def subscriber(node: Node, topic_name: str, message_type: MsgType,
callback: Callable[[MsgType], Any],
qos_profile: QoSProfile) -> Optional[str]:
"""Initialize a node with a single subscription and spin."""
if message_type is None:
topic_names_and_types = get_topic_names_and_types(
node=node, include_hidden_topics=True)
try:
expanded_name = expand_topic_name(topic_name, node.get_name(),
node.get_namespace())
except ValueError as e:
raise RuntimeError(e)
try:
validate_full_topic_name(expanded_name)
except rclpy.exceptions.InvalidTopicNameException as e:
raise RuntimeError(e)
for n, t in topic_names_and_types:
if n == expanded_name:
if len(t) > 1:
raise RuntimeError(
"Cannot echo topic '%s', as it contains more than one type: [%s]"
% (topic_name, ', '.join(t)))
message_type = t[0]
break
else:
raise RuntimeError(
'Could not determine the type for the passed topic')
msg_module = get_message(message_type)
node.create_subscription(msg_module, topic_name, callback, qos_profile)
rclpy.spin(node)
elif p_type == ParameterType.PARAMETER_STRING:
p_value.string_value = value
return p_value
rclpy.init(args=sys.argv)
node = Node("param_cli_setter")
time.sleep(1)
done = False
while not done:
nodes = [((ns + "/") if ns != "/" else "/") + name
for name, ns in node.get_node_names_and_namespaces()]
nodes = [
fqn for fqn in nodes
if "ros2cli" not in fqn and node.get_name() not in fqn
]
if not nodes:
print("No nodes found, trying again", end="\r")
time.sleep(1)
continue
req_node = select_bullet("Select a node to examine parameters", nodes)
list_params_client = node.create_client(ListParameters,
req_node + "/list_parameters")
get_params_client = node.create_client(GetParameters,
req_node + "/get_parameters")
set_params_client = node.create_client(SetParameters,
req_node + "/set_parameters")
time.sleep(0.2)
if not list_params_client.service_is_ready():
print(
