Add generating heartbeat alerts to python SDK about python-alerta-client

[satterly]

This is already possible ... https://github.com/alerta/python-alerta-client/blob/master/alertaclient/commands/cmd_heartbeats.py

python-alerta-client/alertaclient/commands/cmd_heartbeats.py

Lines 44 to 98 in aafeece

	if alert:
	with click.progressbar(heartbeats, label='Alerting {} heartbeats'.format(len(heartbeats))) as bar:
	for b in bar:
	params = dict(filter(lambda a: len(a) == 2, map(lambda a: a.split(':'), b.tags)))
	environment = params.get('environment', 'Production')
	group = params.get('group', 'System')
	tags = list(filter(lambda a: not a.startswith('environment:') and
	not a.startswith('group:'), b.tags))
	if b.status == 'expired': # aka. "stale"
	client.send_alert(
	resource=b.origin,
	event='HeartbeatFail',
	correlate=['HeartbeatFail', 'HeartbeatSlow', 'HeartbeatOK'],
	group=group,
	environment=environment,
	service=['Alerta'],
	severity=severity,
	value='{}'.format(b.since),
	text='Heartbeat not received in {} seconds'.format(b.timeout),
	tags=tags,
	type='heartbeatAlert',
	timeout=timeout,
	customer=b.customer
	)
	elif b.status == 'slow':
	client.send_alert(
	resource=b.origin,
	event='HeartbeatSlow',
	correlate=['HeartbeatFail', 'HeartbeatSlow', 'HeartbeatOK'],
	group=group,
	environment=environment,
	service=['Alerta'],
	severity=severity,
	value='{}ms'.format(b.latency),
	text='Heartbeat took more than {}ms to be processed'.format(MAX_LATENCY),
	tags=tags,
	type='heartbeatAlert',
	timeout=timeout,
	customer=b.customer
	)
	else:
	client.send_alert(
	resource=b.origin,
	event='HeartbeatOK',
	correlate=['HeartbeatFail', 'HeartbeatSlow', 'HeartbeatOK'],
	group=group,
	environment=environment,
	service=['Alerta'],
	severity=default_normal_severity,
	value='',
	text='Heartbeat OK',
	tags=tags,
	type='heartbeatAlert',
	customer=b.customer