def real_doout(dest_path, element):
if dest_path is None:
stdout(element)
stdoutf()
else:
dfile=os.path.join(dest_path, element)
code, msg=touch(dfile)
if code!="ok":
logging.warning("Can't touch file '%s' (%s)" % (dfile, msg))
def do_write_done(src_filename):
dfile = "%s.done" % src_filename
code, _ = touch(dfile)
if code != "ok":
raise Exception("Can't write '.done' file: %s" % dfile)
def run_aws(node_id, proc, polling_interval, queue_name, topic_name, dst_path, delete_queue):
if topic_name is None:
raise Exception("Need a topic_name")
auto_queue = False
if queue_name is None:
auto_queue = True
queue_name = gen_queue_name()
def setup_private_queue():
conn = boto.connect_sqs()
q = conn.create_queue(queue_name)
q.set_message_class(RawMessage)
return (conn, q)
# SETUP PRIVATE QUEUE
logging.info("Creating queue '%s'" % queue_name)
sqs_conn, q = retry(setup_private_queue, logmsg="Having trouble creating queue...")
topic_arn = build_topic_arn(sqs_conn, topic_name)
logging.info("topic_arn: %s" % topic_arn)
### create topic
def create_topic():
"""
{'CreateTopicResponse':
{'ResponseMetadata':
{'RequestId': '5e2c6700-4dd0-11e1-b421-41716ce69b95'},
'CreateTopicResult': {'TopicArn': 'arn:aws:sns:us-east-1:674707187858:election'}}}
"""
snsconn = boto.connect_sns()
snsconn.create_topic(topic_name)
retry(create_topic, logmsg="Having trouble creating topic...")
# SUBSCRIBE TO TOPIC
def sub_topic():
snsconn = boto.connect_sns()
snsconn.subscribe_sqs_queue(topic_arn, q)
return snsconn
snsconn = retry(sub_topic, logmsg="Having trouble subscribing queue to topic...")
logging.info("Subscribed to topic '%s'" % topic_name)
current_state = "NL"
MSGS = {"NL": "Leadership lost", "L": "Leadership gained", "ML": "Leadership momentum"}
poll_count = 0
def cleanup():
rm(dst_path)
if auto_queue or delete_queue:
logging.info("... deleting queue")
try:
sqs_conn.delete_queue(q)
except:
pass
ppid = os.getppid()
logging.info("Process pid: %s" % os.getpid())
logging.info("Parent pid: %s" % ppid)
logging.info("Starting loop...")
while True:
if os.getppid() != ppid:
logging.warning("Parent terminated... exiting")
cleanup()
break
try:
## do a bit of garbage collection :)
global sigtermReceived
if sigtermReceived:
cleanup()
raise SignalTerminate()
#########################################
try:
### BATCH PROCESS - required!!!
while True:
rawmsg = q.read()
if rawmsg is not None:
jsonmsg = json.loads(rawmsg.get_body())
q.delete_message(rawmsg)
## SNS encapsulates the original message...
nodeid = str(jsonmsg["Message"])
transition, current_state = proc.send((poll_count, nodeid))
jstdout({"state": current_state})
if transition:
logging.info(MSGS[current_state])
if current_state == "L":
code, _ = touch(dst_path)
logging.info("Created '%s': %s" % (dst_path, code))
else:
code, _ = rm(dst_path)
logging.info("Deleted '%s': %s" % (dst_path, code))
else:
break
except SQSDecodeError:
logging.warning("Message decoding error")
except Exception, e:
logging.error(str(e))
continue
msg = str(node_id)
logging.debug("Publishing our 'node id': %s" % node_id)
try:
snsconn.publish(topic_arn, msg)
except:
try:
snsconn.publish(topic_arn, msg)
except:
logging.warning("Can't publish to topic '%s'" % topic_name)
logging.debug("... sleeping for %s seconds" % polling_interval)
sleep(polling_interval)
poll_count = poll_count + 1
except KeyboardInterrupt:
cleanup()
raise
