Only use add method when the value is not ellipsis

CHANGES.md

@@ -10,6 +10,8 @@
 
 ### Fixed
 * Bumped uvicorn version to 0.17 (from >=0.12, <=0.14) to resolve security vulnerability related to websockets dependency version ([#343](https://github.com/stac-utils/stac-fastapi/pull/343))
+* `AttributeError` and/or missing properties when requesting the complete `properties`-field in searches. Added test. ([#339](https://github.com/stac-utils/stac-fastapi/pull/339))
+
 
 ## [2.3.0]
 

stac_fastapi/extensions/stac_fastapi/extensions/core/fields/request.py

@@ -34,7 +34,8 @@ def _get_field_dict(fields: Optional[Set[str]]) -> Dict:
                 if parent not in field_dict:
                     field_dict[parent] = {key}
                 else:
-                    field_dict[parent].add(key)
+                    if field_dict[parent] is not ...:
+                        field_dict[parent].add(key)
             else:
                 field_dict[field] = ...  # type:ignore
         return field_dict

stac_fastapi/sqlalchemy/tests/api/test_api.py

@@ -285,3 +285,23 @@ def test_search_line_string_intersects(
     assert resp.status_code == 200
     resp_json = resp.json()
     assert len(resp_json["features"]) == 1
+
+
+def test_app_fields_extension_return_all_properties(
+    load_test_data, app_client, postgres_transactions
+):
+    item = load_test_data("test_item.json")
+    postgres_transactions.create_item(item, request=MockStarletteRequest)
+
+    resp = app_client.get(
+        "/search", params={"collections": ["test-collection"], "fields": "properties"}
+    )
+    assert resp.status_code == 200
+    resp_json = resp.json()
+    feature = resp_json["features"][0]
+    assert len(feature["properties"]) >= len(item["properties"])
+    for expected_prop, expected_value in item["properties"].items():
+        if expected_prop in ("datetime", "created", "updated"):
+            assert feature["properties"][expected_prop][0:19] == expected_value[0:19]
+        else:
+            assert feature["properties"][expected_prop] == expected_value