synapse-old/tests/test_metrics.py

201 lines
6.6 KiB
Python

# Copyright 2018 New Vector Ltd
# Copyright 2019 Matrix.org Foundation C.I.C.
#
# Licensed 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.
try:
from importlib import metadata
except ImportError:
import importlib_metadata as metadata # type: ignore[no-redef]
from unittest.mock import patch
from pkg_resources import parse_version
from synapse.app._base import _set_prometheus_client_use_created_metrics
from synapse.metrics import REGISTRY, InFlightGauge, generate_latest
from synapse.util.caches.deferred_cache import DeferredCache
from tests import unittest
def get_sample_labels_value(sample):
"""Extract the labels and values of a sample.
prometheus_client 0.5 changed the sample type to a named tuple with more
members than the plain tuple had in 0.4 and earlier. This function can
extract the labels and value from the sample for both sample types.
Args:
sample: The sample to get the labels and value from.
Returns:
A tuple of (labels, value) from the sample.
"""
# If the sample has a labels and value attribute, use those.
if hasattr(sample, "labels") and hasattr(sample, "value"):
return sample.labels, sample.value
# Otherwise fall back to treating it as a plain 3 tuple.
else:
_, labels, value = sample
return labels, value
class TestMauLimit(unittest.TestCase):
def test_basic(self):
gauge = InFlightGauge(
"test1", "", labels=["test_label"], sub_metrics=["foo", "bar"]
)
def handle1(metrics):
metrics.foo += 2
metrics.bar = max(metrics.bar, 5)
def handle2(metrics):
metrics.foo += 3
metrics.bar = max(metrics.bar, 7)
gauge.register(("key1",), handle1)
self.assert_dict(
{
"test1_total": {("key1",): 1},
"test1_foo": {("key1",): 2},
"test1_bar": {("key1",): 5},
},
self.get_metrics_from_gauge(gauge),
)
gauge.unregister(("key1",), handle1)
self.assert_dict(
{
"test1_total": {("key1",): 0},
"test1_foo": {("key1",): 0},
"test1_bar": {("key1",): 0},
},
self.get_metrics_from_gauge(gauge),
)
gauge.register(("key1",), handle1)
gauge.register(("key2",), handle2)
self.assert_dict(
{
"test1_total": {("key1",): 1, ("key2",): 1},
"test1_foo": {("key1",): 2, ("key2",): 3},
"test1_bar": {("key1",): 5, ("key2",): 7},
},
self.get_metrics_from_gauge(gauge),
)
gauge.unregister(("key2",), handle2)
gauge.register(("key1",), handle2)
self.assert_dict(
{
"test1_total": {("key1",): 2, ("key2",): 0},
"test1_foo": {("key1",): 5, ("key2",): 0},
"test1_bar": {("key1",): 7, ("key2",): 0},
},
self.get_metrics_from_gauge(gauge),
)
def get_metrics_from_gauge(self, gauge):
results = {}
for r in gauge.collect():
results[r.name] = {
tuple(labels[x] for x in gauge.labels): value
for labels, value in map(get_sample_labels_value, r.samples)
}
return results
class BuildInfoTests(unittest.TestCase):
def test_get_build(self):
"""
The synapse_build_info metric reports the OS version, Python version,
and Synapse version.
"""
items = list(
filter(
lambda x: b"synapse_build_info{" in x,
generate_latest(REGISTRY).split(b"\n"),
)
)
self.assertEqual(len(items), 1)
self.assertTrue(b"osversion=" in items[0])
self.assertTrue(b"pythonversion=" in items[0])
self.assertTrue(b"version=" in items[0])
class CacheMetricsTests(unittest.HomeserverTestCase):
def test_cache_metric(self):
"""
Caches produce metrics reflecting their state when scraped.
"""
CACHE_NAME = "cache_metrics_test_fgjkbdfg"
cache = DeferredCache(CACHE_NAME, max_entries=777)
items = {
x.split(b"{")[0].decode("ascii"): x.split(b" ")[1].decode("ascii")
for x in filter(
lambda x: b"cache_metrics_test_fgjkbdfg" in x,
generate_latest(REGISTRY).split(b"\n"),
)
}
self.assertEqual(items["synapse_util_caches_cache_size"], "0.0")
self.assertEqual(items["synapse_util_caches_cache_max_size"], "777.0")
cache.prefill("1", "hi")
items = {
x.split(b"{")[0].decode("ascii"): x.split(b" ")[1].decode("ascii")
for x in filter(
lambda x: b"cache_metrics_test_fgjkbdfg" in x,
generate_latest(REGISTRY).split(b"\n"),
)
}
self.assertEqual(items["synapse_util_caches_cache_size"], "1.0")
self.assertEqual(items["synapse_util_caches_cache_max_size"], "777.0")
class PrometheusMetricsHackTestCase(unittest.HomeserverTestCase):
if parse_version(metadata.version("prometheus_client")) < parse_version("0.14.0"):
skip = "prometheus-client too old"
def test_created_metrics_disabled(self) -> None:
"""
Tests that a brittle hack, to disable `_created` metrics, works.
This involves poking at the internals of prometheus-client.
It's not the end of the world if this doesn't work.
This test gives us a way to notice if prometheus-client changes
their internals.
"""
import prometheus_client.metrics
PRIVATE_FLAG_NAME = "_use_created"
# By default, the pesky `_created` metrics are enabled.
# Check this assumption is still valid.
self.assertTrue(getattr(prometheus_client.metrics, PRIVATE_FLAG_NAME))
with patch("prometheus_client.metrics") as mock:
setattr(mock, PRIVATE_FLAG_NAME, True)
_set_prometheus_client_use_created_metrics(False)
self.assertFalse(getattr(mock, PRIVATE_FLAG_NAME, False))