#!/usr/bin/env python
#
# License: BSD
# https://raw.githubusercontent.com/splintered-reality/py_trees/devel/LICENSE
#
##############################################################################
# Documentation
##############################################################################
"""
A py_trees demo.
. 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 time
import typing
import py_trees
import py_trees.console as console
##############################################################################
# Classes
##############################################################################
[docs]def description() -> str:
"""
Print description and usage information about the program.
Returns:
the program description string
"""
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 = 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
[docs]def epilog() -> typing.Optional[str]:
"""
Print a noodly epilog for --help.
Returns:
the noodly message
"""
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
[docs]def command_line_argument_parser() -> argparse.ArgumentParser:
"""
Process command line arguments.
Returns:
the argument parser
"""
return argparse.ArgumentParser(
description=description(),
epilog=epilog(),
formatter_class=argparse.RawDescriptionHelpFormatter,
)
[docs]class Counter(py_trees.behaviour.Behaviour):
"""Simple counting behaviour.
* 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: str = "Counter"):
"""Configure the name of the behaviour."""
super(Counter, self).__init__(name)
self.logger.debug("%s.__init__()" % (self.__class__.__name__))
[docs] def setup(self, **kwargs: int) -> None:
"""No delayed initialisation required for this example."""
self.logger.debug("%s.setup()" % (self.__class__.__name__))
[docs] def initialise(self) -> None:
"""Reset a counter variable."""
self.logger.debug("%s.initialise()" % (self.__class__.__name__))
self.counter = 0
[docs] def update(self) -> py_trees.common.Status:
"""Increment the counter and decide on a new status."""
self.counter += 1
new_status = (
py_trees.common.Status.SUCCESS
if self.counter == 3
else py_trees.common.Status.RUNNING
)
if new_status == py_trees.common.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: py_trees.common.Status) -> None:
"""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() -> None:
"""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