async def _heartbeat(self, heartbeat_interval: float) -> bool:
# Return True if zombied or should reconnect, false if time to die forever.
# Prevent immediately zombie-ing.
self._last_heartbeat_ack_received = date.monotonic()
self._logger.debug("starting heartbeat with interval %ss",
heartbeat_interval)
while not self._closing.is_set() and not self._closed.is_set():
if self._last_heartbeat_ack_received <= self._last_heartbeat_sent:
# Gateway is zombie, close and request reconnect.
self._logger.warning(
"connection has not received a HEARTBEAT_ACK for approx %.1fs and is being disconnected, "
"expect a reconnect shortly",
date.monotonic() - self._last_heartbeat_ack_received,
)
return True
self._logger.log(
ux.TRACE, "preparing to send HEARTBEAT [s:%s, interval:%ss]",
self._seq, heartbeat_interval)
await self._send_heartbeat()
try:
await asyncio.wait_for(self._closing.wait(),
timeout=heartbeat_interval)
# We are closing
break
except asyncio.TimeoutError:
# We should continue
continue
self._logger.debug("heartbeat task is finishing now")
return False
async def throttle(self) -> None:
"""Perform the throttling rate limiter logic.
Iterates repeatedly while the queue is not empty, adhering to any
rate limits that occur in the mean time.
!!! note
You should usually not need to invoke this directly, but if you do,
ensure to call it using `asyncio.create_task`, and store the
task immediately in `throttle_task`.
When this coroutine function completes, it will set the
`throttle_task` to `builtins.None`. This means you can check if throttling
is occurring by checking if `throttle_task` is not `builtins.None`.
"""
_LOGGER.debug(
"you are being rate limited on bucket %s, backing off for %ss",
self.name,
self.get_time_until_reset(date.monotonic()),
)
while self.queue:
sleep_for = self.get_time_until_reset(date.monotonic())
await asyncio.sleep(sleep_for)
while self.remaining > 0 and self.queue:
self.drip()
self.queue.pop(0).set_result(None)
self.throttle_task = None
def acquire(self) -> asyncio.Future[typing.Any]:
"""Acquire time on this rate limiter.
Returns
-------
asyncio.Future[typing.Any]
A future that should be immediately awaited. Once the await
completes, you are able to proceed with the operation that is
under this rate limit.
"""
loop = asyncio.get_running_loop()
future = loop.create_future()
# If we are rate limited, delegate invoking this to the throttler and spin it up
# if it hasn't started. Likewise, if the throttle task is still running, we should
# delegate releasing the future to the throttler task so that we still process
# first-come-first-serve
if self.throttle_task is not None or self.is_rate_limited(
date.monotonic()):
self.queue.append(future)
if self.throttle_task is None:
self.throttle_task = loop.create_task(self.throttle())
else:
self.drip()
future.set_result(None)
return future
def update_rate_limits(
self,
compiled_route: routes.CompiledRoute,
bucket_header: str,
remaining_header: int,
limit_header: int,
date_header: datetime.datetime,
reset_at_header: datetime.datetime,
) -> None:
"""Update the rate limits for a bucket using info from a response.
Parameters
----------
compiled_route : hikari.utilities.routes.CompiledRoute
The compiled _route to get the bucket for.
bucket_header : typing.Optional[builtins.str]
The `X-RateLimit-Bucket` header that was provided in the response.
remaining_header : builtins.int
The `X-RateLimit-Remaining` header cast to an `builtins.int`.
limit_header : builtins.int
The `X-RateLimit-Limit`header cast to an `builtins.int`.
date_header : datetime.datetime
The `Date` header value as a `datetime.datetime`.
reset_at_header : datetime.datetime
The `X-RateLimit-Reset` header value as a `datetime.datetime`.
