def _start_updating(self):
# Start the ProxyUpdater
self._proxy_task = PeriodicTask(self._update_period, self._try_update)
register_shutdown_handler(self._proxy_task.stop)
self._proxy_task.start()
# Start the proxy metrics publisher task.
self._proxy_metrics_task = PeriodicTask(self._update_period,
self._publish_proxy_metrics)
self._proxy_metrics_task.start()
register_shutdown_handler(self._proxy_metrics_task.stop)
def _start_updating(self):
# Start the ProxyUpdater
self._proxy_task = PeriodicTask(self._update_period, self._try_update)
register_shutdown_handler(self._proxy_task.stop)
self._proxy_task.start()
# Start the proxy metrics publisher task.
self._proxy_metrics_task = PeriodicTask(self._update_period,
self._publish_proxy_metrics)
self._proxy_metrics_task.start()
register_shutdown_handler(self._proxy_metrics_task.stop)
class ThreadFlushEngine(FlushEngine):
"""Class that uses a thread to periodically flush.
"""
def __init__(self, period, flush_fn):
super(ThreadFlushEngine, self).__init__(period, flush_fn)
self._thread = PeriodicTask(self._period, self._flush_fn)
def start(self):
"""Override of base method.
"""
self._thread.start()
def stop(self):
"""Override of base method.
"""
self._thread.stop()
def __init__(self, period, flush_fn): super(ThreadFlushEngine, self).__init__(period, flush_fn) self._thread = PeriodicTask(self._period, self._flush_fn)
class ProxyUpdater(object):
def __init__(self, backend, config, update_period, max_update_frequency):
self._backend = ProxyBackendProvider.get_backend(backend,
config,
self._on_update)
self._update_period = int(update_period)
self._max_update_frequency = int(max_update_frequency)
self._needs_update = True
self._last_updated = datetime(1970, 1, 1)
self._updating = False
def _on_update(self):
self._needs_update = True
def _publish_proxy_metrics(self):
"""Publishes proxy metrics if appropriate.
"""
if self._backend.metrics_publisher:
self._backend.metrics_publisher.publish()
def _should_update(self, as_of):
# Needs an update, isn't already updating, and hasn't updated too recently
time_since_last = as_of - self._last_updated
return self._needs_update \
and not self._updating \
and not time_since_last < timedelta(seconds=self._max_update_frequency)
@property
def blueprints(self):
"""
Flask blueprints describing managed APIs.
"""
return self._backend.blueprints
def set_up(self):
self._start_discovery(weight_adjustment_start=None)
self._update(restart_proxy=False)
def start(self, weight_adjustment_delay_seconds):
now = datetime.now()
delay = timedelta(seconds=weight_adjustment_delay_seconds)
weight_adjustment_start = now + delay
self._start_discovery(weight_adjustment_start)
self._start_updating()
def _start_updating(self):
# Start the ProxyUpdater
self._proxy_task = PeriodicTask(self._update_period, self._try_update)
register_shutdown_handler(self._proxy_task.stop)
self._proxy_task.start()
# Start the proxy metrics publisher task.
self._proxy_metrics_task = PeriodicTask(self._update_period,
self._publish_proxy_metrics)
self._proxy_metrics_task.start()
register_shutdown_handler(self._proxy_metrics_task.stop)
def _start_discovery(self, weight_adjustment_start):
self._backend.start_discovery(weight_adjustment_start)
def _try_update(self, as_of=None):
try:
increment_counter(_METRIC_UPDATE_ATTEMPTED)
METRIC_UPDATE_ATTEMPTED.inc()
if not as_of:
as_of = datetime.now()
do_update = self._should_update(as_of)
if do_update:
self._needs_update = False
self._updating= True
try:
self._update(restart_proxy=True)
except Exception as e:
increment_counter(_METRIC_UPDATE_ATTEMPT_FAILED)
METRIC_UPDATE_ATTEMPT_FAILED.labels(type=e.args[0]).inc()
logger.exception('Failed to update configuration.')
finally:
self._updating = False
except Exception as e:
increment_counter(_METRIC_UPDATE_ATTEMPT_FAILED)
METRIC_UPDATE_ATTEMPT_FAILED.labels(type=e.args[0]).inc()
logger.exception('Error updating.')
def _update(self, restart_proxy=True):
self._backend.update(restart_proxy)
METRIC_UPDATE_ATTEMPT_SUCCEEDED.inc()
class ProxyUpdater(object):
def __init__(self, backend, config, update_period, max_update_frequency):
self._backend = ProxyBackendProvider.get_backend(backend,
config,
self._on_update)
self._update_period = int(update_period)
self._max_update_frequency = int(max_update_frequency)
self._needs_update = True
self._last_updated = datetime(1970, 1, 1)
self._updating = False
def _on_update(self):
self._needs_update = True
def _publish_proxy_metrics(self):
"""Publishes proxy metrics if appropriate.
"""
if self._backend.metrics_publisher:
self._backend.metrics_publisher.publish()
def _should_update(self, as_of):
# Needs an update, isn't already updating, and hasn't updated too recently
time_since_last = as_of - self._last_updated
return self._needs_update \
and not self._updating \
and not time_since_last < timedelta(seconds=self._max_update_frequency)
@property
def blueprints(self):
"""
Flask blueprints describing managed APIs.
"""
return self._backend.blueprints
def set_up(self):
self._start_discovery(weight_adjustment_start=None)
self._update(restart_proxy=False)
def start(self, weight_adjustment_delay_seconds):
now = datetime.now()
delay = timedelta(seconds=weight_adjustment_delay_seconds)
weight_adjustment_start = now + delay
self._start_discovery(weight_adjustment_start)
self._start_updating()
def _start_updating(self):
# Start the ProxyUpdater
self._proxy_task = PeriodicTask(self._update_period, self._try_update)
register_shutdown_handler(self._proxy_task.stop)
self._proxy_task.start()
# Start the proxy metrics publisher task.
self._proxy_metrics_task = PeriodicTask(self._update_period,
self._publish_proxy_metrics)
self._proxy_metrics_task.start()
register_shutdown_handler(self._proxy_metrics_task.stop)
def _start_discovery(self, weight_adjustment_start):
self._backend.start_discovery(weight_adjustment_start)
def _try_update(self, as_of=None):
try:
increment_counter(_METRIC_UPDATE_ATTEMPTED)
if not as_of:
as_of = datetime.now()
do_update = self._should_update(as_of)
if do_update:
self._needs_update = False
self._updating= True
try:
self._update(restart_proxy=True)
except Exception:
logger.exception('Failed to update configuration.')
finally:
self._updating = False
except Exception:
increment_counter(_METRIC_UPDATE_ATTEMPT_FAILED)
logger.exception('Error updating.')
def _update(self, restart_proxy=True):
self._backend.update(restart_proxy)