Add identity checking endpoint

Queries iga for an external id matching ours. If a match is found, the
name of the owner is returend. Otherwise we return null. Uses the new
iga module to fetch the data.

gregsite/settings/base.py

@@ -341,3 +341,9 @@ DEFAULT_IDENTITY_SOURCE = "greg"
 # Toggle to prevent verification of NIN from the sponsor frontend.
 # Introduced to prevent using greg for takeover of existing accounts in IGA.
 DISABLE_NIN_VERIFY = False
+
+# Iga client config used by identity checking view when checking iga
+IGA_CLIENT = {
+    "url": "http://example.com/cerebrum/",
+    "headers": {"X-Gravitee-Api-Key": "<KEY>"},
+}

gregui/api/urls.py

 from django.urls import re_path, path
 from rest_framework.routers import DefaultRouter
-from gregui.api.views.identity import IdentityViewSet
+from gregui.api.views.identity import IdentityCheckView, IdentityViewSet
 
 from gregui.api.views.invitation import (
     CheckInvitationView,
@@ -42,4 +42,5 @@ urlpatterns += [
         name="person-search",
     ),
     path("userinfo/", UserInfoView.as_view(), name="userinfo"),
+    path("identitycheck/<int:id>", IdentityCheckView.as_view(), name="identitycheck"),
 ]

gregui/api/views/identity.py

+from django.conf import settings
 from rest_framework.authentication import SessionAuthentication, BasicAuthentication
 from rest_framework.permissions import IsAuthenticated
 from rest_framework.viewsets import GenericViewSet
 from rest_framework import mixins
-from rest_framework.exceptions import MethodNotAllowed
+from rest_framework.views import APIView
+from rest_framework.response import Response
+from rest_framework import status
+
 from greg.models import Identity
 from greg.permissions import IsSponsor
 from gregui.api.serializers.identity import IdentitySerializer
-from gregui.models import GregUserProfile
+from iga import get_iga_client
 
 
 class IdentityViewSet(
@@ -29,3 +33,21 @@ class IdentityViewSet(
     permission_classes = [IsAuthenticated, IsSponsor]
     serializer_class = IdentitySerializer
     http_method_names = ["get", "patch"]
+
+
+class IdentityCheckView(APIView):
+
+    authentication_classes = [SessionAuthentication, BasicAuthentication]
+    permission_classes = [IsAuthenticated, IsSponsor]
+    client = get_iga_client(settings.INSTANCE_NAME, settings.IGA_CLIENT)
+
+    def get(self, request, *args, **kwargs):
+        try:
+            ident: Identity = Identity.objects.get(pk=kwargs["id"])
+        except Identity.DoesNotExist:
+            return Response(
+                f"Unknown identifier: {kwargs['id']}",
+                status=status.HTTP_404_NOT_FOUND,
+            )
+        match = self.client.extid_search(ident.type, ident.value)
+        return Response({"match": match.dict() if match else match})

gregui/tests/api/views/test_identity.py

@@ -30,3 +30,57 @@ def test_identity_patch(client, log_in, user_sponsor, person_foo):
     ident.refresh_from_db()
     assert ident.verified == Identity.Verified.MANUAL
     assert ident.verified_by == GregUserProfile.objects.get(user=user_sponsor).sponsor
+
+
+@pytest.mark.django_db
+def test_identity_check_nonexisting_fnr(
+    requests_mock, client, log_in, user_sponsor, person_foo
+):
+    """Verify that identitycheck endpoint checks iga when queried"""
+    requests_mock.get(
+        "http://example.com/cerebrum/v1/search/persons/external-ids?id_type=NO_BIRTHNO&external_id=12345612345",
+        json={"external_ids": []},
+    )
+    log_in(user_sponsor)
+    url = reverse("gregui-v1:identitycheck", kwargs={"id": person_foo.fnr.id})
+    response = client.get(url)
+    assert response.json() == {"match": None}
+
+
+@pytest.mark.django_db
+def test_identity_check_existing_fnr(
+    requests_mock, client, log_in, user_sponsor, person_foo
+):
+    """Verify that identitycheck endpoint checks iga when queried"""
+    requests_mock.get(
+        "http://example.com/cerebrum/v1/search/persons/external-ids?id_type=NO_BIRTHNO&external_id=12345612345",
+        json={
+            "external_ids": [
+                {
+                    "person_id": 1,
+                    "source_system": "dfo_sap",
+                    "external_id": "12345612345",
+                    "id_type": "NO_BIRTHNO",
+                }
+            ]
+        },
+    )
+    requests_mock.get(
+        "http://example.com/cerebrum/v1/persons/1",
+        json={
+            "contexts": ["string"],
+            "created_at": "2022-02-17T10:17:31.305Z",
+            "href": "http://example.com/cerebrum/v1/search/persons/1",
+            "names": [
+                {"source_system": "dfo_sap", "variant": "FIRST", "name": "Ola"},
+                {"source_system": "dfo_sap", "variant": "LAST", "name": "Nordmann"},
+            ],
+            "birth_date": "2022-02-17T10:17:31.305Z",
+            "id": 1,
+        },
+    )
+
+    log_in(user_sponsor)
+    url = reverse("gregui-v1:identitycheck", kwargs={"id": person_foo.fnr.id})
+    response = client.get(url)
+    assert response.json() == {"match": {"first": "Ola", "last": "Nordmann"}}