servo/tests/wpt/servowpt.py
Martin Robinson 5e30ce8532 Filter unknown flaky tests when filtering known intermittents
There are two kinds of flaky/intermittent tests in Servo. The
traditional kind is the test that fails on the CI, but has an associated
bug indicating that the test is an intermittent failure. Many of these
tests have completely unstable results, for instance those where an
unpredictable set of subtests fail. It's impossible to generate stable
results for these, so we have traditionally simply discard these
unexpected results.

Another kind of intermittent test is one that will produce an expected
result when rerun (ie will flake). Some of these are also labeled with
bugs, while some are not. In some cases, there is flakiness in some core
Servo functionality that can lead to *any* test flaking, such as a race
condition that can lead to an early screenshot for reftests. When these
kinds of tests do not have associated bugs, they cause the CI to fail.
In this case, it is impossible to label these tests as intermittent
because it can literally be any test.

This change, reruns failed tests in order to detect unlabeled tests in
the second category. Instead of blocking the CI when the second run
leads to expected results, the CI will now pass, but the flake will be
reported to the new flakiness dashboard. This prevents unrelated flakes
from slowing down the merge queue.
2023-02-21 12:10:02 +01:00

368 lines
13 KiB
Python

# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at https://mozilla.org/MPL/2.0/.
import dataclasses
import grouping_formatter
import json
import os
import re
import sys
import urllib.error
import urllib.parse
import urllib.request
import mozlog
import mozlog.formatters
import multiprocessing
from typing import List, NamedTuple, Optional, Union
from grouping_formatter import UnexpectedResult, UnexpectedSubtestResult
SCRIPT_PATH = os.path.abspath(os.path.dirname(__file__))
SERVO_ROOT = os.path.abspath(os.path.join(SCRIPT_PATH, "..", ".."))
WPT_TOOLS_PATH = os.path.join(SCRIPT_PATH, "web-platform-tests", "tools")
CERTS_PATH = os.path.join(WPT_TOOLS_PATH, "certs")
sys.path.insert(0, WPT_TOOLS_PATH)
import localpaths # noqa: F401,E402
import update # noqa: F401,E402
TRACKER_API = "https://build.servo.org/intermittent-tracker"
TRACKER_API_ENV_VAR = "INTERMITTENT_TRACKER_API"
TRACKER_DASHBOARD_SECRET_ENV_VAR = "INTERMITTENT_TRACKER_DASHBOARD_SECRET"
def determine_build_type(kwargs: dict, target_dir: str):
if kwargs["release"]:
return "release"
elif kwargs["debug"]:
return "debug"
elif os.path.exists(os.path.join(target_dir, "debug")):
return "debug"
elif os.path.exists(os.path.join(target_dir, "release")):
return "release"
return "debug"
def set_if_none(args: dict, key: str, value):
if key not in args or args[key] is None:
args[key] = value
def update_args_for_layout_2020(kwargs: dict):
if kwargs.pop("layout_2020"):
kwargs["test_paths"]["/"]["metadata_path"] = os.path.join(
SCRIPT_PATH, "metadata-layout-2020"
)
kwargs["test_paths"]["/_mozilla/"]["metadata_path"] = os.path.join(
SCRIPT_PATH, "mozilla", "meta-layout-2020"
)
kwargs["include_manifest"] = os.path.join(
SCRIPT_PATH, "include-layout-2020.ini"
)
def run_tests(**kwargs):
