enh: use dcor_group_list_for_user for listing user collections

CHANGELOG

@@ -38,6 +38,9 @@
    (only up to `limit` users are returned, by default 20)
  - enh: wait between retries of failed S3 upload requests (5 s, doubling
    with each retry) instead of retrying immediately
+ - enh: use the API action `dcor_group_list_for_user` (ckanext-dcor_schemas
+   1.2.0) for listing the collections of a user, with a fallback for
+   older servers (#108)
  - ref: convert `dcoraid.cli` module into a package; the upload task CLI
    now lives in `dcoraid.cli.task_upload_task`
  - ref: use `super()`, PEP 604 optional type hints, and builtin/

dcoraid/dbmodel/db_api.py

@@ -1,16 +1,22 @@
 from __future__ import annotations
 
 from itertools import islice
+import logging
 import sys
 import time
 import urllib.parse
 
 import numpy as np
 
+from ..api.errors import APIBadRequest
+
 from .db_core import DBInterrogator
 from .extract import DBExtract
 
 
+logger = logging.getLogger(__name__)
+
+
 if sys.version_info >= (3, 12):
     from itertools import batched
 else:
@@ -50,13 +56,22 @@ def get_collections_user(self):
         This includes all collections in which the user has any role
         (also "member").
         """
+        user_id = self.api.user_id
+        if user_id is None:
+            return []
+        try:
+            # DCOR servers with ckanext-dcor_schemas >= 1.2.0
+            return self.api.get("dcor_group_list_for_user")
+        except APIBadRequest as e:
+            if "Action name not known" not in str(e):
+                raise
+            logger.info("The server does not support the API action "
+                        "`dcor_group_list_for_user`, falling back to "
+                        "checking the members of all collections.")
         # CKAN's `group_list_authz` only returns the collections that the
         # user may edit, and there is no API call that returns the
         # collections in which the user is a "member". Therefore, we have
         # to check the members of every collection.
-        user_id = self.api.user_id
-        if user_id is None:
-            return []
         collections = []
         for col in self.get_collections():
             members = self.api.get("member_list",

tests/test_dbmodel_api_lists.py

@@ -3,11 +3,12 @@
 
 import pytest
 
+from dcoraid.api.errors import APIBadRequest
 from dcoraid.dbmodel import db_api
 
 
 def make_interrogator(num_circles=60, num_collections=40, user_id="user-1",
-                      member_of=(), max_items=25):
+                      member_of=(), max_items=25, group_list_action=False):
     """Return an APIInterrogator with a mocked CKAN API
 
     Parameters
@@ -20,6 +21,9 @@ def make_interrogator(num_circles=60, num_collections=40, user_id="user-1",
         Collection names in which the user is a member
     max_items: int
         Maximum number of items CKAN returns with `all_fields=True`
+    group_list_action: bool
+        Whether the server supports the `dcor_group_list_for_user` action
+        (ckanext-dcor_schemas >= 1.2.0)
     """
     circles = [{"id": f"oid-{ii:03d}", "name": f"circle-{ii:03d}"}
                for ii in range(num_circles)]
@@ -44,6 +48,12 @@ def get(api_call, **kwargs):
                 return [["other-user", "user", "admin"]]
         elif api_call == "organization_list_for_user":
             return circles[:2]
+        elif api_call == "dcor_group_list_for_user":
+            if group_list_action:
+                return [c for c in collections if c["name"] in member_of]
+            else:
+                raise APIBadRequest("Bad request - Action name not known: "
+                                    "dcor_group_list_for_user")
         raise ValueError(f"Unexpected API call {api_call}")
 
     api = mock.MagicMock()
@@ -99,10 +109,36 @@ def test_get_circles_user():
 
 def test_get_collections_user():
     """Collections in which the user has any role (also "member")"""
-    ai, _ = make_interrogator(num_collections=40,
-                              member_of=["collection-003", "collection-030"])
+    ai, calls = make_interrogator(num_collections=40,
+                                  member_of=["collection-003",
+                                             "collection-030"],
+                                  group_list_action=True)
+    assert [c["name"] for c in ai.get_collections_user()] == \
+        ["collection-003", "collection-030"]
+    # the server-side action is used (one request)
+    assert [c[0] for c in calls] == ["dcor_group_list_for_user"]
+
+
+def test_get_collections_user_fallback():
+    """Older servers do not support `dcor_group_list_for_user`"""
+    ai, calls = make_interrogator(num_collections=40,
+                                  member_of=["collection-003",
+                                             "collection-030"],
+                                  group_list_action=False)
     assert [c["name"] for c in ai.get_collections_user()] == \
         ["collection-003", "collection-030"]
+    # fall back to checking the members of all collections
+    api_calls = [c[0] for c in calls]
+    assert api_calls[0] == "dcor_group_list_for_user"
+    assert api_calls.count("member_list") == 40
+
+
+def test_get_collections_user_other_bad_request():
+    """Only fall back if the action is not known to the server"""
+    ai, _ = make_interrogator()
+    ai.api.get.side_effect = APIBadRequest("Bad request - something else")
+    with pytest.raises(APIBadRequest, match="something else"):
+        ai.get_collections_user()
 
 
 def test_get_lists_user_anonymous():