cname_add should have an option to set the ttl

[oyvindhagberg]

The API lets you set a ttl on a cname that is different from the ttl setting on the host object.
But the CLI doesn't let you do that, yet.
Let's add an option to the cname_add command. And consider doing something similar to cname_replace so you can modify the ttl value without deleting the cname and adding it again.

mreg-cli/mreg_cli/host.py

Lines 1292 to 1341 in 9a66b8c

	def cname_add(args):
	"""Add a CNAME record to host.
	"""
	# Get host info or raise exception
	info = host_info_by_name(args.name)
	alias = clean_hostname(args.alias)
	# If alias name already exist as host, abort.
	try:
	host_info_by_name(alias)
	cli_error("The alias name is in use by an existing host. Find a new alias.")
	except HostNotFoundWarning:
	pass
	# Check if cname already in use
	if cname_exists(alias):
	cli_warning("The alias is already in use.")
	# Check if the cname is in a zone controlled by mreg
	check_zone_for_hostname(alias, args.force)
	data = {'host': info['id'],
	'name': alias}
	# Create CNAME record
	path = "/api/v1/cnames/"
	history.record_post(path, "", data, undoable=False)
	post(path, **data)
	cli_info("Added cname alias {} for {}".format(alias, info["name"]),
	print_msg=True)
	# Add 'cname_add' as a sub command to the 'host' command
	host.add_command(
	prog='cname_add',
	description='Add a CNAME record to host. If NAME is an alias '
	'the cname host is used as target for ALIAS.',
	short_desc='Add CNAME.',
	callback=cname_add,
	flags=[
	Flag('name',
	description='Name of target host.',
	metavar='NAME'),
	Flag('alias',
	description='Name of CNAME host.',
	metavar='ALIAS'),
	Flag('-force',
	action='store_true',
	description='Enable force.'),
	],
	)

[terjekv]

#151 suggests that one can use host set_ttl <cname> <ttl> to set the ttl of a cname. The current workflow thus seems to be:

host cname_add arecord cname
host set_ttl cname 400

This should be documented. :)