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superset2/tests/unit_tests/utils/cache_test.py

277 lines
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Python

# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements. See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership. The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License. You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied. See the License for the
# specific language governing permissions and limitations
# under the License.
# pylint: disable=import-outside-toplevel, unused-argument
from typing import Any
from unittest.mock import MagicMock
from pytest_mock import MockerFixture
def test_memoized_func(mocker: MockerFixture) -> None:
"""
Test the ``memoized_func`` decorator.
"""
from superset.utils.cache import memoized_func
cache = mocker.MagicMock()
decorator = memoized_func("db:{self.id}:schema:{schema}:view_list", cache)
decorated = decorator(lambda self, schema, cache=False: 42)
self = mocker.MagicMock()
self.id = 1
# skip cache
result = decorated(self, "public", cache=False)
assert result == 42
cache.get.assert_not_called()
# check cache, no cached value
cache.get.return_value = None
result = decorated(self, "public", cache=True)
assert result == 42
cache.get.assert_called_with("db:1:schema:public:view_list")
# check cache, cached value
cache.get.return_value = 43
result = decorated(self, "public", cache=True)
assert result == 43
def _make_cache_instance(mocker: MockerFixture) -> MagicMock:
"""A cache instance whose ``.cache`` is not a ``NullCache``."""
cache_instance = mocker.MagicMock()
cache_instance.cache = object()
return cache_instance
def _patch_config(mocker: MockerFixture, **overrides: Any) -> dict[str, Any]:
config = {
"CACHE_DEFAULT_TIMEOUT": 100,
"STATS_LOGGER": mocker.MagicMock(),
"STORE_CACHE_KEYS_IN_METADATA_DB": False,
"DATA_CACHE_MAX_VALUE_SIZE": None,
}
config.update(overrides)
mocker.patch("superset.utils.cache.app.config", config)
return config
def test_set_and_log_cache_under_threshold(mocker: MockerFixture) -> None:
"""A value under DATA_CACHE_MAX_VALUE_SIZE is cached normally."""
from superset.utils.cache import set_and_log_cache
config = _patch_config(mocker, DATA_CACHE_MAX_VALUE_SIZE=10 * 1024 * 1024)
cache_instance = _make_cache_instance(mocker)
set_and_log_cache(cache_instance, "my_key", {"df": "small"})
cache_instance.set.assert_called_once()
config["STATS_LOGGER"].incr.assert_any_call("set_cache_key")
assert (
mocker.call("skip_cache_value_too_large")
not in config["STATS_LOGGER"].incr.mock_calls
)
def test_set_and_log_cache_over_threshold(mocker: MockerFixture) -> None:
"""A value exceeding DATA_CACHE_MAX_VALUE_SIZE is not cached."""
from superset.utils.cache import set_and_log_cache
config = _patch_config(
mocker,
DATA_CACHE_MAX_VALUE_SIZE=10,
STORE_CACHE_KEYS_IN_METADATA_DB=True,
)
cache_instance = _make_cache_instance(mocker)
mock_session = mocker.patch("superset.utils.cache.db.session")
set_and_log_cache(
cache_instance,
"my_key",
{"df": "a value large enough to exceed the tiny threshold"},
datasource_uid="1__table",
)
cache_instance.set.assert_not_called()
config["STATS_LOGGER"].incr.assert_called_once_with("skip_cache_value_too_large")
assert mocker.call("set_cache_key") not in config["STATS_LOGGER"].incr.mock_calls
mock_session.add.assert_not_called()
def test_set_and_log_cache_disabled_no_serialization(mocker: MockerFixture) -> None:
"""When the limit is None (default), no pickling overhead is incurred."""
from superset.utils.cache import set_and_log_cache
_patch_config(mocker, DATA_CACHE_MAX_VALUE_SIZE=None)
cache_instance = _make_cache_instance(mocker)
mock_dumps = mocker.patch("superset.utils.cache.pickle.dumps")
set_and_log_cache(cache_instance, "my_key", {"df": "small"})
cache_instance.set.assert_called_once()
mock_dumps.assert_not_called()
def test_set_and_log_cache_null_cache(mocker: MockerFixture) -> None:
"""A NullCache backend short-circuits before any set."""
from flask_caching.backends import NullCache
from superset.utils.cache import set_and_log_cache
_patch_config(mocker, DATA_CACHE_MAX_VALUE_SIZE=10)
cache_instance = mocker.MagicMock()
cache_instance.cache = NullCache()
set_and_log_cache(cache_instance, "my_key", {"df": "small"})
cache_instance.set.assert_not_called()
def test_set_and_log_cache_disabled_timeout(mocker: MockerFixture) -> None:
"""A timeout of -1 (CACHE_DISABLED_TIMEOUT) short-circuits before any set."""