from wptrunner import wptrunner
from wptrunner import wptcommandline
# By default, Rayon selects the number of worker threads based on the
# available CPU count. This doesn't work very well when running tests on CI,
# since we run so many Servo processes in parallel. The result is a lot of
# extra timeouts. Instead, force Rayon to assume we are running on a 2 CPU
# environment.
os.environ["RAYON_RS_NUM_CPUS"] = "2"
os.environ["RUST_BACKTRACE"] = "1"
os.environ["HOST_FILE"] = os.path.join(SERVO_ROOT, "tests", "wpt", "hosts")
set_if_none(kwargs, "product", "servo")
set_if_none(kwargs, "config", os.path.join(SCRIPT_PATH, "config.ini"))
set_if_none(kwargs, "include_manifest", os.path.join(SCRIPT_PATH, "include.ini"))
set_if_none(kwargs, "manifest_update", False)
set_if_none(kwargs, "processes", multiprocessing.cpu_count())
set_if_none(kwargs, "ca_cert_path", os.path.join(CERTS_PATH, "cacert.pem"))
set_if_none(
kwargs, "host_key_path", os.path.join(CERTS_PATH, "web-platform.test.key")
)
set_if_none(
kwargs, "host_cert_path", os.path.join(CERTS_PATH, "web-platform.test.pem")
)
kwargs["user_stylesheets"].append(os.path.join(SERVO_ROOT, "resources", "ahem.css"))
if "CARGO_TARGET_DIR" in os.environ:
target_dir = os.path.join(os.environ["CARGO_TARGET_DIR"])
else:
target_dir = os.path.join(SERVO_ROOT, "target")
default_binary_path = os.path.join(
target_dir, determine_build_type(kwargs, target_dir), "servo"
)
if sys.platform == "win32":
target_dir += ".exe"
set_if_none(kwargs, "binary", default_binary_path)
set_if_none(kwargs, "webdriver_binary", default_binary_path)
if kwargs.pop("rr_chaos"):
kwargs["debugger"] = "rr"
kwargs["debugger_args"] = "record --chaos"
kwargs["repeat_until_unexpected"] = True
# TODO: Delete rr traces from green test runs?
prefs = kwargs.pop("prefs")
if prefs:
kwargs["binary_args"] = ["--pref=" + pref for pref in prefs]
if not kwargs.get("no_default_test_types"):
test_types = {
"servo": ["testharness", "reftest", "wdspec"],
"servodriver": ["testharness", "reftest"],
}
product = kwargs.get("product") or "servo"
kwargs["test_types"] = test_types[product]
filter_intermittents_output = kwargs.pop("filter_intermittents", None)
unexpected_raw_log_output_file = kwargs.pop("log_raw_unexpected", None)
raw_log_outputs = kwargs.get("log_raw", [])
wptcommandline.check_args(kwargs)
update_args_for_layout_2020(kwargs)
mozlog.commandline.log_formatters["servo"] = (
grouping_formatter.ServoFormatter,
"Servo's grouping output formatter",
)
use_mach_logging = False
if len(kwargs["test_list"]) == 1:
file_ext = os.path.splitext(kwargs["test_list"][0])[1].lower()
if file_ext in [".htm", ".html", ".js", ".xhtml", ".xht", ".py"]:
use_mach_logging = True
if use_mach_logging:
logger = wptrunner.setup_logging(kwargs, {"mach": sys.stdout})
else:
logger = wptrunner.setup_logging(kwargs, {"servo": sys.stdout})
handler = grouping_formatter.ServoHandler()
logger.add_handler(handler)
wptrunner.run_tests(**kwargs)
return_value = 0 if not handler.unexpected_results else 1
# Filter intermittents if that was specified on the command-line.
if handler.unexpected_results and filter_intermittents_output:
# Copy the list of unexpected results from the first run, so that we
# can access them after the tests are rerun (which changes
# `handler.unexpected_results`). After rerunning some tests will be
# marked as flaky but otherwise the contents of this original list
# won't change.
unexpected_results = list(handler.unexpected_results)
# This isn't strictly necessary since `handler.suite_start()` clears
# the state, but make sure that we are starting with a fresh handler.
handler.reset_state()
print(80 * "=")
print(f"Rerunning {len(unexpected_results)} tests "
"with unexpected results to detect flaky tests.")
unexpected_results_tests = [result.path for result in unexpected_results]
kwargs["test_list"] = unexpected_results_tests
kwargs["include"] = unexpected_results_tests
kwargs["pause_after_test"] = False
wptrunner.run_tests(**kwargs)
# Use the second run to mark tests from the first run as flaky, but
# discard the results otherwise.
# TODO: It might be a good idea to send the new results to the
# dashboard if they were also unexpected.
stable_tests = [result.path for result in handler.unexpected_results]
for result in unexpected_results:
result.flaky = result.path not in stable_tests
all_filtered = filter_intermittents(unexpected_results,
filter_intermittents_output)
return_value = 0 if all_filtered else 1
# Write the unexpected-only raw log if that was specified on the command-line.
if unexpected_raw_log_output_file:
if not raw_log_outputs:
print("'--log-raw-unexpected' not written without '--log-raw'.")
