Issue #751 better error when .well-known/openid-configuration is down

Author: soxofaan

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 
 - `sar_backscatter`: try to retrieve coefficient options from backend ([#693](https://github.com/Open-EO/openeo-python-client/issues/693))
+- Improve error message when OIDC provider is unavailable ([#751](https://github.com/Open-EO/openeo-python-client/issues/751))
 
 ### Changed
 

openeo/rest/auth/oidc.py

@@ -268,9 +268,12 @@ def __init__(
             raise ValueError("At least `issuer` or `discovery_url` should be specified")
         if not requests_session:
             requests_session = requests.Session()
-        discovery_resp = requests_session.get(self.discovery_url, timeout=20)
-        discovery_resp.raise_for_status()
-        self.config = discovery_resp.json()
+        try:
+            discovery_resp = requests_session.get(self.discovery_url, timeout=20)
+            discovery_resp.raise_for_status()
+            self.config = discovery_resp.json()
+        except Exception as e:
+            raise OidcException(f"Failed to obtain OIDC discovery document from {self.discovery_url!r}: {e!r}") from e
         self.issuer = issuer or self.config["issuer"]
         # Minimal set of scopes to request
         self._supported_scopes = self.config.get("scopes_supported", ["openid"])

tests/rest/auth/test_oidc.py

@@ -238,6 +238,15 @@ def test_provider_info_get_scopes_string_refresh_token_offline_access(requests_m
     assert p.get_scopes_string() == "openid"
 
 
+def test_provider_info_issuer_broken_json(requests_mock):
+    requests_mock.get("https://authit.test/.well-known/openid-configuration", text="<marquee>nope!</marquee>")
+    with pytest.raises(
+        OidcException,
+        match="Failed to obtain OIDC discovery document from 'https://authit.test/.well-known/openid-configuration': JSONDecodeError",
+    ):
+        OidcProviderInfo(issuer="https://authit.test")
+
+
 def test_oidc_client_info_uses_device_flow_pkce_support(requests_mock):
     oidc_issuer = "https://oidc.test"
     oidc_mock = OidcMock(