def mark_software_available(software, version):
url = "{master_api}/agents/{agent}/software/".format(
master_api=config.get("master_api"),
agent=config.get("agent_id"))
while True:
try:
response = yield post_direct(url, data={
"software": software,
"version": version})
except Exception as error:
delay = http_retry_delay()
logger.error(
"Failed to post availability of software %s, "
"version %s to master: %r. Will retry in %s "
"seconds.",
software, version, error, delay)
deferred = Deferred()
reactor.callLater(delay, deferred.callback, None)
yield deferred
else:
data = yield treq.content(response)
if response.code == OK:
logger.info("Posted availability of software %s, "
"version %s to master.",
software, version)
break
elif response.code >= INTERNAL_SERVER_ERROR:
delay = http_retry_delay()
logger.warning(
"Could not post availability of software %s, "
"version %s. The master responded with "
"INTERNAL_SERVER_ERROR. Retrying in %s "
"seconds.", software, version, delay)
deferred = Deferred()
reactor.callLater(delay, deferred.callback, None)
yield deferred
else:
logger.error(
"Failed to post availability of software %s, "
"version %s: "
"Unexpected status from server %s. Data: %s",
software, version, response.code, data)
break
if self.testing:
self.operation_deferred.callback(None)
def post_agent_to_master(self):
"""
Runs the POST request to contact the master. Running this method
multiple times should be considered safe but is generally something
that should be avoided.
"""
url = self.agents_endpoint()
data = self.system_data()
try:
response = yield post_direct(url, data=data)
except Exception as failure:
delay = http_retry_delay()
if isinstance(failure, ConnectionRefusedError):
svclog.error(
"Failed to POST agent to master, the connection was "
"refused. Retrying in %s seconds", delay)
else: # pragma: no cover
svclog.error(
"Unhandled error when trying to POST the agent to the "
"master. The error was %s.", failure)
if not self.shutting_down:
svclog.info(
"Retrying failed POST to master in %s seconds.", delay)
yield deferLater(reactor, delay, self.post_agent_to_master)
else:
svclog.warning("Not retrying POST to master, shutting down.")
else:
# Master might be down or have some other internal problems
# that might eventually be fixed. Retry the request.
if response.code >= INTERNAL_SERVER_ERROR:
if not self.shutting_down:
delay = http_retry_delay()
svclog.warning(
"Failed to post to master due to a server side error "
"error %s, retrying in %s seconds",
response.code, delay)
yield deferLater(reactor, delay, self.post_agent_to_master)
else:
svclog.warning(
"Failed to post to master due to a server side error "
"error %s. Not retrying, because the agent is "
"shutting down", response.code)
# Master is up but is rejecting our request because there's
# something wrong with it. Do not retry the request.
elif response.code >= BAD_REQUEST:
text = yield response.text()
svclog.error(
"%s accepted our POST request but responded with code %s "
"which is a client side error. The message the server "
"responded with was %r. Sorry, but we cannot retry this "
"request as it's an issue with the agent's request.",
url, response.code, text)
else:
data = yield treq.json_content(response)
config["agent_id"] = data["id"]
config.master_contacted()
if response.code == OK:
svclog.info(
"POST to %s was successful. Agent %s was updated.",
url, config["agent_id"])
elif response.code == CREATED:
svclog.info(
"POST to %s was successful. A new agent "
"with an id of %s was created.",
url, config["agent_id"])
returnValue(data)
def post_shutdown_to_master(self):
"""
This method is called before the reactor shuts down and lets the
master know that the agent's state is now ``offline``
"""
