def internal_goal_callback(self, goal):
with self.lock:
# if we're not started... then we're not actually going to do anything
if not self.started:
return
rospy.logdebug("The action server has received a new goal request")
# we need to check if this goal already lives in the status list
for st in self.status_list[:]:
if goal.goal_id.id == st.status.goal_id.id:
rospy.logdebug(
"Goal %s was already in the status list with status %i"
% (goal.goal_id.id, st.status.status))
# Goal could already be in recalling state if a cancel came in before the goal
if st.status.status == actionlib_msgs.msg.GoalStatus.RECALLING:
st.status.status = actionlib_msgs.msg.GoalStatus.RECALLED
self.publish_result(st.status, self.ActionResultType())
# if this is a request for a goal that has no active handles left,
# we'll bump how long it stays in the list
if st.handle_tracker is None:
st.handle_destruction_time = rospy.Time.now()
# make sure not to call any user callbacks or add duplicate status onto the list
return
# if the goal is not in our list, we need to create a StatusTracker associated with this goal and push it on
st = StatusTracker(None, None, goal)
self.status_list.append(st)
# we need to create a handle tracker for the incoming goal and update the StatusTracker
handle_tracker = HandleTrackerDeleter(self, st)
st.handle_tracker = handle_tracker
# check if this goal has already been canceled based on its timestamp
gh = ServerGoalHandle(st, self, handle_tracker)
if goal.goal_id.stamp != rospy.Time(
) and goal.goal_id.stamp <= self.last_cancel:
# if it has... just create a GoalHandle for it and setCanceled
gh.set_canceled(
None,
"This goal handle was canceled by the action server because its timestamp is before the timestamp of the last cancel request"
)
else:
# now, we need to create a goal handle and call the user's callback
self.goal_callback(gh)
def internal_goal_callback(self, goal):
with self.lock:
#if we're not started... then we're not actually going to do anything
if not self.started:
return;
rospy.logdebug("The action server has received a new goal request");
#we need to check if this goal already lives in the status list
for st in self.status_list[:]:
if goal.goal_id.id == st.status.goal_id.id:
rospy.logdebug("Goal %s was already in the status list with status %i" % (goal.goal_id.id, st.status.status))
# Goal could already be in recalling state if a cancel came in before the goal
if st.status.status == actionlib_msgs.msg.GoalStatus.RECALLING:
st.status.status = actionlib_msgs.msg.GoalStatus.RECALLED
self.publish_result(st.status, self.ActionResultType())
#if this is a request for a goal that has no active handles left,
#we'll bump how long it stays in the list
if st.handle_tracker is None:
st.handle_destruction_time = rospy.Time.now()
#make sure not to call any user callbacks or add duplicate status onto the list
return;
#if the goal is not in our list, we need to create a StatusTracker associated with this goal and push it on
st = StatusTracker(None,None,goal)
self.status_list.append(st);
#we need to create a handle tracker for the incoming goal and update the StatusTracker
handle_tracker = HandleTrackerDeleter(self, st);
st.handle_tracker = handle_tracker;
#check if this goal has already been canceled based on its timestamp
gh= ServerGoalHandle(st, self, handle_tracker);
if goal.goal_id.stamp != rospy.Time() and goal.goal_id.stamp <= self.last_cancel:
#if it has... just create a GoalHandle for it and setCanceled
gh.set_canceled(None, "This goal handle was canceled by the action server because its timestamp is before the timestamp of the last cancel request");
else:
#now, we need to create a goal handle and call the user's callback
self.goal_callback(gh);
class SimpleActionServer:
## @brief Constructor for a SimpleActionServer
## @param name A name for the action server
## @param execute_cb Optional callback that gets called in a separate thread whenever
## a new goal is received, allowing users to have blocking callbacks.
## Adding an execute callback also deactivates the goalCallback.
## @param auto_start A boolean value that tells the ActionServer wheteher or not to start publishing as soon as it comes up. THIS SHOULD ALWAYS BE SET TO FALSE TO AVOID RACE CONDITIONS and start() should be called after construction of the server.
