#!/usr/bin/env python
#
# License: BSD
# https://raw.githubusercontent.com/stonier/py_trees/devel/LICENSE
#
##############################################################################
# Documentation
##############################################################################
"""
.. argparse::
:module: py_trees.demos.lifecycle
:func: command_line_argument_parser
:prog: py-trees-demo-behaviour-lifecycle
.. image:: images/lifecycle.gif
"""
##############################################################################
# Imports
##############################################################################
import argparse
import py_trees
import time
import py_trees.console as console
##############################################################################
# Classes
##############################################################################
def description():
content = "Demonstrates a typical day in the life of a behaviour.\n\n"
content += "This behaviour will count from 1 to 3 and then reset and repeat. As it does\n"
content += "so, it logs and displays the methods as they are called - construction, setup,\n"
content += "initialisation, ticking and termination.\n"
if py_trees.console.has_colours:
banner_line = console.green + "*" * 79 + "\n" + console.reset
s = "\n"
s += banner_line
s += console.bold_white + "Behaviour Lifecycle".center(79) + "\n" + console.reset
s += banner_line
s += "\n"
s += content
s += "\n"
s += banner_line
else:
s = content
return s
def epilog():
if py_trees.console.has_colours:
return console.cyan + "And his noodly appendage reached forth to tickle the blessed...\n" + console.reset
else:
return None
def command_line_argument_parser():
return argparse.ArgumentParser(description=description(),
epilog=epilog(),
formatter_class=argparse.RawDescriptionHelpFormatter,
)
[docs]class Counter(py_trees.behaviour.Behaviour):
"""
Simple counting behaviour that facilitates the demonstration of a behaviour in
the demo behaviours lifecycle program.
* Increments a counter from zero at each tick
* Finishes with success if the counter reaches three
* Resets the counter in the initialise() method.
"""
[docs] def __init__(self, name="Counter"):
"""
Default construction.
"""
super(Counter, self).__init__(name)
self.logger.debug("%s.__init__()" % (self.__class__.__name__))
[docs] def setup(self, unused_timeout=15):
"""
No delayed initialisation required for this example.
"""
self.logger.debug("%s.setup()" % (self.__class__.__name__))
return True
[docs] def initialise(self):
"""
Reset a counter variable.
"""
self.logger.debug("%s.initialise()" % (self.__class__.__name__))
self.counter = 0
[docs] def update(self):
"""
Increment the counter and decide upon a new status result for the behaviour.
"""
self.counter += 1
new_status = py_trees.Status.SUCCESS if self.counter == 3 else py_trees.Status.RUNNING
if new_status == py_trees.Status.SUCCESS:
self.feedback_message = "counting...{0} - phew, thats enough for today".format(self.counter)
else:
self.feedback_message = "still counting"
self.logger.debug("%s.update()[%s->%s][%s]" % (self.__class__.__name__, self.status, new_status, self.feedback_message))
return new_status
[docs] def terminate(self, new_status):
"""
Nothing to clean up in this example.
"""
self.logger.debug("%s.terminate()[%s->%s]" % (self.__class__.__name__, self.status, new_status))
##############################################################################
# Main
##############################################################################
[docs]def main():
"""
Entry point for the demo script.
"""
command_line_argument_parser().parse_args()
print(description())
py_trees.logging.level = py_trees.logging.Level.DEBUG
counter = Counter()
counter.setup()
try:
for unused_i in range(0, 7):
counter.tick_once()
time.sleep(0.5)
print("\n")
except KeyboardInterrupt:
print("")
pass