@spec describe_parameters(
  server_node_name :: String.t(),
  parameter_names :: [String.t()],
  client_node_name :: String.t(),
  opts :: keyword()
) :: {:ok, [struct()]} | {:error, term()}

Describe parameter_names on the remote node. If parameter_names is empty, all parameters are described.

Returns {:ok, [%ParameterDescriptor{}]} on success.

@spec get_parameter_types(
  server_node_name :: String.t(),
  parameter_names :: [String.t()],
  client_node_name :: String.t(),
  opts :: keyword()
) :: {:ok, [non_neg_integer()]} | {:error, term()}

Get the parameter types of parameter_names on the remote node.

Returns {:ok, [integer]} on success, where each integer matches the ROS 2 ParameterType constants (e.g. parameter_integer).

@spec get_parameters(
  server_node_name :: String.t(),
  parameter_names :: [String.t()],
  client_node_name :: String.t(),
  opts :: keyword()
) :: {:ok, [{String.t(), term()}]} | {:error, term()}

Get the values of parameter_names from the remote node.

Returns {:ok, [{name, value}, ...]} on success, where value is the Elixir-side decoded value (or nil if the parameter is not set on the server). Returns {:error, reason} on failure.

Options

• :namespace (client node namespace, default "/")
• :server_namespace (default "/")
• :timeout (seconds, float; default nil for infinite)

@spec list_parameters(
  server_node_name :: String.t(),
  client_node_name :: String.t(),
  opts :: keyword()
) :: {:ok, %{names: [String.t()], prefixes: [String.t()]}} | {:error, term()}

List parameters on the remote node.

Options

• :prefixes — list of prefix strings to filter by. Defaults to [] (no filtering).
• :depth — recursion depth. Defaults to 0 (unlimited).
• :namespace, :server_namespace, :timeout — as elsewhere.

Returns {:ok, %{names: [...], prefixes: [...]}} on success.

@spec service_available?(
  server_node_name :: String.t(),
  client_node_name :: String.t(),
  opts :: keyword()
) :: boolean() | {:error, :not_found}

Returns true if the remote parameter services are available, false otherwise. Returns {:error, :not_found} if the parameter client has not been started.

By default, the check is performed against get_parameters. All six services are typically registered together by the server, so this is representative.

@spec set_parameters(
  server_node_name :: String.t(),
  parameters :: [{String.t(), term()} | struct()],
  client_node_name :: String.t(),
  opts :: keyword()
) :: {:ok, [struct()]} | {:error, term()}

Set parameters on the remote node, one by one.

parameters is a list of {name, value} tuples or %Rclex.Pkgs.RclInterfaces.Msg.Parameter{} structs. Each set is independently validated server-side.

Returns {:ok, [%SetParametersResult{}]} on success.

@spec set_parameters_atomically(
  server_node_name :: String.t(),
  parameters :: [{String.t(), term()} | struct()],
  client_node_name :: String.t(),
  opts :: keyword()
) :: {:ok, struct()} | {:error, term()}

Set parameters on the remote node atomically: either all set successfully or none change.

Returns {:ok, %SetParametersResult{}} on success.

@spec start(
  server_node_name :: String.t(),
  client_node_name :: String.t(),
  opts :: keyword()
) :: :ok | {:error, term()}

Start the six parameter service clients on the given local node, all pointing at the parameter services of the remote server_node_name (in server_namespace).

Options

• :namespace — namespace of the local (client) node. Defaults to "/".
• :server_namespace — namespace of the remote (server) node. Defaults to "/".
• :qos — service QoS. Defaults to Rclex.QoS.profile_services_default/0.

@spec stop(
  server_node_name :: String.t(),
  client_node_name :: String.t(),
  opts :: keyword()
) :: :ok

Stop all parameter service clients previously started by start/3 for the given server_node_name/client_node_name pair.

Same options as start/3.