def __init__(self, name, ActionSpec, execute_cb = None, auto_start = True):
self.new_goal = False
self.preempt_request = False
self.new_goal_preempt_request = False
self.execute_callback = execute_cb;
self.goal_callback = None;
self.preempt_callback = None;
self.need_to_terminate = False
self.terminate_mutex = threading.RLock();
# since the internal_goal/preempt_callbacks are invoked from the
# ActionServer while holding the self.action_server.lock
# self.lock must always be locked after the action server lock
# to avoid an inconsistent lock acquisition order
self.lock = threading.RLock();
self.execute_condition = threading.Condition(self.lock);
self.current_goal = ServerGoalHandle();
self.next_goal = ServerGoalHandle();
if self.execute_callback:
self.execute_thread = threading.Thread(None, self.executeLoop);
self.execute_thread.start();
else:
self.execute_thread = None
#create the action server
self.action_server = ActionServer(name, ActionSpec, self.internal_goal_callback,self.internal_preempt_callback,auto_start);
def __del__(self):
if hasattr(self, 'execute_callback') and self.execute_callback:
with self.terminate_mutex:
self.need_to_terminate = True;
assert(self.execute_thread);
self.execute_thread.join();
## @brief Accepts a new goal when one is available The status of this
## goal is set to active upon acceptance, and the status of any
## previously active goal is set to preempted. Preempts received for the
## new goal between checking if isNewGoalAvailable or invokation of a
## goal callback and the acceptNewGoal call will not trigger a preempt
## callback. This means, isPreemptReqauested should be called after
## accepting the goal even for callback-based implementations to make
## sure the new goal does not have a pending preempt request.
## @return A shared_ptr to the new goal.
def accept_new_goal(self):
with self.action_server.lock, self.lock:
if not self.new_goal or not self.next_goal.get_goal():
rospy.logerr("Attempting to accept the next goal when a new goal is not available");
return None;
#check if we need to send a preempted message for the goal that we're currently pursuing
if self.is_active() and self.current_goal.get_goal() and self.current_goal != self.next_goal:
self.current_goal.set_canceled(None, "This goal was canceled because another goal was received by the simple action server");
rospy.logdebug("Accepting a new goal");
#accept the next goal
self.current_goal = self.next_goal;
self.new_goal = False;
#set preempt to request to equal the preempt state of the new goal
self.preempt_request = self.new_goal_preempt_request;
self.new_goal_preempt_request = False;
#set the status of the current goal to be active
self.current_goal.set_accepted("This goal has been accepted by the simple action server");
return self.current_goal.get_goal();
## @brief Allows polling implementations to query about the availability of a new goal
## @return True if a new goal is available, false otherwise
def is_new_goal_available(self):
return self.new_goal;
## @brief Allows polling implementations to query about preempt requests
## @return True if a preempt is requested, false otherwise
def is_preempt_requested(self):
return self.preempt_request;
## @brief Allows polling implementations to query about the status of the current goal
## @return True if a goal is active, false otherwise
def is_active(self):
if not self.current_goal.get_goal():
return False;
status = self.current_goal.get_goal_status().status;
return status == actionlib_msgs.msg.GoalStatus.ACTIVE or status == actionlib_msgs.msg.GoalStatus.PREEMPTING;
## @brief Sets the status of the active goal to succeeded
## @param result An optional result to send back to any clients of the goal
def set_succeeded(self,result=None, text=""):
with self.action_server.lock, self.lock:
if not result:
result=self.get_default_result();
self.current_goal.set_succeeded(result, text);
## @brief Sets the status of the active goal to aborted
## @param result An optional result to send back to any clients of the goal
def set_aborted(self, result = None, text=""):
with self.action_server.lock, self.lock:
if not result:
result=self.get_default_result();
self.current_goal.set_aborted(result, text);
## @brief Publishes feedback for a given goal
## @param feedback Shared pointer to the feedback to publish
def publish_feedback(self,feedback):
self.current_goal.publish_feedback(feedback);
def get_default_result(self):
return self.action_server.ActionResultType();
## @brief Sets the status of the active goal to preempted
## @param result An optional result to send back to any clients of the goal
def set_preempted(self,result=None, text=""):