"""
self.routes_to_hashes[compiled_route.route] = bucket_header
real_bucket_hash = compiled_route.create_real_bucket_hash(
bucket_header)
reset_after = (reset_at_header - date_header).total_seconds()
reset_at_monotonic = date.monotonic() + reset_after
if real_bucket_hash in self.real_hashes_to_buckets:
bucket = self.real_hashes_to_buckets[real_bucket_hash]
_LOGGER.debug(
"updating %s with bucket %s [reset-after:%ss, limit:%s, remaining:%s]",
compiled_route,
real_bucket_hash,
reset_after,
limit_header,
remaining_header,
)
else:
bucket = RESTBucket(real_bucket_hash, compiled_route)
self.real_hashes_to_buckets[real_bucket_hash] = bucket
_LOGGER.debug(
"remapping %s with bucket %s [reset-after:%ss, limit:%s, remaining:%s]",
compiled_route,
real_bucket_hash,
reset_after,
limit_header,
remaining_header,
)
bucket.update_rate_limit(remaining_header, limit_header,
reset_at_monotonic)
def do_gc_pass(self, expire_after: float) -> None:
"""Perform a single garbage collection pass.
This will assess any routes stored in the internal mappings of this
object and remove any that are deemed to be inactive or dead in order
to save memory.
If the removed routes are used again in the future, they will be
re-cached automatically.
Parameters
----------
expire_after : builtins.float
Time after which the last `reset_at` was hit for a bucket to\
remove it. Defaults to `reset_at` + 20 seconds. Higher values will
retain unneeded ratelimit info for longer, but may produce more
effective ratelimiting logic as a result.
!!! warning
You generally have no need to invoke this directly. Use
`RESTBucketManager.start` and `RESTBucketManager.close` to control
this instead.
"""
buckets_to_purge = []
now = date.monotonic()
# We have three main states that a bucket can be in:
# 1. active - the bucket is active and is not at risk of deallocation
# 2. survival - the bucket is inactive but is still fresh enough to be kept alive.
# 3. death - the bucket has been inactive for too long.
active = 0
# Discover and purge
bucket_pairs = self.real_hashes_to_buckets.items()
for full_hash, bucket in bucket_pairs:
if bucket.is_empty and bucket.reset_at + expire_after < now:
# If it is still running a throttle and is in memory, it will remain in memory
# but we will not know about it.
buckets_to_purge.append(full_hash)
if bucket.reset_at >= now:
active += 1
dead = len(buckets_to_purge)
total = len(bucket_pairs)
survival = total - active - dead
for full_hash in buckets_to_purge:
self.real_hashes_to_buckets[full_hash].close()
del self.real_hashes_to_buckets[full_hash]
_LOGGER.log(
ux.TRACE,
"purged %s stale buckets, %s remain in survival, %s active", dead,
survival, active)
async def _start_one_shard(
self,
activity: typing.Optional[presences.Activity],
afk: bool,
idle_since: typing.Optional[datetime.datetime],
status: presences.Status,
large_threshold: int,
shard_id: int,
shard_count: int,
url: str,
) -> shard_impl.GatewayShardImpl:
new_shard = shard_impl.GatewayShardImpl(
event_consumer=self._raw_event_consumer,
http_settings=self._http_settings,
initial_activity=activity,
initial_is_afk=afk,
initial_idle_since=idle_since,
initial_status=status,
large_threshold=large_threshold,
intents=self._intents,
proxy_settings=self._proxy_settings,
shard_id=shard_id,
shard_count=shard_count,
token=self._token,
url=url,
)
start = date.monotonic()
await aio.first_completed(new_shard.start(),
self._closing_event.wait())
end = date.monotonic()
if new_shard.is_alive:
_LOGGER.debug("Shard %s started successfully in %.1fms", shard_id,
(end - start) * 1_000)
return new_shard
raise errors.GatewayError(
f"Shard {shard_id} shut down immediately when starting")
async def _poll_events(self) -> typing.Optional[bool]:
payload = await self._ws.receive_json(timeout=5
) # type: ignore[union-attr]
op = payload[_OP] # opcode int
d = payload[
_D] # data/payload. Usually a dict or a bool for INVALID_SESSION
if op == _DISPATCH:
t = payload[_T] # event name str
s = payload[_S] # seq int
self._logger.log(ux.TRACE, "dispatching %s with seq %s", t, s)
self._dispatch(t, s, d)
elif op == _HEARTBEAT:
await self._send_heartbeat_ack()
self._logger.log(ux.TRACE, "sent HEARTBEAT")
elif op == _HEARTBEAT_ACK:
now = date.monotonic()
self._last_heartbeat_ack_received = now
self._heartbeat_latency = now - self._last_heartbeat_sent
self._logger.log(ux.TRACE, "received HEARTBEAT ACK in %.1fms",
self._heartbeat_latency * 1_000)
elif op == _RECONNECT:
