test: follow observation cursors past empty pages (#2099)

The e2e helper get_observations stopped on an empty page, which the
observations v2 API can now return while meta.cursor is set. Two e2e tests
also asserted no cursor for unbounded no-match queries, which depends on
how fast the server scans back to 2020-01-01; bound them to the last day so
the server covers the range in one scan window.

Co-authored-by: Hassieb Pakzad <68423100+hassiebp@users.noreply.github.com>

Author: DavidTraina

tests/e2e/test_core_sdk.py

@@ -1843,15 +1843,23 @@ def test_get_observations():
 
 
 def test_get_observations_for_unknown_trace_is_empty():
-    response = get_api(retry=False).observations.get_many(trace_id=create_uuid())
+    # A lower bound within the server's first 7-day scan window makes one
+    # request cover the whole range, so the cursor is reliably absent.
+    response = get_api(retry=False).observations.get_many(
+        trace_id=create_uuid(),
+        from_start_time=datetime.now(timezone.utc) - timedelta(days=1),
+    )
 
     assert response.data == []
     assert response.meta.cursor is None
 
 
 def test_get_observations_empty():
     # Fetch observations with a filter that should return no results
-    response = get_api(retry=False).observations.get_many(name=create_uuid())
+    response = get_api(retry=False).observations.get_many(
+        name=create_uuid(),
+        from_start_time=datetime.now(timezone.utc) - timedelta(days=1),
+    )
 
     assert response.data == []
     assert response.meta.cursor is None

tests/support/utils.py

@@ -186,7 +186,8 @@ def get_observations(
         )
         observations.extend(response.data)
         cursor = response.meta.cursor
-        if not cursor or not response.data:
+        # Pages can be short or empty before the end.
+        if not cursor:
             break
 
     # The events table can briefly return several rows for one span until

tests/unit/test_e2e_support.py

@@ -124,11 +124,12 @@ def test_user_metadata_drops_server_added_keys():
     assert user_metadata(observation) == {"key": "value"}
 
 
-def test_get_observations_follows_cursor_and_sorts_by_start_time(monkeypatch):
+def test_get_observations_follows_cursor_past_empty_pages_and_sorts(monkeypatch):
     calls = []
     pages = {
-        None: _page([_observation(2), _observation(0)], cursor="next"),
-        "next": _page([_observation(1)]),
+        None: _page([_observation(2), _observation(0)], cursor="empty"),
+        "empty": _page([], cursor="last"),
+        "last": _page([_observation(1)]),
     }
 
     def get_many(**kwargs):
@@ -140,7 +141,7 @@ def get_many(**kwargs):
     observations = get_observations(trace_id="trace-123")
 
     assert [o.id for o in observations] == ["obs-0", "obs-1", "obs-2"]
-    assert [call["cursor"] for call in calls] == [None, "next"]
+    assert [call["cursor"] for call in calls] == [None, "empty", "last"]
     assert all(call["trace_id"] == "trace-123" for call in calls)