if not result:
result=self.get_default_result();
with self.action_server.lock, self.lock:
rospy.logdebug("Setting the current goal as canceled");
self.current_goal.set_canceled(result, text);
## @brief Allows users to register a callback to be invoked when a new goal is available
## @param cb The callback to be invoked
def register_goal_callback(self,cb):
if self.execute_callback:
rospy.logwarn("Cannot call SimpleActionServer.register_goal_callback() because an executeCallback exists. Not going to register it.");
else:
self.goal_callback = cb;
## @brief Allows users to register a callback to be invoked when a new preempt request is available
## @param cb The callback to be invoked
def register_preempt_callback(self, cb):
self.preempt_callback = cb;
## @brief Explicitly start the action server, used it auto_start is set to false
def start(self):
self.action_server.start();
## @brief Callback for when the ActionServer receives a new goal and passes it on
def internal_goal_callback(self, goal):
self.execute_condition.acquire();
try:
rospy.logdebug("A new goal %shas been recieved by the single goal action server",goal.get_goal_id().id);
#check that the timestamp is past that of the current goal and the next goal
if((not self.current_goal.get_goal() or goal.get_goal_id().stamp >= self.current_goal.get_goal_id().stamp)
and (not self.next_goal.get_goal() or goal.get_goal_id().stamp >= self.next_goal.get_goal_id().stamp)):
#if next_goal has not been accepted already... its going to get bumped, but we need to let the client know we're preempting
if(self.next_goal.get_goal() and (not self.current_goal.get_goal() or self.next_goal != self.current_goal)):
self.next_goal.set_canceled(None, "This goal was canceled because another goal was received by the simple action server");
self.next_goal = goal;
self.new_goal = True;
self.new_goal_preempt_request = False;
#if the server is active, we'll want to call the preempt callback for the current goal
if(self.is_active()):
self.preempt_request = True;
#if the user has registered a preempt callback, we'll call it now
if(self.preempt_callback):
self.preempt_callback();
#if the user has defined a goal callback, we'll call it now
if self.goal_callback:
self.goal_callback();
#Trigger runLoop to call execute()
self.execute_condition.notify();
self.execute_condition.release();
else:
#the goal requested has already been preempted by a different goal, so we're not going to execute it
goal.set_canceled(None, "This goal was canceled because another goal was received by the simple action server");
self.execute_condition.release();
except Exception, e:
rospy.logerr("SimpleActionServer.internal_goal_callback - exception %s",str(e))
self.execute_condition.release();
class QueuedActionServer:
## @brief Constructor for a QueuedActionServer
## @param name A name for the action server
## @param execute_cb Optional callback that gets called in a separate thread whenever
## a new goal is received, allowing users to have blocking callbacks.
## Adding an execute callback also deactivates the goalCallback.
## @param auto_start A boolean value that tells the ActionServer wheteher or not to start publishing as soon as it comes up. THIS SHOULD ALWAYS BE SET TO FALSE TO AVOID RACE CONDITIONS and start() should be called after construction of the server.
def __init__(self, name, ActionSpec, execute_cb = None, auto_start = True):
self.new_goal = False
self.preempt_request = False
self.new_goal_preempt_request = False
self.maxlen = 5
#self.goals_buf = deque(maxlen=5)
self.goals_buf = Queue.Queue(maxsize=self.maxlen)
self.current_indexA = 0
self.current_indexP = 0
#self.maxlen = self.goals_buf.maxlen
self.execute_callback = execute_cb
self.goal_callback = None
self.preempt_callback = None
self.need_to_terminate = False
self.terminate_mutex = threading.RLock()
self.lock = threading.RLock()
self.execute_condition = threading.Condition(self.lock)
self.current_goal = ServerGoalHandle()
self.next_goal = ServerGoalHandle()
if self.execute_callback:
self.execute_thread = threading.Thread(None, self.executeLoop)
self.execute_thread.start()
else:
self.execute_thread = None
#create the action server
self.action_server = ActionServer(name, ActionSpec, self.internal_goal_callback,self.internal_preempt_callback,auto_start)
def __del__(self):
if hasattr(self, 'execute_callback') and self.execute_callback:
with self.terminate_mutex:
self.need_to_terminate = True
assert(self.execute_thread)
self.execute_thread.join()
