class QueuedActionClient:
## @brief Constructs a QueuedActionClient and opens connections to an ActionServer.
##
## @param ns The namespace in which to access the action. For
## example, the "goal" topic should occur under ns/goal
##
## @param ActionSpec The *Action message type. The QueuedActionClient
## will grab the other message types from this type.
def __init__(self, ns, ActionSpec):
self.action_client = ActionClient(ns, ActionSpec)
self.simple_state = SimpleGoalState.DONE
self.gh = None
self.done_condition = threading.Condition()
## @brief Blocks until the action server connects to this client
##
## @param timeout Max time to block before returning. A zero
## timeout is interpreted as an infinite timeout.
##
## @return True if the server connected in the allocated time. False on timeout
def wait_for_server(self, timeout = rospy.Duration()):
return self.action_client.wait_for_server(timeout)
## @brief Sends a goal to the ActionServer, and also registers callbacks
##
## If a previous goal is already active when this is called. We simply forget
## about that goal and start tracking the new goal. No cancel requests are made.
##
## @param done_cb Callback that gets called on transitions to
## Done. The callback should take two parameters: the terminal
## state (as an integer from actionlib_msgs/GoalStatus) and the
## result.
##
## @param active_cb No-parameter callback that gets called on transitions to Active.
##
## @param feedback_cb Callback that gets called whenever feedback
## for this goal is received. Takes one parameter: the feedback.
def send_goal(self, goal, done_cb = None, active_cb = None, feedback_cb = None):
# destroys the old goal handle
self.stop_tracking_goal()
self.done_cb = done_cb
self.active_cb = active_cb
self.feedback_cb = feedback_cb
self.simple_state = SimpleGoalState.PENDING
self.gh = self.action_client.send_goal(goal, self._handle_transition, self._handle_feedback)
## @brief Sends a goal to the ActionServer, waits for the goal to complete, and preempts goal is necessary
##
## If a previous goal is already active when this is called. We simply forget
## about that goal and start tracking the new goal. No cancel requests are made.
##
## If the goal does not complete within the execute_timeout, the goal gets preempted
##
## If preemption of the goal does not complete withing the preempt_timeout, this
## method simply returns
##
## @param execute_timeout The time to wait for the goal to complete
##
## @param preempt_timeout The time to wait for preemption to complete
##
## @return The goal's state.
def send_goal_and_wait(self, goal, execute_timeout = rospy.Duration(), preempt_timeout = rospy.Duration()):
self.send_goal(goal)
if not self.wait_for_result(execute_timeout):
# preempt action
rospy.logdebug("Canceling goal")
self.cancel_goal()
if self.wait_for_result(preempt_timeout):
rospy.logdebug("Preempt finished within specified preempt_timeout [%.2f]", preempt_timeout.to_sec())
else:
rospy.logdebug("Preempt didn't finish specified preempt_timeout [%.2f]", preempt_timeout.to_sec())
return self.get_state()
## @brief Blocks until this goal transitions to done
## @param timeout Max time to block before returning. A zero timeout is interpreted as an infinite timeout.
## @return True if the goal finished. False if the goal didn't finish within the allocated timeout
def wait_for_result(self, timeout = rospy.Duration()):
if not self.gh:
rospy.logerr("Called wait_for_goal_to_finish when no goal exists")
return False
timeout_time = rospy.get_rostime() + timeout
loop_period = rospy.Duration(0.1)
with self.done_condition:
while not rospy.is_shutdown():
time_left = timeout_time - rospy.get_rostime()
if timeout > rospy.Duration(0.0) and time_left <= rospy.Duration(0.0):
break
if self.simple_state == SimpleGoalState.DONE:
break
if time_left > loop_period or timeout == rospy.Duration():
time_left = loop_period
self.done_condition.wait(time_left.to_sec())
return self.simple_state == SimpleGoalState.DONE
## @brief Gets the Result of the current goal
def get_result(self):
if not self.gh:
rospy.logerr("Called get_result when no goal is running")
return None
return self.gh.get_result()
