def sync_cli(argv=sys.argv):
parser = argparse.ArgumentParser(description="""Start synchronization daemon
This daemon connects to zookeeper an watches for changes to the database config.
It then notifies it's plugins when the state changes.
A built-in plugin is zgres-apply which writes the config out to
/var/lib/zgres/databases.json whenever there is a change and calls zgres-apply
to run arbitrary executables dropped into /var/lib/zgres/hooks.
This daemon gets run on all machines which need to know the database connection
info, that means appservers and probably database nodes if you use streaming
replication.
""")
config = zgres.config.parse_args(parser, argv, config_file='sync.ini')
# Keep a reference to the App to prevent garbage collection
app = SyncApp(config)
utils.run_asyncio()
sys.exit(0)
def sync_cli(argv=sys.argv):
parser = argparse.ArgumentParser(description="""Start synchronization daemon
This daemon connects to zookeeper an watches for changes to the database config.
It then notifies it's plugins when the state changes.
A built-in plugin is zgres-apply which writes the config out to
/var/lib/zgres/databases.json whenever there is a change and calls zgres-apply
to run arbitrary executables dropped into /var/lib/zgres/hooks.
This daemon gets run on all machines which need to know the database connection
info, that means appservers and probably database nodes if you use streaming
replication.
""")
config = zgres.config.parse_args(parser, argv)
# Keep a reference to the App to prevent garbage collection
app = App(config)
utils.run_asyncio()
sys.exit(0)
def deadman_cli(argv=sys.argv):
parser = argparse.ArgumentParser(description="""Monitors/controls the local postgresql installation.
This daemon will do these things:
- Register the local postgresql instance with Zookeeper by creating a file
named the IP address to connect on.
- Try to become master by creating the file:
master-{cluster_name}
in zookeeper. If we suceed we create the file /tmp/zgres_become_master.
- Shutdown postgres temporarily if we are master and the zookeeper connection is lost.
- Shutdown postgres permanently if master-{cluster_name} already exists and we didn't create it
(split-brain avoidance)
- Monitor the local postgresql installation, if it becomes unavailable,
withdraw our zookeeper registrations.
It does not:
- maintain streaming replication (use zgres-apply hooks for that)
- do remastering (assumed to have happened before we start)
""")
config = zgres.config.parse_args(parser, argv, config_file='deadman.ini')
result = utils.run_asyncio(App.run, config)
sys.exit(result)