from superset.utils.cache import set_and_log_cache
_patch_config(mocker)
cache_instance = _make_cache_instance(mocker)
set_and_log_cache(cache_instance, "my_key", {"df": "small"}, cache_timeout=-1)
cache_instance.set.assert_not_called()
def test_set_and_log_cache_equal_threshold(mocker: MockerFixture) -> None:
"""A value whose size EQUALS the threshold is still cached (guard is ``>``)."""
import pickle
from superset.utils.cache import set_and_log_cache
cache_value = {"df": "boundary"}
# Compute the exact serialized size the function will see, including the
# injected ``dttm`` field, so we can set the threshold to that exact value.
dttm = "2021-01-01T00:00:00"
value = {**cache_value, "dttm": dttm}
exact_size = len(pickle.dumps(value, protocol=pickle.HIGHEST_PROTOCOL))
config = _patch_config(mocker, DATA_CACHE_MAX_VALUE_SIZE=exact_size)
cache_instance = _make_cache_instance(mocker)
# Pin the timestamp so the pickled size matches ``exact_size`` deterministically.
mock_datetime = mocker.patch("superset.utils.cache.datetime")
mock_datetime.now.return_value.replace.return_value.isoformat.return_value = dttm
set_and_log_cache(cache_instance, "my_key", cache_value)
cache_instance.set.assert_called_once()
config["STATS_LOGGER"].incr.assert_any_call("set_cache_key")
assert (
mocker.call("skip_cache_value_too_large")
not in config["STATS_LOGGER"].incr.mock_calls
)
def test_set_and_log_cache_over_threshold_no_datasource(mocker: MockerFixture) -> None:
"""Over-threshold with no datasource_uid: skipped, and no metadata-DB write."""
from superset.utils.cache import set_and_log_cache
config = _patch_config(
mocker,
DATA_CACHE_MAX_VALUE_SIZE=10,
STORE_CACHE_KEYS_IN_METADATA_DB=True,
)
cache_instance = _make_cache_instance(mocker)
mock_session = mocker.patch("superset.utils.cache.db.session")
set_and_log_cache(
cache_instance,
"my_key",
{"df": "a value large enough to exceed the tiny threshold"},
)
cache_instance.set.assert_not_called()
config["STATS_LOGGER"].incr.assert_called_once_with("skip_cache_value_too_large")
mock_session.add.assert_not_called()
def test_set_and_log_cache_over_threshold_warns(mocker: MockerFixture) -> None:
"""The over-threshold branch emits a warning naming the key and sizes."""
from superset.utils.cache import set_and_log_cache
_patch_config(mocker, DATA_CACHE_MAX_VALUE_SIZE=10)
cache_instance = _make_cache_instance(mocker)
mock_logger = mocker.patch("superset.utils.cache.logger")
set_and_log_cache(
cache_instance,
"my_key",
{"df": "a value large enough to exceed the tiny threshold"},
)
mock_logger.warning.assert_called_once()
warning_args = mock_logger.warning.call_args.args
assert "exceeds DATA_CACHE_MAX_VALUE_SIZE" in warning_args[0]
assert "my_key" in warning_args
def test_set_and_log_cache_under_threshold_metadata_db(mocker: MockerFixture) -> None:
"""Under-threshold with datasource_uid + metadata-DB storage writes a CacheKey."""
from superset.utils.cache import set_and_log_cache
config = _patch_config(
mocker,
DATA_CACHE_MAX_VALUE_SIZE=10 * 1024 * 1024,
STORE_CACHE_KEYS_IN_METADATA_DB=True,
)
cache_instance = _make_cache_instance(mocker)
mock_session = mocker.patch("superset.utils.cache.db.session")
mock_cache_key = mocker.patch("superset.utils.cache.CacheKey")
set_and_log_cache(
cache_instance,
"my_key",
{"df": "small"},
cache_timeout=42,
datasource_uid="1__table",
)
cache_instance.set.assert_called_once()
config["STATS_LOGGER"].incr.assert_any_call("set_cache_key")
mock_cache_key.assert_called_once_with(
cache_key="my_key",
cache_timeout=42,
datasource_uid="1__table",
)
mock_session.add.assert_called_once_with(mock_cache_key.return_value)
def test_set_and_log_cache_set_failure_logs(mocker: MockerFixture) -> None:
"""A failure inside the try block is caught and logged as 'Could not cache key'."""
from superset.utils.cache import set_and_log_cache
_patch_config(mocker, DATA_CACHE_MAX_VALUE_SIZE=None)
cache_instance = _make_cache_instance(mocker)
boom = RuntimeError("backend down")
cache_instance.set.side_effect = boom
mock_logger = mocker.patch("superset.utils.cache.logger")
# Should not raise despite the backend failure.
set_and_log_cache(cache_instance, "my_key", {"df": "small"})
mock_logger.warning.assert_called_once_with("Could not cache key %s", "my_key")
mock_logger.exception.assert_called_once_with(boom)