## @brief Get the state information for this goal
##
## Possible States Are: PENDING, ACTIVE, RECALLED, REJECTED,
## PREEMPTED, ABORTED, SUCCEEDED, LOST.
##
## @return The goal's state. Returns LOST if this
## QueuedActionClient isn't tracking a goal.
def get_state(self):
if not self.gh:
rospy.logerr("Called get_state when no goal is running")
return GoalStatus.LOST
status = self.gh.get_goal_status()
if status == GoalStatus.RECALLING:
status = GoalStatus.PENDING
elif status == GoalStatus.PREEMPTING:
status = GoalStatus.ACTIVE
return status
## @brief Returns the current status text of the goal.
##
## The text is sent by the action server. It is designed to
## help debugging issues on the server side.
##
## @return The current status text of the goal.
def get_goal_status_text(self):
if not self.gh:
rospy.logerr("Called get_goal_status_text when no goal is running")
return "ERROR: Called get_goal_status_text when no goal is running"
return self.gh.get_goal_status_text()
## @brief Cancels all goals currently running on the action server
##
## This preempts all goals running on the action server at the point that
## this message is serviced by the ActionServer.
def cancel_all_goals(self):
self.action_client.cancel_all_goals()
## @brief Cancels all goals prior to a given timestamp
##
## This preempts all goals running on the action server for which the
## time stamp is earlier than the specified time stamp
## this message is serviced by the ActionServer.
def cancel_goals_at_and_before_time(self, time):
self.action_client.cancel_goals_at_and_before_time(time)
## @brief Cancels the goal that we are currently pursuing
def cancel_goal(self):
if self.gh:
self.gh.cancel()
## @brief Stops tracking the state of the current goal. Unregisters this goal's callbacks
##
## This is useful if we want to make sure we stop calling our callbacks before sending a new goal.
## Note that this does not cancel the goal, it simply stops looking for status info about this goal.
def stop_tracking_goal(self):
self.gh = None
def _handle_transition(self, gh):
comm_state = gh.get_comm_state()
error_msg = "Received comm state %s when in simple state %s with QueuedActionClient in NS %s" % \
(CommState.to_string(comm_state), SimpleGoalState.to_string(self.simple_state), rospy.resolve_name(self.action_client.ns))
if comm_state == CommState.ACTIVE:
if self.simple_state == SimpleGoalState.PENDING:
self._set_simple_state(SimpleGoalState.ACTIVE)
if self.active_cb:
self.active_cb()
elif self.simple_state == SimpleGoalState.DONE:
rospy.logerr(error_msg)
elif comm_state == CommState.RECALLING:
if self.simple_state != SimpleGoalState.PENDING:
rospy.logerr(error_msg)
elif comm_state == CommState.PREEMPTING:
if self.simple_state == SimpleGoalState.PENDING:
self._set_simple_state(SimpleGoalState.ACTIVE)
if self.active_cb:
self.active_cb()
elif self.simple_state == SimpleGoalState.DONE:
rospy.logerr(error_msg)
elif comm_state == CommState.DONE:
if self.simple_state in [SimpleGoalState.PENDING, SimpleGoalState.ACTIVE]:
self._set_simple_state(SimpleGoalState.DONE)
if self.done_cb:
self.done_cb(gh.get_goal_status(), gh.get_result())
with self.done_condition:
self.done_condition.notifyAll()
elif self.simple_state == SimpleGoalState.DONE:
rospy.logerr("QueuedActionClient received DONE twice")
def _handle_feedback(self, gh, feedback):
if not self.gh:
rospy.logerr("Got a feedback callback when we're not tracking a goal. (id: %s)" % \
gh.comm_state_machine.action_goal.goal_id.id)
return
if gh != self.gh:
rospy.logerr("Got a feedback callback on a goal handle that we're not tracking. %s vs %s" % \
(self.gh.comm_state_machine.action_goal.goal_id.id,
gh.comm_state_machine.action_goal.goal_id.id))
return
if self.feedback_cb:
self.feedback_cb(feedback)
def _set_simple_state(self, state):
self.simple_state = state
class SimpleActionClient:
