mirror of
https://github.com/jointakahe/takahe.git
synced 2024-11-14 19:31:06 +00:00
295 lines
10 KiB
Python
295 lines
10 KiB
Python
import datetime
|
|
import logging
|
|
import os
|
|
import signal
|
|
import time
|
|
import uuid
|
|
from concurrent.futures import Future, ThreadPoolExecutor
|
|
|
|
from django.conf import settings
|
|
from django.db import close_old_connections
|
|
from django.utils import timezone
|
|
|
|
from core import sentry
|
|
from core.models import Config
|
|
from stator.models import StatorModel, Stats
|
|
|
|
|
|
class LoopingTimer:
|
|
"""
|
|
Triggers check() to be true once every `interval`.
|
|
"""
|
|
|
|
next_run: float | None = None
|
|
|
|
def __init__(self, interval: float, trigger_at_start=True):
|
|
self.interval = interval
|
|
self.trigger_at_start = trigger_at_start
|
|
|
|
def check(self) -> bool:
|
|
# See if it's our first time being called
|
|
if self.next_run is None:
|
|
# Set up the next call based on trigger_at_start
|
|
if self.trigger_at_start:
|
|
self.next_run = time.monotonic()
|
|
else:
|
|
self.next_run = time.monotonic() + self.interval
|
|
# See if it's time to run the next call
|
|
if time.monotonic() >= self.next_run:
|
|
self.next_run = time.monotonic() + self.interval
|
|
return True
|
|
return False
|
|
|
|
|
|
class StatorRunner:
|
|
"""
|
|
Runs tasks on models that are looking for state changes.
|
|
Designed to run either indefinitely, or just for a few seconds.
|
|
"""
|
|
|
|
def __init__(
|
|
self,
|
|
models: list[type[StatorModel]],
|
|
concurrency: int = getattr(settings, "STATOR_CONCURRENCY", 30),
|
|
concurrency_per_model: int = getattr(
|
|
settings, "STATOR_CONCURRENCY_PER_MODEL", 15
|
|
),
|
|
liveness_file: str | None = None,
|
|
schedule_interval: int = 60,
|
|
delete_interval: int = 30,
|
|
lock_expiry: int = 300,
|
|
run_for: int = 0,
|
|
):
|
|
self.models = models
|
|
self.runner_id = uuid.uuid4().hex
|
|
self.concurrency = concurrency
|
|
self.concurrency_per_model = concurrency_per_model
|
|
self.liveness_file = liveness_file
|
|
self.schedule_interval = schedule_interval
|
|
self.delete_interval = delete_interval
|
|
self.lock_expiry = lock_expiry
|
|
self.run_for = run_for
|
|
self.minimum_loop_delay = 0.5
|
|
self.maximum_loop_delay = 5
|
|
self.tasks: dict[tuple[str, str], Future] = {}
|
|
# Set up SIGALRM handler
|
|
signal.signal(signal.SIGALRM, self.alarm_handler)
|
|
|
|
def run(self):
|
|
sentry.set_takahe_app("stator")
|
|
self.handled = {}
|
|
self.started = time.monotonic()
|
|
self.executor = ThreadPoolExecutor(max_workers=self.concurrency)
|
|
self.loop_delay = self.minimum_loop_delay
|
|
self.scheduling_timer = LoopingTimer(self.schedule_interval)
|
|
self.deletion_timer = LoopingTimer(self.delete_interval)
|
|
# For the first time period, launch tasks
|
|
logging.info("Running main task loop")
|
|
try:
|
|
with sentry.configure_scope() as scope:
|
|
while True:
|
|
# See if we need to run cleaning
|
|
if self.scheduling_timer.check():
|
|
# Set up the watchdog timer (each time we do this the previous one is cancelled)
|
|
signal.alarm(self.schedule_interval * 2)
|
|
# Write liveness file if configured
|
|
if self.liveness_file:
|
|
with open(self.liveness_file, "w") as fh:
|
|
fh.write(str(int(time.time())))
|
|
# Refresh the config
|
|
self.load_config()
|
|
# Do scheduling (stale lock deletion and stats gathering)
|
|
self.run_scheduling()
|
|
|
|
# Clear the cleaning breadcrumbs/extra for the main part of the loop
|
|
sentry.scope_clear(scope)
|
|
|
|
self.clean_tasks()
|
|
|
|
# See if we need to add deletion tasks
|
|
if self.deletion_timer.check():
|
|
self.add_deletion_tasks()
|
|
|
|
# Fetch and run any new handlers we can fit
|
|
self.add_transition_tasks()
|
|
|
|
# Are we in limited run mode?
|
|
if (
|
|
self.run_for
|
|
and (time.monotonic() - self.started) > self.run_for
|
|
):
|
|
break
|
|
|
|
# Prevent busylooping, but also back off delay if we have
|
|
# no tasks
|
|
if self.tasks:
|
|
self.loop_delay = self.minimum_loop_delay
|
|
else:
|
|
self.loop_delay = min(
|
|
self.loop_delay * 1.5,
|
|
self.maximum_loop_delay,
|
|
)
|
|
time.sleep(self.loop_delay)
|
|
|
|
# Clear the Sentry breadcrumbs and extra for next loop
|
|
sentry.scope_clear(scope)
|
|
except KeyboardInterrupt:
|
|
pass
|
|
|
|
# Wait for tasks to finish
|
|
logging.info("Waiting for tasks to complete")
|
|
self.executor.shutdown()
|
|
|
|
# We're done
|
|
logging.info("Complete")
|
|
|
|
def alarm_handler(self, signum, frame):
|
|
"""
|
|
Called when SIGALRM fires, which means we missed a schedule loop.
