def base() -> str:
return get_api_url(get_loaded_settings())
def test_get_loaded_settings():
settings = load_settings(os.path.join(settings_dir, "settings.yaml"))
assert get_loaded_settings() is settings
def run_experiment(experiment: Experiment,
settings: Settings = None) -> Journal:
"""
Run the given `experiment` method step by step, in the following sequence:
steady probe, action, close probe.
Activities can be executed in background when they have the
`"background"` property set to `true`. In that case, the activity is run in
a thread. By the end of runs, those threads block until they are all
complete.
If the experiment has the `"dry"` property set to `False`, the experiment
runs without actually executing the activities.
NOTE: Tricky to make a decision whether we should rollback when exiting
abnormally (Ctrl-C, SIGTERM...). Afterall, there is a chance we actually
cannot afford to rollback properly. Better bailing to a conservative
approach. This means we swallow :exc:`KeyboardInterrupt` and
:exc:`SystemExit` and do not bubble it back up to the caller. We when were
interrupted, we set the `interrupted` flag of the result accordingly to
notify the caller this was indeed not terminated properly.
"""
logger.info("Running experiment: {t}".format(t=experiment["title"]))
dry = experiment.get("dry", False)
if dry:
logger.warning("Dry mode enabled")
started_at = time.time()
settings = settings if settings is not None else get_loaded_settings()
config = load_configuration(experiment.get("configuration", {}))
secrets = load_secrets(experiment.get("secrets", {}), config)
initialize_global_controls(experiment, config, secrets, settings)
initialize_controls(experiment, config, secrets)
activity_pool, rollback_pool = get_background_pools(experiment)
control = Control()
journal = initialize_run_journal(experiment)
try:
try:
control.begin(
"experiment", experiment, experiment, config, secrets)
# this may fail the entire experiment right there if any of the
# probes fail or fall out of their tolerance zone
try:
state = run_steady_state_hypothesis(
experiment, config, secrets, dry=dry)
journal["steady_states"]["before"] = state
if state is not None and not state["steady_state_met"]:
p = state["probes"][-1]
raise ActivityFailed(
"Steady state probe '{p}' is not in the given "
"tolerance so failing this experiment".format(
p=p["activity"]["name"]))
except ActivityFailed as a:
journal["steady_states"]["before"] = state
journal["status"] = "failed"
logger.fatal(str(a))
else:
try:
journal["run"] = apply_activities(
experiment, config, secrets, activity_pool, dry)
except InterruptExecution:
raise
except Exception:
journal["status"] = "aborted"
logger.fatal(
"Experiment ran into an un expected fatal error, "
"aborting now.", exc_info=True)
else:
try:
state = run_steady_state_hypothesis(
experiment, config, secrets, dry=dry)
journal["steady_states"]["after"] = state
if state is not None and not state["steady_state_met"]:
journal["deviated"] = True
p = state["probes"][-1]
raise ActivityFailed(
"Steady state probe '{p}' is not in the given "
"tolerance so failing this experiment".format(
p=p["activity"]["name"]))
except ActivityFailed as a:
journal["status"] = "failed"
logger.fatal(str(a))
except InterruptExecution as i:
journal["status"] = "interrupted"
logger.fatal(str(i))
except (KeyboardInterrupt, SystemExit):
journal["status"] = "interrupted"
logger.warning("Received an exit signal, "
"leaving without applying rollbacks.")
else:
journal["status"] = journal["status"] or "completed"
try:
journal["rollbacks"] = apply_rollbacks(
experiment, config, secrets, rollback_pool, dry)
except InterruptExecution as i:
journal["status"] = "interrupted"
logger.fatal(str(i))
except (KeyboardInterrupt, SystemExit):
journal["status"] = "interrupted"
logger.warning(
"Received an exit signal."
"Terminating now without running the remaining rollbacks.")
journal["end"] = datetime.utcnow().isoformat()
journal["duration"] = time.time() - started_at
has_deviated = journal["deviated"]
status = "deviated" if has_deviated else journal["status"]
logger.info(
"Experiment ended with status: {s}".format(s=status))
if has_deviated:
logger.info(
"The steady-state has deviated, a weakness may have been "
"discovered")
control.with_state(journal)
try:
control.end("experiment", experiment, experiment, config, secrets)
except ChaosException:
logger.debug("Failed to close controls", exc_info=True)
finally:
cleanup_controls(experiment)
cleanup_global_controls()
return journal
def configure(self, experiment: Experiment, settings: Settings) -> None:
self.settings = settings if settings is not None else \
get_loaded_settings()
self.config = load_configuration(experiment.get("configuration", {}))
self.secrets = load_secrets(experiment.get("secrets", {}), self.config)