## @brief Constructs a SimpleActionClient and opens connections to an ActionServer.
##
## @param ns The namespace in which to access the action. For
## example, the "goal" topic should occur under ns/goal
##
## @param ActionSpec The *Action message type. The SimpleActionClient
## will grab the other message types from this type.
def __init__(self, ns, ActionSpec):
self.action_client = ActionClient(ns, ActionSpec)
self.simple_state = SimpleGoalState.DONE
self.gh = None
self.done_condition = threading.Condition()
## @brief [Deprecated] Use wait_for_server
def wait_for_action_server_to_start(self, timeout=rospy.Duration()):
return self.wait_for_server(timeout)
## @brief Blocks until the action server connects to this client
##
## @param timeout Max time to block before returning. A zero
## timeout is interpreted as an infinite timeout.
##
## @return True if the server connected in the allocated time. False on timeout
def wait_for_server(self, timeout=rospy.Duration()):
return self.action_client.wait_for_server(timeout)
## @brief Sends a goal to the ActionServer, and also registers callbacks
##
## If a previous goal is already active when this is called. We simply forget
## about that goal and start tracking the new goal. No cancel requests are made.
##
## @param done_cb Callback that gets called on transitions to
## Done. The callback should take two parameters: the terminal
## state (as an integer from actionlib_msgs/GoalStatus) and the
## result.
##
## @param active_cb No-parameter callback that gets called on transitions to Active.
##
## @param feedback_cb Callback that gets called whenever feedback
## for this goal is received. Takes one parameter: the feedback.
def send_goal(self, goal, done_cb=None, active_cb=None, feedback_cb=None):
# destroys the old goal handle
self.stop_tracking_goal()
self.done_cb = done_cb
self.active_cb = active_cb
self.feedback_cb = feedback_cb
self.simple_state = SimpleGoalState.PENDING
self.gh = self.action_client.send_goal(goal, self._handle_transition,
self._handle_feedback)
## @brief [Deprecated] Use wait_for_result
def wait_for_goal_to_finish(self, timeout=rospy.Duration()):
return self.wait_for_result(timeout)
## @brief Blocks until this goal transitions to done
## @param timeout Max time to block before returning. A zero timeout is interpreted as an infinite timeout.
## @return True if the goal finished. False if the goal didn't finish within the allocated timeout
def wait_for_result(self, timeout=rospy.Duration()):
if not self.gh:
rospy.logerr("Called wait_for_goal_to_finish when no goal exists")
return False
timeout_time = rospy.get_rostime() + timeout
loop_period = rospy.Duration(0.1)
self.done_condition.acquire()
while not rospy.is_shutdown():
time_left = timeout_time - rospy.get_rostime()
if timeout > rospy.Duration(0.0) and time_left <= rospy.Duration(
0.0):
break
if self.simple_state == SimpleGoalState.DONE:
break
if time_left > loop_period:
time_left = loop_period
self.done_condition.wait(time_left.to_seconds())
self.done_condition.release()
return self.simple_state == SimpleGoalState.DONE
## @brief [Deprecated] Gets the current state of the goal: [PENDING], [ACTIVE], or [DONE]
##
## Deprecated. Use get_state instead
def get_goal_state(self):
rospy.logwarn("SimpleActionClient.get_goal_state has been deprecated")
if not self.gh:
rospy.logerr("Called get_goal_state when no goal is running")
return SimpleGoalState.DONE
comm_state = self.gh.get_comm_state()
if comm_state in [
CommState.WAITING_FOR_GOAL_ACK, CommState.PENDING,
CommState.RECALLING
]:
return SimpleGoalState.PENDING
elif comm_state in [CommState.ACTIVE, CommState.PREEMPTING]:
return SimpleGoalState.ACTIVE
elif comm_state in [CommState.DONE]:
return SimpleGoalState.DONE
elif comm_state in [
CommState.WAITING_FOR_RESULT, CommState.WAITING_FOR_CANCEL_ACK
]:
return self.simple_state
rospy.logerr(
"Error trying to interpret CommState in get_goal_state: %i" %
comm_state)
return SimpleGoalState.DONE
## @brief Gets the Result of the current goal
def get_result(self):
if not self.gh:
rospy.logerr("Called get_result when no goal is running")
return None
return self.gh.get_result()
