Class: Rclrb::Node

Inherits:
Object
  • Object
show all
Defined in:
lib/rclrb/node.rb

Overview

The node class is the center piece of RCL, it allows to create subscriptions, publishers timers, and services server and clients.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(name) ⇒ Node

Create a node with the given name,



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# File 'lib/rclrb/node.rb', line 9

def initialize(name)
  @node_handle = CApi::RclNodeT.new()
  @services = []
  @subscriptions = []
  @timers = []
  options = CApi.rcl_node_get_default_options()
  @default_callback_group = MutuallyExclusiveCallbackGroup.new
  CApi.handle_result(CApi.rcl_node_init(@node_handle, name, "", Rclrb.rcl_context(), options))
end

Instance Attribute Details

#default_callback_group ⇒ Object (readonly)

Returns the value of attribute default_callback_group.



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# File 'lib/rclrb/node.rb', line 6

def default_callback_group
  @default_callback_group
end

#services ⇒ Object (readonly)

Returns the value of attribute services.



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# File 'lib/rclrb/node.rb', line 6

def services
  @services
end

#subscriptions ⇒ Object (readonly)

Returns the value of attribute subscriptions.



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# File 'lib/rclrb/node.rb', line 6

def subscriptions
  @subscriptions
end

#timers ⇒ Object (readonly)

Returns the value of attribute timers.



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# File 'lib/rclrb/node.rb', line 6

def timers
  @timers
end

Instance Method Details

#create_client(srv_type, srv_name, qos_profile = QoSProfileServicesDefault) ⇒ Object

Create a new service client. Parameters:

  • srv_type: The service type.

  • srv_name (str): The name of the service.

  • qos_profile (optional QoSProfile): The quality of service profile to apply the service client.

  • callback_group (optional CallbackGroup): The callback group for the service client. If None, then the nodes default callback group is used



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# File 'lib/rclrb/node.rb', line 113

def create_client(srv_type, srv_name, qos_profile=QoSProfileServicesDefault)
  handle = CApi::rcl_get_zero_initialized_client()
  client = Client.new(handle, @node_handle, srv_type, srv_name, qos_profile)
  return client
end

#create_publisher(msg_type, topic, qos_profile, callback_group = nil, event_callbacks = nil) ⇒ Object

Create a new Publisher and return it.

Parameters:

  • msg_type The type of ROS messages the publisher will publish.

  • topic (string) The name of the topic the publisher will publish to.

  • qos_profile (QoSProfile or int) A QoSProfile or a history depth to apply to the publisher. In the case that a history depth is provided, the QoS history is set to RMW_QOS_POLICY_HISTORY_KEEP_LAST, the QoS history depth is set to the value of the parameter, and all other QoS settings are set to their default values.

  • callback_group (optional CallbackGroup) The callback group for the publisher’s event handlers. If None, then the node’s default callback group is used.



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# File 'lib/rclrb/node.rb', line 37

def create_publisher(msg_type, topic, qos_profile, callback_group=nil, event_callbacks=nil)
  callback_group = @default_callback_group if callback_group.nil?
  ## * +event_callbacks+ (Optional) – User-defined callbacks for middleware events.
  if event_callbacks != nil
    raise RclError.new("event_callbacks are not supported yet")
  end
  handle = CApi::rcl_get_zero_initialized_publisher()
  publisher = Publisher.new(handle, @node_handle, msg_type, topic, qos_profile, callback_group, event_callbacks)
  return publisher
end

#create_service(srv_type, srv_name, qos_profile = QoSProfileServicesDefault, callback_group = nil, &callback) ⇒ Object

Create a new service server.

Parameters:

  • srv_type: The service type.

  • srv_name (str): The name of the service.

  • callback (block): A user-defined callback function that is called when a service request received by the server, it expects a request and response argument.

  • qos_profile (QoSProfile): The quality of service profile to apply the service server.

  • callback_group (optional CallbackGroup): The callback group for the service server. If None, then the nodes default callback group is used.



