fix: add_member posts the canonical /eperson/epersons/ href (review)

Code review caught that add_member built the eperson uri-list body as
`{API}/epersons/{uuid}`, dropping the `/eperson` path segment - the canonical
href (used elsewhere in this file, e.g. get_user_by_email) is
`/eperson/epersons/{uuid}`. The bare path does not resolve, so DSpace rejects
the membership POST with 422 and add_member returns False.

The new test asserted the malformed URI, pinning the bug. Corrected the URI in
add_member and the assertion, and marked the test dtq_only: the fix lands on
dtq while main still emits the old path, so it is deselected on the main leg of
the differential-contract job.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: jr-rk

dspace_rest_client/client.py

@@ -1290,7 +1290,9 @@ def add_member(self, group, eperson):
             return False
 
         url = f'{self.API_ENDPOINT}/eperson/groups/{group.uuid}/epersons'
-        eperson_uri = f'{self.API_ENDPOINT}/epersons/{eperson.uuid}'
+        # canonical eperson href is /eperson/epersons/{uuid}; a bare /epersons/
+        # path does not resolve and DSpace rejects the uri-list with a 422
+        eperson_uri = f'{self.API_ENDPOINT}/eperson/epersons/{eperson.uuid}'
         r = self.api_post_uri(url, params=None, uri_list=eperson_uri)
         if r.status_code == 204:
             return True

tests/test_clarin_write.py

@@ -165,14 +165,20 @@ def _group(self):
     def _user(self):
         return User({"uuid": EPERSON_UUID, "email": "a@b.c"})
 
+    @pytest.mark.dtq_only
     def test_posts_eperson_uri_and_returns_true_on_204(self):
+        """The eperson uri-list body must be the canonical /eperson/epersons/
+        href. dtq_only: the fix (dropping the bare /epersons/ path) lands on
+        dtq; main still emits the malformed URI, so this is deselected on the
+        main leg of the differential-contract job."""
         c = make_client()
         url = f"{API}/eperson/groups/{GROUP_UUID}/epersons"
         with requests_mock.Mocker() as m:
             m.post(url, status_code=204)
             self.assertTrue(c.add_member(self._group(), self._user()))
+            # canonical eperson href - /eperson/epersons/, not a bare /epersons/
             self.assertEqual(m.last_request.text,
-                             f"{API}/epersons/{EPERSON_UUID}")
+                             f"{API}/eperson/epersons/{EPERSON_UUID}")
 
     def test_non_204_returns_false(self):
         c = make_client()