## @brief Accepts a new goal when one is available The status of this
## goal is set to active upon acceptance, and the status of any
## previously active goal is set to preempted. Preempts received for the
## new goal between checking if isNewGoalAvailable or invokation of a
## goal callback and the acceptNewGoal call will not trigger a preempt
## callback. This means, isPreemptReqauested should be called after
## accepting the goal even for callback-based implementations to make
## sure the new goal does not have a pending preempt request.
## @return A shared_ptr to the new goal.
def accept_new_goal(self):
with self.lock:
if not self.new_goal or not self.next_goal.get_goal():
rospy.logerr("Attempting to accept the next goal when a new goal is not available")
return None
rospy.logdebug("Accepting a new goal")
#accept the next goal
self.current_goal = self.next_goal
self.new_goal = False
#set preempt to request to equal the preempt state of the new goal
self.preempt_request = self.new_goal_preempt_request
self.new_goal_preempt_request = False
#set the status of the current goal to be active
self.current_goal.set_accepted("This goal has been accepted by the queued action server")
return self.current_goal.get_goal()
## @brief Allows polling implementations to query about the availability of a new goal
## @return True if a new goal is available, false otherwise
def is_new_goal_available(self):
return self.new_goal
## @brief Allows polling implementations to query about preempt requests
## @return True if a preempt is requested, false otherwise
def is_preempt_requested(self):
return self.preempt_request
## @brief Allows polling implementations to query about the status of the current goal
## @return True if a goal is active, false otherwise
def is_active(self):
if not self.current_goal.get_goal():
return False
status = self.current_goal.get_goal_status().status
return status == actionlib_msgs.msg.GoalStatus.ACTIVE or status == actionlib_msgs.msg.GoalStatus.PREEMPTING
## @brief Sets the status of the active goal to succeeded
## @param result An optional result to send back to any clients of the goal
def set_succeeded(self,result=None, text=""):
with self.lock:
if not result:
result=self.get_default_result()
self.current_goal.set_succeeded(result, text)
## @brief Sets the status of the active goal to aborted
## @param result An optional result to send back to any clients of the goal
def set_aborted(self, result = None, text=""):
with self.lock:
if not result:
result=self.get_default_result()
self.current_goal.set_aborted(result, text)
## @brief Publishes feedback for a given goal
## @param feedback Shared pointer to the feedback to publish
def publish_feedback(self,feedback):
self.current_goal.publish_feedback(feedback)
def get_default_result(self):
return self.action_server.ActionResultType()
## @brief Sets the status of the active goal to preempted
## @param result An optional result to send back to any clients of the goal
def set_preempted(self,result=None, text=""):
if not result:
result=self.get_default_result()
with self.lock:
rospy.logdebug("Setting the current goal as canceled")
self.current_goal.set_canceled(result, text)
## @brief Allows users to register a callback to be invoked when a new goal is available
## @param cb The callback to be invoked
def register_goal_callback(self,cb):
if self.execute_callback:
rospy.logwarn("Cannot call QueuedActionServer.register_goal_callback() because an executeCallback exists. Not going to register it.")
else:
self.goal_callback = cb
## @brief Allows users to register a callback to be invoked when a new preempt request is available
## @param cb The callback to be invoked
def register_preempt_callback(self, cb):
self.preempt_callback = cb
## @brief Explicitly start the action server, used it auto_start is set to false
def start(self):
self.action_server.start()
## @brief Callback for when the ActionServer receives a new goal and passes it on
def internal_goal_callback(self, goal):
self.execute_condition.acquire()
try:
rospy.logdebug("A new goal %shas been recieved by the Queued goal action server",goal.get_goal_id().id)
if(self.goals_buf.empty()):
self.new_goal = True
self.next_goal = goal
self.goals_buf.put(goal, timeout=1)
else:
self.goals_buf.put(goal, timeout=1)
rospy.loginfo("Queued New Goal")
if self.goal_callback:
self.goal_callback()
#rospy.loginfo("Goals List-----------------------------------------------")
#for item in self.goals_buf:
# rospy.loginfo("Goals Buffer%s" %item.get_goal_status())
#rospy.loginfo("End of the Goals List-------------------------------------")
#if the user has defined a goal callback, we'll call it now
#Trigger runLoop to call execute()
self.execute_condition.notify()
self.execute_condition.release()
except Exception, e:
rospy.logerr("QueuedActionServer.internal_goal_callback - exception %s",str(e))
self.execute_condition.release()
class SimpleActionServer:
## @brief Constructor for a SimpleActionServer
## @param name A name for the action server
## @param execute_cb Optional callback that gets called in a separate thread whenever
## a new goal is received, allowing users to have blocking callbacks.
## Adding an execute callback also deactivates the goalCallback.
## @param auto_start A boolean value that tells the ActionServer wheteher or not to start publishing as soon as it comes up. THIS SHOULD ALWAYS BE SET TO FALSE TO AVOID RACE CONDITIONS and start() should be called after construction of the server.