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# File 'lib/rclrb/node.rb', line 91

def create_service(srv_type, srv_name, qos_profile=QoSProfileServicesDefault, callback_group=nil, &callback)
  callback_group = @default_callback_group if callback_group.nil?
  handle = CApi::rcl_get_zero_initialized_service()
  service = Service.new(handle, @node_handle, srv_type, srv_name, callback, qos_profile, callback_group)
  @services.append(service)
  return service
end

#create_subscription(msg_type, topic, qos_profile, callback_group = nil, event_callbacks = nil, raw = false, &callback) ⇒ Object

Create a new Subscription and return it. This function will also add the Subscription object to @subscriptions. To unsubscribe it is necesserary to call tje unsubscribe function with the handle to the subscriber.

Parameters:

  • msg_type The type of ROS messages the subscription will subscribe to.

  • topic (string) – The name of the topic the subscription will subscribe to.

  • callback (block) – A user-defined callback function that is called when a message is received by the subscription.

  • qos_profile (QoSProfile or int) – A QoSProfile or a history depth to apply to the subscription. In the case that a history depth is provided, the QoS history is set to RMW_QOS_POLICY_HISTORY_KEEP_LAST, the QoS history depth is set to the value of the parameter, and all other QoS settings are set to their default values.

  • +callback_group (optional CallbackGroup) – The callback group for the subscription. If None, then the nodes default callback group is used.



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# File 'lib/rclrb/node.rb', line 58

def create_subscription(msg_type, topic, qos_profile, callback_group = nil, event_callbacks = nil, raw = false, &callback)
  callback_group = @default_callback_group if callback_group.nil?
  # * +event_callbacks (Optional[SubscriptionEventCallbacks]) – User-defined callbacks for middleware events.
  if event_callbacks != nil
    raise RclError.new("event_callbacks are not supported yet")
  end
  # * +raw (bool) – If True, then received messages will be stored in raw binary representation.
  if raw != false
    raise RclError.new("raw is not supported yet")
  end

  handle = CApi::rcl_get_zero_initialized_subscription()
  subscription = Subscription.new(handle, @node_handle, msg_type, topic, callback, qos_profile, callback_group, event_callbacks, raw)
  @subscriptions.append subscription
  return subscription
end

#create_timer(timer_period_sec, callback_group = nil, clock = Rclrb::RosClock, &callback) ⇒ Object

Create a new timer. The timer will be started and every timer_period_sec number of seconds the provided callback function will be called.

Parameters:

  • timer_period_sec (float): The period (s) of the timer.

  • callback (block): A user-defined callback function that is called when the timer expires.

  • callback_group (optional CallbackGroup): The callback group for the timer. If None, then the nodes default callback group is used.

  • clock (optional Clock): The clock which the timer gets time from.



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# File 'lib/rclrb/node.rb', line 128

def create_timer(timer_period_sec, callback_group=nil, clock=Rclrb::RosClock, &callback)
  callback_group = @default_callback_group if callback_group.nil?
  handle = CApi::rcl_get_zero_initialized_timer()
  timer = Timer.new(handle, @node_handle, timer_period_sec, callback, callback_group, clock)
  @timers.append(timer)
  return timer
end

#get_namespace ⇒ Object

Get the namespace for this node



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# File 'lib/rclrb/node.rb', line 25

def get_namespace
  return CApi.rcl_node_get_namespace @node_handle
end

#remove_service(service) ⇒ Object

Unsubscribe

  • service a service created by create_service



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# File 'lib/rclrb/node.rb', line 102

def remove_service(service)
  @services.remove service
end

#remove_subscription(subscription) ⇒ Object

Unsubscribe

  • subscription a subscription created by create_subscription



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# File 'lib/rclrb/node.rb', line 78

def remove_subscription(subscription)
  @subscriptions.remove subscription
end

#remove_timer(timer) ⇒ Object

Stop a timer

  • timer a timer created by create_timer



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# File 'lib/rclrb/node.rb', line 139

def remove_timer(timer)
  @timers.remove timer
end