## @brief [Deprecated] Get the terminal state information for this goal
##
## Deprecated. Use get_state instead.
##
## Possible States Are: RECALLED, REJECTED, PREEMPTED, ABORTED,
## SUCCEEDED, LOST. This call only makes sense if
## SimpleGoalState==DONE. This will sends ROS_WARNs if we're not
## in DONE
##
## @return The terminal state
def get_terminal_state(self):
rospy.logwarn(
"SimpleactionClient.get_terminal_state has been deprecated")
if not self.gh:
rospy.logerr("Called get_terminal_state when no goal is running")
return GoalStatus.LOST
return self.gh.get_terminal_state()
## @brief Get the state information for this goal
##
## Possible States Are: PENDING, ACTIVE, RECALLED, REJECTED,
## PREEMPTED, ABORTED, SUCCEEDED, LOST.
##
## @return The goal's state. Returns LOST if this
## SimpleActionClient isn't tracking a goal.
def get_state(self):
if not self.gh:
rospy.logerr("Called get_state when no goal is running")
return GoalStatus.LOST
status = gh.get_goal_status()
if status == GoalStatus.RECALLING:
status = GoalStatus.PENDING
elif status == GoalStatus.PREEMPTING:
status = GoalStatus.ACTIVE
return status
## @brief Cancels all goals currently running on the action server
##
## This preempts all goals running on the action server at the point that
## this message is serviced by the ActionServer.
def cancel_all_goals(self):
self.action_client.cancel_all_goals()
## @brief Cancels the goal that we are currently pursuing
def cancel_goal(self):
if self.gh:
self.gh.cancel()
## @brief Stops tracking the state of the current goal. Unregisters this goal's callbacks
##
## This is useful if we want to make sure we stop calling our callbacks before sending a new goal.
## Note that this does not cancel the goal, it simply stops looking for status info about this goal.
def stop_tracking_goal(self):
del self.gh
self.gh = None
def _handle_transition(self, gh):
comm_state = self.gh.get_comm_state()
error_msg = "Received comm state %s when in simple state %s" % \
(CommState.to_string(comm_state), SimpleGoalState.to_string(self.simple_state))
if comm_state == CommState.ACTIVE:
if self.simple_state == SimpleGoalState.PENDING:
self._set_simple_state(SimpleGoalState.ACTIVE)
if self.active_cb:
self.active_cb()
elif self.simple_state == SimpleGoalState.DONE:
rospy.logerr(error_msg)
elif comm_state == CommState.RECALLING:
if self.simple_state != SimpleGoalState.PENDING:
rospy.logerr(error_msg)
elif comm_state == CommState.PREEMPTING:
if self.simple_state == SimpleGoalState.PENDING:
self._set_simple_state(SimpleGoalState.ACTIVE)
if self.active_cb:
self.active_cb()
elif self.simple_state == SimpleGoalState.DONE:
rospy.logerr(error_msg)
elif comm_state == CommState.DONE:
if self.simple_state in [
SimpleGoalState.PENDING, SimpleGoalState.ACTIVE
]:
self._set_simple_state(SimpleGoalState.DONE)
if self.done_cb:
self.done_cb(self.gh.get_goal_status(),
self.gh.get_result())
self.done_condition.acquire()
self.done_condition.notifyAll()
self.done_condition.release()
elif self.simple_state == SimpleGoalState.DONE:
rospy.logerr("SimpleActionClient received DONE twice")
def _handle_feedback(self, gh, feedback):
if gh != self.gh:
rospy.logerr(
"Got a feedback callback on a goal handle that we're not tracking. %s vs %s"
% (self.gh.comm_state_machine.action_goal.goal_id.id,
gh.comm_state_machine.action_goal.goal_id.id))
return
if self.feedback_cb:
self.feedback_cb(feedback)
def _set_simple_state(self, state):
self.simple_state = state