym": "pseu", "oprf_key": "key1"})

tests/services/test_crypto_service_api_client.py

@@ -6,6 +6,7 @@
 
 from app.models.pseudonym import OprfPseudonym, PseudonymResponse
 from app.services.crypto_service_api_client import CryptoServiceApiClient
+from app.services.exceptions import PseudonymExchangeError
 
 PSEUDONYM = OprfPseudonym(pseudonym="jwe", oprf_key="bf")
 
@@ -82,7 +83,7 @@ def test_exchange_raises_on_missing_key(crypto_client: CryptoServiceApiClient, h
 def test_exchange_raises_on_http_error(crypto_client: CryptoServiceApiClient, http_mock: MagicMock) -> None:
     http_mock.do_request.side_effect = HTTPError("500")
 
-    with pytest.raises(ValueError):
+    with pytest.raises(PseudonymExchangeError, match="Invalid pseudonym or oprf_key"):
         crypto_client.exchange(PSEUDONYM, "some-label", "CBC_AES")
 
 

tests/services/test_pseudonym_referral_service.py

@@ -8,7 +8,7 @@
 from app.logging.events import Log
 from app.models.pseudonym import OprfPseudonym, PseudonymResponse
 from app.models.ura import UraNumber
-from app.services.exceptions import InvalidKeyInfoError
+from app.services.exceptions import InvalidKeyInfoError, PseudonymExchangeError
 from app.services.key_info import KeyInfoService
 from app.services.pseudonym_referral_service import PseudonymReferralService
 from app.services.pseudonym_resolver import PseudonymResolver
@@ -28,7 +28,7 @@ def exchange(self, pseudonym: OprfPseudonym, label: str, mechanism: str) -> Pseu
 
 class RejectingCryptoClient(CryptoServiceApiClientMock):
     def exchange(self, pseudonym: OprfPseudonym, label: str, mechanism: str) -> PseudonymResponse:
-        raise ValueError("Invalid pseudonym or oprf_key")
+        raise PseudonymExchangeError("Invalid pseudonym or oprf_key")
 
 
 def logged_fields(caplog: pytest.LogCaptureFixture, event: LogEvent) -> list[dict[str, Any]]:
@@ -72,7 +72,7 @@ def test_register_logs_a_failure_when_the_pseudonym_is_invalid(
     ura_number: UraNumber,
     caplog: pytest.LogCaptureFixture,
 ) -> None:
-    with caplog.at_level(logging.INFO), pytest.raises(ValueError):
+    with caplog.at_level(logging.INFO), pytest.raises(PseudonymExchangeError):
         rejecting_service.register(PSEUDONYM, ura_number, SOURCE)
 
     (fields,) = logged_fields(caplog, Log.REFERRAL_REGISTRATION_FAILED)
@@ -107,7 +107,7 @@ def test_localize_logs_a_failure_when_the_pseudonym_is_invalid(
     rejecting_service: PseudonymReferralService,
     caplog: pytest.LogCaptureFixture,
 ) -> None:
-    with caplog.at_level(logging.INFO), pytest.raises(ValueError):
+    with caplog.at_level(logging.INFO), pytest.raises(PseudonymExchangeError):
         rejecting_service.localize(PSEUDONYM, REQUESTING_URA)
 
     (fields,) = logged_fields(caplog, Log.LOCALIZATION_FAILED)