def __init__(self, name, ActionSpec, execute_cb=None, auto_start=True):
self.new_goal = False
self.preempt_request = False
self.new_goal_preempt_request = False
self.execute_callback = execute_cb
self.goal_callback = None
self.preempt_callback = None
self.need_to_terminate = False
self.terminate_mutex = threading.RLock()
# since the internal_goal/preempt_callbacks are invoked from the
# ActionServer while holding the self.action_server.lock
# self.lock must always be locked after the action server lock
# to avoid an inconsistent lock acquisition order
self.lock = threading.RLock()
self.execute_condition = threading.Condition(self.lock)
self.current_goal = ServerGoalHandle()
self.next_goal = ServerGoalHandle()
if self.execute_callback:
self.execute_thread = threading.Thread(None, self.executeLoop)
self.execute_thread.start()
else:
self.execute_thread = None
#create the action server
self.action_server = ActionServer(name, ActionSpec,
self.internal_goal_callback,
self.internal_preempt_callback,
auto_start)
def __del__(self):
if hasattr(self, 'execute_callback') and self.execute_callback:
with self.terminate_mutex:
self.need_to_terminate = True
assert (self.execute_thread)
self.execute_thread.join()
## @brief Accepts a new goal when one is available The status of this
## goal is set to active upon acceptance, and the status of any
## previously active goal is set to preempted. Preempts received for the
## new goal between checking if isNewGoalAvailable or invokation of a
## goal callback and the acceptNewGoal call will not trigger a preempt
## callback. This means, isPreemptReqauested should be called after
## accepting the goal even for callback-based implementations to make
## sure the new goal does not have a pending preempt request.
## @return A shared_ptr to the new goal.
def accept_new_goal(self):
with self.action_server.lock, self.lock:
if not self.new_goal or not self.next_goal.get_goal():
rospy.logerr(
"Attempting to accept the next goal when a new goal is not available"
)
return None
# check if we need to send a preempted message for the goal that we're currently pursuing
if self.is_active() and self.current_goal.get_goal(
) and self.current_goal != self.next_goal:
self.current_goal.set_canceled(
None,
"This goal was canceled because another goal was received by the simple action server"
)
rospy.logdebug("Accepting a new goal")
# accept the next goal
self.current_goal = self.next_goal
self.new_goal = False
# set preempt to request to equal the preempt state of the new goal
self.preempt_request = self.new_goal_preempt_request
self.new_goal_preempt_request = False
# set the status of the current goal to be active
self.current_goal.set_accepted(
"This goal has been accepted by the simple action server")
return self.current_goal.get_goal()
## @brief Allows polling implementations to query about the availability of a new goal
## @return True if a new goal is available, false otherwise
def is_new_goal_available(self):
return self.new_goal
## @brief Allows polling implementations to query about preempt requests
## @return True if a preempt is requested, false otherwise
def is_preempt_requested(self):
return self.preempt_request
## @brief Allows polling implementations to query about the status of the current goal
## @return True if a goal is active, false otherwise
def is_active(self):
if not self.current_goal.get_goal():
return False
status = self.current_goal.get_goal_status().status
return status == actionlib_msgs.msg.GoalStatus.ACTIVE or status == actionlib_msgs.msg.GoalStatus.PREEMPTING
## @brief Sets the status of the active goal to succeeded
## @param result An optional result to send back to any clients of the goal
def set_succeeded(self, result=None, text=""):
with self.action_server.lock, self.lock:
if not result:
result = self.get_default_result()
self.current_goal.set_succeeded(result, text)
## @brief Sets the status of the active goal to aborted
## @param result An optional result to send back to any clients of the goal
def set_aborted(self, result=None, text=""):
with self.action_server.lock, self.lock:
if not result:
result = self.get_default_result()
self.current_goal.set_aborted(result, text)
## @brief Publishes feedback for a given goal
## @param feedback Shared pointer to the feedback to publish
def publish_feedback(self, feedback):
self.current_goal.publish_feedback(feedback)
def get_default_result(self):
return self.action_server.ActionResultType()
## @brief Sets the status of the active goal to preempted
## @param result An optional result to send back to any clients of the goal
def set_preempted(self, result=None, text=""):
if not result:
result = self.get_default_result()
with self.action_server.lock, self.lock:
rospy.logdebug("Setting the current goal as canceled")
self.current_goal.set_canceled(result, text)
## @brief Allows users to register a callback to be invoked when a new goal is available
## @param cb The callback to be invoked
def register_goal_callback(self, cb):
if self.execute_callback:
rospy.logwarn(
"Cannot call SimpleActionServer.register_goal_callback() because an executeCallback exists. Not going to register it."
