added get_response_json function to return json from aioweb

tests/test_get_response_json.py

@@ -0,0 +1,80 @@
+"""unit tests: sessions.get_response_json parses a body or logs and returns None
+
+run from the repo root:
+    uv run pytest tests/test_response_json.py
+
+offline — the aioweb Response is faked at the leaf; nothing is sent.
+"""
+
+import logging
+
+import pytest
+
+from monitor_utils.sessions import get_response_json
+
+
+class FakeResponse:
+    def __init__(self, body):
+        self.body = body
+
+    def json(self):
+        return self.body
+
+
+def warnings(caplog):
+    return [r for r in caplog.records if r.levelno == logging.WARNING]
+
+
+def test_dict_body_is_returned_without_logging(caplog):
+    with caplog.at_level(logging.WARNING, logger="monitor_utils.sessions"):
+        assert get_response_json(FakeResponse({"a": 1})) == {"a": 1}
+    assert warnings(caplog) == []
+
+
+def test_none_body_logs_and_returns_none(caplog):
+    with caplog.at_level(logging.WARNING, logger="monitor_utils.sessions"):
+        assert get_response_json(FakeResponse(None), category="c1", page=2) is None
+    (record,) = warnings(caplog)
+    assert record.message == "unexpected response"
+    assert record.body_type == "NoneType"
+    assert record.body == "None"
+    assert (record.category, record.page) == ("c1", 2)
+
+
+@pytest.mark.parametrize("body", [[1, 2], "text", 42, b"bytes"])
+def test_wrong_shape_logs_type_and_truncated_body(body, caplog):
+    with caplog.at_level(logging.WARNING, logger="monitor_utils.sessions"):
+        assert get_response_json(FakeResponse(body)) is None
+    (record,) = warnings(caplog)
+    assert record.body_type == type(body).__name__
+    assert record.body == str(body)[:200]
+
+
+def test_body_preview_is_capped_at_200_chars(caplog):
+    with caplog.at_level(logging.WARNING, logger="monitor_utils.sessions"):
+        get_response_json(FakeResponse("x" * 1000))
+    (record,) = warnings(caplog)
+    assert len(record.body) == 200
+
+
+def test_expected_accepts_other_types(caplog):
+    with caplog.at_level(logging.WARNING, logger="monitor_utils.sessions"):
+        assert get_response_json(FakeResponse([1]), expected=list) == [1]
+        assert get_response_json(FakeResponse([1]), expected=(dict, list)) == [1]
+        assert get_response_json(FakeResponse({}), expected=list) is None
+    assert len(warnings(caplog)) == 1
+
+
+def test_warning_goes_to_the_passed_logger(caplog):
+    with caplog.at_level(logging.WARNING):
+        get_response_json(
+            FakeResponse(None), logger=logging.getLogger("woot.woot_monitor")
+        )
+    (record,) = warnings(caplog)
+    assert record.name == "woot.woot_monitor"
+
+
+def test_empty_dict_counts_as_a_dict(caplog):
+    with caplog.at_level(logging.WARNING, logger="monitor_utils.sessions"):
+        assert get_response_json(FakeResponse({})) == {}
+    assert warnings(caplog) == []