Python node for publishing keyboard events

edit

I am trying to build a node in python that publishes key press as strings onto a topic. I am able to print out the keypress on the console, but when I publish it I get this error :(

RuntimeError: maximum recursion depth exceeded

This is all of my code:

class KeyboardPublisher:

def __init__(self):
    # logging the node start
    rospy.loginfo("Starting node keyboard_publisher")

    # Initialise the node
    rospy.init_node("keypress_publisher", anonymous=True)

    # Create a publisher to the keypress topic
    self.keyboard_publisher = rospy.Publisher('/keypress', String, queue_size=1)

def publish_keypress(self, key_press):
    self.publish_keypress(key_press)

def on_press(self, key):
    print(key) #<-- this prints out the key press and then crashes
    self.publish_keypress(key)

def on_release(self, key):
    print('{0} release'.format(
        key))
    if key == Key.esc:
        # Stop listener
        return False

def keyboard_listener(self):
    # Collect events until released
    with Listener(
            on_press=self.on_press,
            on_release=self.on_release) as listener:
        listener.join()


if __name__ == '__main__':
   keyboard_publisher = KeyboardPublisher()
   keyboard_publisher.keyboard_listener()

    try:
      rospy.spin()
    except rospy.ROSInterruptException:
        print("Stopping keyboard_publisher"