)
else:
self.goal_callback = cb
## @brief Allows users to register a callback to be invoked when a new preempt request is available
## @param cb The callback to be invoked
def register_preempt_callback(self, cb):
self.preempt_callback = cb
## @brief Explicitly start the action server, used it auto_start is set to false
def start(self):
self.action_server.start()
## @brief Callback for when the ActionServer receives a new goal and passes it on
def internal_goal_callback(self, goal):
self.execute_condition.acquire()
try:
rospy.logdebug(
"A new goal %shas been recieved by the single goal action server",
goal.get_goal_id().id)
# check that the timestamp is past that of the current goal and the next goal
if ((not self.current_goal.get_goal() or goal.get_goal_id().stamp
>= self.current_goal.get_goal_id().stamp) and
(not self.next_goal.get_goal() or goal.get_goal_id().stamp >=
self.next_goal.get_goal_id().stamp)):
# if next_goal has not been accepted already... its going to get bumped, but we need to let the client know we're preempting
if (self.next_goal.get_goal()
and (not self.current_goal.get_goal()
or self.next_goal != self.current_goal)):
self.next_goal.set_canceled(
None,
"This goal was canceled because another goal was received by the simple action server"
)
self.next_goal = goal
self.new_goal = True
self.new_goal_preempt_request = False
# if the server is active, we'll want to call the preempt callback for the current goal
if (self.is_active()):
self.preempt_request = True
# if the user has registered a preempt callback, we'll call it now
if (self.preempt_callback):
self.preempt_callback()
# if the user has defined a goal callback, we'll call it now
if self.goal_callback:
self.goal_callback()
# Trigger runLoop to call execute()
self.execute_condition.notify()
self.execute_condition.release()
else:
# the goal requested has already been preempted by a different goal, so we're not going to execute it
goal.set_canceled(
None,
"This goal was canceled because another goal was received by the simple action server"
)
self.execute_condition.release()
except Exception as e:
rospy.logerr(
"SimpleActionServer.internal_goal_callback - exception %s",
str(e))
self.execute_condition.release()
## @brief Callback for when the ActionServer receives a new preempt and passes it on
def internal_preempt_callback(self, preempt):
with self.lock:
rospy.logdebug(
"A preempt has been received by the SimpleActionServer")
#if the preempt is for the current goal, then we'll set the preemptRequest flag and call the user's preempt callback
if (preempt == self.current_goal):
rospy.logdebug(
"Setting preempt_request bit for the current goal to TRUE and invoking callback"
)
self.preempt_request = True
#if the user has registered a preempt callback, we'll call it now
if (self.preempt_callback):
self.preempt_callback()
#if the preempt applies to the next goal, we'll set the preempt bit for that
elif (preempt == self.next_goal):
rospy.logdebug(
"Setting preempt request bit for the next goal to TRUE")
self.new_goal_preempt_request = True
## @brief Called from a separate thread to call blocking execute calls
def executeLoop(self):
loop_duration = rospy.Duration.from_sec(.1)
while (not rospy.is_shutdown()):
with self.terminate_mutex:
if (self.need_to_terminate):
break
# the following checks (is_active, is_new_goal_available)
# are performed without locking
# the worst thing that might happen in case of a race
# condition is a warning/error message on the console
if (self.is_active()):
rospy.logerr(
"Should never reach this code with an active goal")
return
if (self.is_new_goal_available()):
# accept_new_goal() is performing its own locking
goal = self.accept_new_goal()
if not self.execute_callback:
rospy.logerr(
"execute_callback_ must exist. This is a bug in SimpleActionServer"
)
return
try:
self.execute_callback(goal)
if self.is_active():
rospy.logwarn(
"Your executeCallback did not set the goal to a terminal status. "
+
"This is a bug in your ActionServer implementation. Fix your code! "
+
"For now, the ActionServer will set this goal to aborted"
)
self.set_aborted(None, "No terminal state was set.")