|
|
Just exit as we're likely deadlocked.
|
|
"""
|
|
logging.warning("Watchdog timeout exceeded")
|
|
os._exit(2)
|
|
|
|
def load_config(self):
|
|
"""
|
|
Refreshes config from the DB
|
|
"""
|
|
Config.system = Config.load_system()
|
|
|
|
def run_scheduling(self):
|
|
"""
|
|
Deletes stale locks for models, and submits their stats.
|
|
"""
|
|
with sentry.start_transaction(op="task", name="stator.run_scheduling"):
|
|
for model in self.models:
|
|
num = self.handled.get(model._meta.label_lower, 0)
|
|
if num or settings.DEBUG:
|
|
logging.info(
|
|
f"{model._meta.label_lower}: Scheduling ({num} handled)"
|
|
)
|
|
self.submit_stats(model)
|
|
model.transition_clean_locks()
|
|
|
|
def submit_stats(self, model: type[StatorModel]):
|
|
"""
|
|
Pop some statistics into the database from our local info for the given model
|
|
"""
|
|
stats_instance = Stats.get_for_model(model)
|
|
if stats_instance.model_label in self.handled:
|
|
stats_instance.add_handled(self.handled[stats_instance.model_label])
|
|
del self.handled[stats_instance.model_label]
|
|
stats_instance.set_queued(model.transition_ready_count())
|
|
stats_instance.trim_data()
|
|
stats_instance.save()
|
|
|
|
def add_transition_tasks(self, call_inline=False):
|
|
"""
|
|
Adds a transition thread for as many instances as we can, given capacity
|
|
and batch size limits.
|
|
"""
|
|
# Calculate space left for tasks
|
|
space_remaining = self.concurrency - len(self.tasks)
|
|
# Fetch new tasks
|
|
for model in self.models:
|
|
if space_remaining > 0:
|
|
for instance in model.transition_get_with_lock(
|
|
number=min(space_remaining, self.concurrency_per_model),
|
|
lock_expiry=(
|
|
timezone.now() + datetime.timedelta(seconds=self.lock_expiry)
|
|
),
|
|
):
|
|
key = (model._meta.label_lower, instance.pk)
|
|
# Don't run two threads for the same thing
|
|
if key in self.tasks:
|
|
continue
|
|
if call_inline:
|
|
task_transition(instance, in_thread=False)
|
|
else:
|
|
self.tasks[key] = self.executor.submit(
|
|
task_transition, instance
|
|
)
|
|
self.handled[model._meta.label_lower] = (
|
|
self.handled.get(model._meta.label_lower, 0) + 1
|
|
)
|
|
space_remaining -= 1
|
|
|
|
def add_deletion_tasks(self, call_inline=False):
|
|
"""
|
|
Adds a deletion thread for each model
|
|
"""
|
|
# Yes, this potentially goes over the capacity limit - it's fine.
|
|
for model in self.models:
|
|
if model.state_graph.deletion_states:
|
|
if call_inline:
|
|
task_deletion(model, in_thread=False)
|
|
else:
|
|
self.tasks[
|
|
model._meta.label_lower, "__delete__"
|
|
] = self.executor.submit(task_deletion, model)
|
|
|
|
def clean_tasks(self):
|
|
"""
|
|
Removes any tasks that are done and handles exceptions if they
|
|
raised them.
|
|
"""
|
|
for key, task in list(self.tasks.items()):
|
|
if task.done():
|
|
del self.tasks[key]
|
|
try:
|
|
task.result()
|
|
except BaseException as e:
|
|
logging.exception(e)
|
|
|
|
def run_single_cycle(self):
|
|
"""
|
|
Testing entrypoint to advance things just one cycle, and allow errors
|
|
to propagate out.
|
|
"""
|
|
self.add_deletion_tasks(call_inline=True)
|
|
self.add_transition_tasks(call_inline=True)
|
|
|
|
|
|
def task_transition(instance: StatorModel, in_thread: bool = True):
|
|
"""
|
|
Runs one state transition/action.
|
|
"""
|
|
task_name = f"stator.task_transition:{instance._meta.label_lower}#{{id}} from {instance.state}"
|
|
started = time.monotonic()
|
|
with sentry.start_transaction(op="task", name=task_name):
|
|
sentry.set_context(
|
|
"instance",
|
|
{
|
|
"model": instance._meta.label_lower,
|
|
"pk": instance.pk,
|
|
"state": instance.state,
|
|
"state_age": instance.state_age,
|
|
},
|
|
)
|
|
result = instance.transition_attempt()
|
|
duration = time.monotonic() - started
|
|
if result:
|
|
logging.info(
|
|
f"{instance._meta.label_lower}: {instance.pk}: {instance.state} -> {result} ({duration:.2f}s)"
|
|
)
|
|
else:
|
|
logging.info(
|
|
f"{instance._meta.label_lower}: {instance.pk}: {instance.state} unchanged ({duration:.2f}s)"
|
|
)
|
|
if in_thread:
|
|
close_old_connections()
|
|
|
|
|
|
def task_deletion(model: type[StatorModel], in_thread: bool = True):
|
|
"""
|
|
Runs one model deletion set.
|
|
"""
|
|
# Loop, running deletions every second, until there are no more to do
|
|
while True:
|
|
deleted = model.transition_delete_due()
|
|
if not deleted:
|
|
break
|
|
logging.info(f"{model._meta.label_lower}: Deleted {deleted} stale items")
|
|
time.sleep(1)
|
|
if in_thread:
|
|
close_old_connections()
|