# We should be able to resume...
self._logger.info(
"received instruction to reconnect, will resume existing session"
)
return True
elif op == _INVALID_SESSION:
# We can resume if the payload was `true`.
if not d:
self._logger.info(
"received invalid session, will need to start a new session"
)
self._seq = None
self._session_id = None
else:
self._logger.info(
"received invalid session, will resume existing session")
return True
else:
self._logger.log(
ux.TRACE, "unknown opcode %s received, it will be ignored...",
op)
return None
def update_rate_limit(self, remaining: int, limit: int,
reset_at: float) -> None:
"""Amend the rate limit.
Parameters
----------
remaining : builtins.int
The calls remaining in this time window.
limit : builtins.int
The total calls allowed in this time window.
reset_at : builtins.float
The epoch at which to reset the limit.
!!! note
The `reset_at` epoch is expected to be a `date.monotonic_timestamp`
monotonic epoch, rather than a `time.time` date-based epoch.
"""
self.remaining = remaining
self.limit = limit
self.reset_at = reset_at
self.period = max(0.0, self.reset_at - date.monotonic())
async def start(
self,
*,
activity: typing.Optional[presences.Activity] = None,
afk: bool = False,
check_for_updates: bool = True,
idle_since: typing.Optional[datetime.datetime] = None,
ignore_session_start_limit: bool = False,
large_threshold: int = 250,
shard_ids: typing.Optional[typing.Set[int]] = None,
shard_count: typing.Optional[int] = None,
status: presences.Status = presences.Status.ONLINE,
) -> None:
"""Start the bot, wait for all shards to become ready, and then return.
Other Parameters
----------------
activity : typing.Optional[hikari.presences.Activity]
The initial activity to display in the bot user presence, or
`builtins.None` (default) to not show any.
afk : builtins.bool
The initial AFK state to display in the bot user presence, or
`builtins.False` (default) to not show any.
check_for_updates : builtins.bool
Defaults to `builtins.True`. If `builtins.True`, will check for
newer versions of `hikari` on PyPI and notify if available.
idle_since : typing.Optional[datetime.datetime]
The `datetime.datetime` the user should be marked as being idle
since, or `builtins.None` (default) to not show this.
ignore_session_start_limit : builtins.bool
Defaults to `builtins.False`. If `builtins.False`, then attempting
to start more sessions than you are allowed in a 24 hour window
will throw a `hikari.errors.GatewayError` rather than going ahead
and hitting the IDENTIFY limit, which may result in your token
being reset. Setting to `builtins.True` disables this behavior.
large_threshold : builtins.int
Threshold for members in a guild before it is treated as being
"large" and no longer sending member details in the `GUILD CREATE`
event. Defaults to `250`.
shard_ids : typing.Optional[typing.Set[builtins.int]]
The shard IDs to create shards for. If not `builtins.None`, then
a non-`None` `shard_count` must ALSO be provided. Defaults to
`builtins.None`, which means the Discord-recommended count is used
for your application instead.
shard_count : typing.Optional[builtins.int]
The number of shards to use in the entire distributed application.
Defaults to `builtins.None` which results in the count being
determined dynamically on startup.
status : hikari.presences.Status
The initial status to show for the user presence on startup.
Defaults to `hikari.presences.Status.ONLINE`.