# We're under the assumption that something's wrong with
# our code if we try to call this method before self.shutting_down
# is set.
assert self.shutting_down
yield self.post_shutdown_lock.acquire()
svclog.info("Informing master of shutdown")
# Because post_shutdown_to_master is blocking and needs to
# stop the reactor from finishing we perform the retry in-line
data = None
tries = 0
num_retry_errors = 0
response = None
timed_out = False
while True:
tries += 1
try:
response = yield post_direct(
self.agent_api(),
data={
"state": AgentState.OFFLINE,
"free_ram": memory.free_ram(),
"current_assignments": config["current_assignments"]})
except (ResponseNeverReceived, RequestTransmissionFailed) as error:
num_retry_errors += 1
if num_retry_errors > config["broken_connection_max_retry"]:
svclog.error(
"Failed to post shutdown to the master, "
"caught try-again errors %s times in a row.",
num_retry_errors)
break
elif self.shutdown_timeout < datetime.utcnow():
svclog.error("While posting shutdown to master, caught "
"%s. Shutdown timeout has been reached, not "
"retrying.",
error.__class__.__name__)
break
else:
svclog.debug("While posting shutdown to master, caught "
"%s. Retrying immediately.",
error.__class__.__name__)
# When we get a hard failure it could be an issue with the
# server, although it's unlikely, so we retry. Only retry
# for a set period of time though since the shutdown as a timeout
except Exception as failure:
if self.shutdown_timeout > datetime.utcnow():
delay = http_retry_delay()
svclog.warning(
"State update failed due to unhandled error: %s. "
"Retrying in %s seconds",
failure, delay)
# Wait for 'pause' to fire, introducing a delay
pause = Deferred()
reactor.callLater(delay, pause.callback, None)
yield pause
else:
timed_out = True
svclog.warning(
"State update failed due to unhandled error: %s. "
"Shutdown timeout reached, not retrying.",
failure)
break
else:
data = yield treq.json_content(response)
if response.code == NOT_FOUND:
svclog.warning(
"Agent %r no longer exists, cannot update state.",
config["agent_id"])
break
elif response.code == OK:
svclog.info(
"Agent %r has POSTed shutdown state change "
"successfully.",
config["agent_id"])
break
elif response.code >= INTERNAL_SERVER_ERROR:
if self.shutdown_timeout > datetime.utcnow():
delay = http_retry_delay()
svclog.warning(
"State update failed due to server error: %s. "
"Retrying in %s seconds.",
data, delay)
# Wait for 'pause' to fire, introducing a delay
pause = Deferred()
reactor.callLater(delay, pause.callback, None)
yield pause
else:
timed_out = True
svclog.warning(
"State update failed due to server error: %s. "
"Shutdown timeout reached, not retrying.",
data)
break
yield self.post_shutdown_lock.release()
extra_data = {
"response": response,
"timed_out": timed_out,
"tries": tries,
"retry_errors": num_retry_errors
}
if isinstance(data, dict):
data.update(extra_data)
else:
data = extra_data
returnValue(data)
def reannounce(self, force=False):
"""
Method which is used to periodically contact the master. This
method is generally called as part of a scheduled task.
"""
# Attempt to acquire the reannounce lock but fail after 70%
# of the total time between reannouncements elapses. This should
# help prevent an accumulation of requests in the event the master
# is having issues.
try:
yield self.reannounce_lock.acquire(
config["agent_master_reannounce"] * .70
)
except utility.LockTimeoutError:
svclog.debug("Timed out while waiting to acquire reannounce_lock")
returnValue(None)
if not self.should_reannounce() and not force:
yield self.reannounce_lock.release()
returnValue(None)
svclog.debug("Announcing %s to master", config["agent_hostname"])
data = None
num_retry_errors = 0
while True: # for retries
try:
response = yield post_direct(
self.agent_api(),
data={
"state": config["state"],
"current_assignments": config.get(
"current_assignments", {} # may not be set yet
),
"free_ram": memory.free_ram(),
"disks": disks.disks(as_dict=True)
}
)
except (ResponseNeverReceived, RequestTransmissionFailed) as error:
num_retry_errors += 1
if num_retry_errors > config["broken_connection_max_retry"]:
svclog.error(
"Failed to announce self to the master, "
"caught try-again type errors %s times in a row.",
num_retry_errors)
break
else:
svclog.debug("While announcing self to master, caught "
"%s. Retrying immediately.",
error.__class__.__name__)
except Exception as error:
if force:
delay = http_retry_delay()
svclog.error(
"Failed to announce self to the master: %s. Will "
"retry in %s seconds.", error, delay)
deferred = Deferred()
reactor.callLater(delay, deferred.callback, None)
yield deferred
else:
# Don't retry because reannounce is called periodically
svclog.error(
"Failed to announce self to the master: %s. This "
"request will not be retried.", error)
break
else:
data = yield treq.json_content(response)
if response.code == OK:
config.master_contacted(announcement=True)
svclog.info("Announced self to the master server.")
break
elif response.code >= INTERNAL_SERVER_ERROR:
if not self.shutting_down:
delay = http_retry_delay()
svclog.warning(
"Could not announce self to the master server, "
"internal server error: %s. Retrying in %s "
"seconds.", data, delay)
deferred = Deferred()
reactor.callLater(delay, deferred.callback, None)
yield deferred
else:
svclog.warning(
"Could not announce to master. Not retrying "
"because of pending shutdown.")
break
elif response.code == NOT_FOUND:
svclog.warning("The master says it does not know about our "
"agent id. Posting as a new agent.")
yield self.post_agent_to_master()
break
# If this is a client problem retrying the request
# is unlikely to fix the issue so we stop here
elif response.code >= BAD_REQUEST:
svclog.error(
"Failed to announce self to the master, bad "
"request: %s. This request will not be retried.",
data)
break
else:
svclog.error(
"Unhandled error when posting self to the "
"master: %s (code: %s). This request will not be "
"retried.", data, response.code)
break
yield self.reannounce_lock.release()
returnValue(data)
def post(self, url, **kwargs):
return post_direct(self.get_url(url), **kwargs)