sr_pulse

Sarracenia v02 Pulse Message Format/Protocol

Date: June 2018
Version: 2.18.05b4
Manual section:7
Manual group:MetPX-Sarracenia

SYNOPSIS

AMQP Topic: <version>.pulse.[tick|message]

Body: <message>

DESCRIPTION

Sr_pulse messages are sent out periodically (default is every minute) so that subscribers with very low frequency of subscription matches will well maintain a connection, across firewalls. Consumers can check every heartbeat (10 minutes by default) if they have received any pulses. If no pulse has been received, the consumer can try an operation on the channel to confirm connection with the broker. If no connection is present, then consumers should teardown and re-build the it.

AMQP TOPIC

The topic of a pulse message is prefixed with v02.pulse. The sub-topic is either: tick for an ordinary keep-alive message, or message for an administrator message intended for all subscribers.

THE BODY

The body of the message in a tick is the standard timestamp (as in an sr_post(7) message) Format: YYYYMMDDHHMMSS.*<decimalseconds> (Note: The datestamp is always in UTC timezone.)

In the case of a message with the v02.pulse.message topic. The body is a message to be posted in the logs of all subscribers.

FURTHER READING

https://github.com/MetPX - home page of metpx-sarracenia

http://rabbitmq.net - home page of the AMQP broker used to develop Sarracenia.

SEE ALSO

sr_subscribe(1) - the http-only download client.

sr_post(1) - post announcements of specific files.

sr_post(7) - The format of announcement messages.

sr_report(1) - process report messages.

sr_sarra(8) - Subscribe, Acquire, and ReAdvertise tool.

sr_watch(1) - the directory watching daemon.