"""
if shard_ids is not None and shard_count is None:
raise TypeError(
"Must pass shard_count if specifying shard_ids manually")
# Dispatch the update checker, the sharding requirements checker, and dispatch
# the starting event together to save a little time on startup.
start_time = date.monotonic()
if check_for_updates:
asyncio.create_task(
ux.check_for_updates(self._http_settings,
self._proxy_settings),
name="check for package updates",
)
requirements_task = asyncio.create_task(
self._rest.fetch_gateway_bot(),
name="fetch gateway sharding settings")
await self.dispatch(lifetime_events.StartingEvent(app=self))
requirements = await requirements_task
if shard_count is None:
shard_count = requirements.shard_count
if shard_ids is None:
shard_ids = set(range(shard_count))
if requirements.session_start_limit.remaining < len(
shard_ids) and not ignore_session_start_limit:
_LOGGER.critical(
"would have started %s session%s, but you only have %s session%s remaining until %s. Starting more "
"sessions than you are allowed to start may result in your token being reset. To skip this message, "
"use bot.run(..., ignore_session_start_limit=True) or bot.start(..., ignore_session_start_limit=True)",
len(shard_ids),
"s" if len(shard_ids) != 1 else "",
requirements.session_start_limit.remaining,
"s" if requirements.session_start_limit.remaining != 1 else "",
requirements.session_start_limit.reset_at,
)
raise errors.GatewayError(
"Attempted to start more sessions than were allowed in the given time-window"
)
_LOGGER.info(
"planning to start %s session%s... you can start %s session%s before the next window starts at %s",
len(shard_ids),
"s" if len(shard_ids) != 1 else "",
requirements.session_start_limit.remaining,
"s" if requirements.session_start_limit.remaining != 1 else "",
requirements.session_start_limit.reset_at,
)
for window_start in range(
0, shard_count,
requirements.session_start_limit.max_concurrency):
window = [
candidate_shard_id for candidate_shard_id in range(
window_start, window_start +
requirements.session_start_limit.max_concurrency)
if candidate_shard_id in shard_ids
]
if not window:
continue
if self._shards:
close_waiter = asyncio.create_task(self._closing_event.wait())
shard_joiners = [
asyncio.ensure_future(s.join())
for s in self._shards.values()
]
try:
# Attempt to wait for all started shards, for 5 seconds, along with the close
# waiter.
# If the close flag is set (i.e. user invoked bot.close), or one or more shards
# die in this time, we shut down immediately.
# If we time out, the joining tasks get discarded and we spin up the next
# block of shards, if applicable.
_LOGGER.info(
"the next startup window is in 5 seconds, please wait..."
)
await aio.first_completed(
aio.all_of(*shard_joiners, timeout=5), close_waiter)
if not close_waiter.cancelled():
_LOGGER.info(
"requested to shut down during startup of shards")
else:
_LOGGER.critical(
"one or more shards shut down unexpectedly during bot startup"
)
return
except asyncio.TimeoutError:
# If any shards stopped silently, we should close.
if any(not s.is_alive for s in self._shards.values()):
_LOGGER.info(
"one of the shards has been manually shut down (no error), will now shut down"
)
return
# new window starts.
except Exception as ex:
_LOGGER.critical(
"an exception occurred in one of the started shards during bot startup: %r",
ex)
raise
started_shards = await aio.all_of(
*(self._start_one_shard(
activity=activity,
afk=afk,
idle_since=idle_since,
status=status,
large_threshold=large_threshold,
shard_id=candidate_shard_id,
shard_count=shard_count,
url=requirements.url,
) for candidate_shard_id in window
if candidate_shard_id in shard_ids))
for started_shard in started_shards:
self._shards[started_shard.id] = started_shard
await self.dispatch(lifetime_events.StartedEvent(app=self))
_LOGGER.info("application started successfully in approx %.0f seconds",
date.monotonic() - start_time)
async def _send_heartbeat(self) -> None:
await self._ws.send_json({
_OP: _HEARTBEAT,
_D: self._seq
}) # type: ignore[union-attr]
self._last_heartbeat_sent = date.monotonic()
async def _run_once(self) -> bool:
self._handshake_completed.clear()
dispatch_disconnect = False
exit_stack = contextlib.AsyncExitStack()
self._ws = await exit_stack.enter_async_context(
_V6GatewayTransport.connect(
http_settings=self._http_settings,
log_filterer=_log_filterer(self._token),
logger=self._logger,
proxy_settings=self._proxy_settings,
url=self._url,
))
try:
# Dispatch CONNECTED synthetic event.
self._event_consumer(self, "CONNECTED", {})
dispatch_disconnect = True
heartbeat_task = await self._wait_for_hello()
try:
if self._seq is not None:
self._logger.debug("resuming session %s", self._session_id)
await self._resume()
else:
self._logger.debug("identifying with new session")
await self._identify()
if self._closing.is_set():
self._logger.debug(
"closing flag was set during handshake, disconnecting with GOING AWAY "
"(_run_once => do not reconnect)")
await self._ws.send_close( # type: ignore[union-attr]
code=errors.ShardCloseCode.GOING_AWAY,
message=b"shard disconnecting")
return False
# Event polling.
while not self._closing.is_set() and not heartbeat_task.done(
) and not heartbeat_task.cancelled():
try:
result = await self._poll_events()
if result is not None:
return result
except asyncio.TimeoutError:
# We should check if the shard is still alive and then poll again after.
pass
# If the heartbeat died due to an error, it should be raised here.
# This will currently allow us to try to resume if that happens
# We return True if zombied.
if await heartbeat_task:
now = date.monotonic()
self._logger.error(
"connection is a zombie, last heartbeat sent %.2fs ago",
now - self._last_heartbeat_sent,
)
self._logger.debug(
"will attempt to reconnect (_run_once => reconnect)")
return True
self._logger.debug(
"shard has requested graceful termination, so will not attempt to reconnect "
"(_run_once => do not reconnect)")
await self._ws.send_close( # type: ignore[union-attr]
code=errors.ShardCloseCode.GOING_AWAY,
message=b"shard disconnecting",
)
return False
finally:
heartbeat_task.cancel()
finally:
ws = self._ws
self._ws = None
await exit_stack.aclose()
if dispatch_disconnect:
# If we managed to connect, we must always send the DISCONNECT event
# afterwards.
self._event_consumer(self, "DISCONNECTED", {})
# Check if we made the socket close or handled it. If we didn't, we should always try to
# reconnect, as aiohttp is probably closing it internally without telling us properly.
if not ws.sent_close: # type: ignore[union-attr]
return True
async def _run(self) -> None:
self._closed.clear()
self._closing.clear()
last_started_at = -float("inf")
backoff = rate_limits.ExponentialBackOff(
base=_BACKOFF_BASE,
maximum=_BACKOFF_CAP,
initial_increment=_BACKOFF_INCREMENT_START,
)
try:
while not self._closing.is_set() and not self._closed.is_set():
if date.monotonic() - last_started_at < _BACKOFF_WINDOW:
time = next(backoff)
self._logger.info("backing off reconnecting for %.2fs",
time)
try:
await asyncio.wait_for(self._closing.wait(),
timeout=time)
# We were told to close.
return
except asyncio.TimeoutError:
# We are going to run once.
pass
try:
last_started_at = date.monotonic()
should_restart = await self._run_once()
if not should_restart:
self._logger.info(
"shard has disconnected and shut down normally")
return
except errors.GatewayConnectionError as ex:
self._logger.error(
"failed to communicate with server, reason was: %s. Will retry shortly",
ex.__cause__,
)
except errors.GatewayServerClosedConnectionError as ex:
if not ex.can_reconnect:
raise
self._logger.info(
"server has closed connection, will reconnect if possible [code:%s, reason:%s]",
ex.code,
ex.reason,
)
# We don't want to back off from this. If Discord keep closing the connection, it is their issue.
# If we back off here, we'll find a mass outage will prevent shards from becoming healthy on
# reconnect in large sharded bots for a very long period of time.
backoff.reset()
except errors.GatewayError as ex:
self._logger.error("encountered generic gateway error",
exc_info=ex)
raise
except Exception as ex:
self._logger.error("encountered some unhandled error",
exc_info=ex)
raise
finally:
self._closing.set()
self._closed.set()