else:
write_unexpected_only_raw_log(
handler.unexpected_results,
raw_log_outputs[0].name,
unexpected_raw_log_output_file
)
return return_value
def update_tests(**kwargs):
from update import updatecommandline
set_if_none(kwargs, "product", "servo")
set_if_none(kwargs, "config", os.path.join(SCRIPT_PATH, "config.ini"))
kwargs["store_state"] = False
updatecommandline.check_args(kwargs)
logger = update.setup_logging(kwargs, {"mach": sys.stdout})
return_value = update.run_update(logger, **kwargs)
return 1 if return_value is update.exit_unclean else 0
class GithubContextInformation(NamedTuple):
build_url: Optional[str]
pull_url: Optional[str]
branch_name: Optional[str]
class TrackerDashboardFilter():
def __init__(self):
base_url = os.environ.get(TRACKER_API_ENV_VAR, TRACKER_API)
self.headers = {
"Content-Type": "application/json"
}
if TRACKER_DASHBOARD_SECRET_ENV_VAR in os.environ:
self.url = f"{base_url}/dashboard/attempts"
secret = os.environ[TRACKER_DASHBOARD_SECRET_ENV_VAR]
self.headers["Authorization"] = f"Bearer {secret}"
else:
self.url = f"{base_url}/dashboard/query"
@staticmethod
def get_github_context_information() -> GithubContextInformation:
github_context = json.loads(os.environ.get("GITHUB_CONTEXT", "{}"))
if not github_context:
return GithubContextInformation(None, None, None)
repository = github_context['repository']
repo_url = f"https://github.com/{repository}"
run_id = github_context['run_id']
build_url = f"{repo_url}/actions/runs/{run_id})"
commit_title = github_context["event"]["head_commit"]["message"]
match = re.match(r"^Auto merge of #(\d+)", commit_title)
pr_url = f"{repo_url}/pull/{match.group(1)}" if match else None
return GithubContextInformation(
build_url,
pr_url,
github_context["ref_name"]
)
def make_data_from_result(
self,
result: Union[UnexpectedResult, UnexpectedSubtestResult],
) -> dict:
data = {
'path': result.path,
'subtest': None,
'expected': result.expected,
'actual': result.actual,
'time': result.time // 1000,
'message': result.message,
'stack': result.stack,
}
if isinstance(result, UnexpectedSubtestResult):
data["subtest"] = result.subtest
return data
def report_failures(self, unexpected_results: List[UnexpectedResult]):
attempts = []
for result in unexpected_results:
attempts.append(self.make_data_from_result(result))
for subtest_result in result.unexpected_subtest_results:
attempts.append(self.make_data_from_result(subtest_result))
context = self.get_github_context_information()
try:
request = urllib.request.Request(
url=self.url,
method='POST',
data=json.dumps({
'branch': context.branch_name,
'build_url': context.build_url,
'pull_url': context.pull_url,
'attempts': attempts
}).encode('utf-8'),
headers=self.headers)
known_intermittents = dict()
with urllib.request.urlopen(request) as response:
for test in json.load(response)["known"]:
known_intermittents[test["path"]] = \
[issue["number"] for issue in test["issues"]]
except urllib.error.HTTPError as e:
print(e)
print(e.readlines())
raise(e)
for result in unexpected_results:
result.issues = known_intermittents.get(result.path, [])
def filter_intermittents(
unexpected_results: List[UnexpectedResult],
output_path: str
) -> bool:
print(f"Filtering {len(unexpected_results)} "
"unexpected results for known intermittents")
dashboard = TrackerDashboardFilter()
dashboard.report_failures(unexpected_results)
def add_result(output, text, results, filter_func) -> None:
filtered = [str(result) for result in filter(filter_func, results)]
if filtered:
output += [f"{text} ({len(results)}): ", *filtered]
def is_stable_and_unexpected(result):
return not result.flaky and not result.issues
output = []
add_result(output, "Flaky unexpected results", unexpected_results,
lambda result: result.flaky)
add_result(output, "Stable unexpected results that are known-intermittent",
unexpected_results, lambda result: not result.flaky and result.issues)
add_result(output, "Stable unexpected results",
unexpected_results, is_stable_and_unexpected)
print("\n".join(output))
with open(output_path, "w", encoding="utf-8") as file:
json.dump([dataclasses.asdict(result) for result in unexpected_results], file)
return not any([is_stable_and_unexpected(result) for result in unexpected_results])
def write_unexpected_only_raw_log(
unexpected_results: List[UnexpectedResult],
raw_log_file: str,
filtered_raw_log_file: str
):
tests = [result.path for result in unexpected_results]
print(f"Writing unexpected-only raw log to {filtered_raw_log_file}")
with open(filtered_raw_log_file, "w", encoding="utf-8") as output:
with open(raw_log_file) as input:
for line in input.readlines():
data = json.loads(line)
if data["action"] in ["suite_start", "suite_end"] or \
("test" in data and data["test"] in tests):
output.write(line)
def main():
from wptrunner import wptcommandline
parser = wptcommandline.create_parser()
kwargs = vars(parser.parse_args())
return run_tests(**kwargs)
if __name__ == "__main__":
sys.exit(0 if main() else 1)