except Exception as ex:
rospy.logerr("Exception in your execute callback: %s\n%s",
str(ex), traceback.format_exc())
self.set_aborted(
None, "Exception in execute callback: %s" % str(ex))
with self.execute_condition:
self.execute_condition.wait(loop_duration.to_sec())
class QueuedActionServer:
## @brief Constructor for a QueuedActionServer
## @param name A name for the action server
## @param execute_cb Optional callback that gets called in a separate thread whenever
## a new goal is received, allowing users to have blocking callbacks.
## Adding an execute callback also deactivates the goalCallback.
## @param auto_start A boolean value that tells the ActionServer wheteher or not to start publishing as soon as it comes up. THIS SHOULD ALWAYS BE SET TO FALSE TO AVOID RACE CONDITIONS and start() should be called after construction of the server.
def __init__(self, name, ActionSpec, execute_cb=None, auto_start=True):
self.new_goal = False
self.preempt_request = False
self.new_goal_preempt_request = False
self.maxlen = 5
#self.goals_buf = deque(maxlen=5)
self.goals_buf = Queue.Queue(maxsize=self.maxlen)
self.current_indexA = 0
self.current_indexP = 0
#self.maxlen = self.goals_buf.maxlen
self.execute_callback = execute_cb
self.goal_callback = None
self.preempt_callback = None
self.need_to_terminate = False
self.terminate_mutex = threading.RLock()
self.lock = threading.RLock()
self.execute_condition = threading.Condition(self.lock)
self.current_goal = ServerGoalHandle()
self.next_goal = ServerGoalHandle()
if self.execute_callback:
self.execute_thread = threading.Thread(None, self.executeLoop)
self.execute_thread.start()
else:
self.execute_thread = None
#create the action server
self.action_server = ActionServer(name, ActionSpec,
self.internal_goal_callback,
self.internal_preempt_callback,
auto_start)
def __del__(self):
if hasattr(self, 'execute_callback') and self.execute_callback:
with self.terminate_mutex:
self.need_to_terminate = True
assert (self.execute_thread)
self.execute_thread.join()
## @brief Accepts a new goal when one is available The status of this
## goal is set to active upon acceptance, and the status of any
## previously active goal is set to preempted. Preempts received for the
## new goal between checking if isNewGoalAvailable or invokation of a
## goal callback and the acceptNewGoal call will not trigger a preempt
## callback. This means, isPreemptReqauested should be called after
## accepting the goal even for callback-based implementations to make
## sure the new goal does not have a pending preempt request.
## @return A shared_ptr to the new goal.
def accept_new_goal(self):
with self.lock:
if not self.new_goal or not self.next_goal.get_goal():
rospy.logerr(
"Attempting to accept the next goal when a new goal is not available"
)
return None
rospy.logdebug("Accepting a new goal")
#accept the next goal
self.current_goal = self.next_goal
self.new_goal = False
#set preempt to request to equal the preempt state of the new goal
self.preempt_request = self.new_goal_preempt_request
self.new_goal_preempt_request = False
#set the status of the current goal to be active
self.current_goal.set_accepted(
"This goal has been accepted by the queued action server")
return self.current_goal.get_goal()
## @brief Allows polling implementations to query about the availability of a new goal
## @return True if a new goal is available, false otherwise
def is_new_goal_available(self):
return self.new_goal
## @brief Allows polling implementations to query about preempt requests
## @return True if a preempt is requested, false otherwise
def is_preempt_requested(self):
return self.preempt_request
## @brief Allows polling implementations to query about the status of the current goal
## @return True if a goal is active, false otherwise
def is_active(self):
if not self.current_goal.get_goal():
return False
status = self.current_goal.get_goal_status().status
return status == actionlib_msgs.msg.GoalStatus.ACTIVE or status == actionlib_msgs.msg.GoalStatus.PREEMPTING
## @brief Sets the status of the active goal to succeeded
## @param result An optional result to send back to any clients of the goal
def set_succeeded(self, result=None, text=""):
with self.lock:
if not result:
result = self.get_default_result()
self.current_goal.set_succeeded(result, text)
## @brief Sets the status of the active goal to aborted
## @param result An optional result to send back to any clients of the goal
def set_aborted(self, result=None, text=""):
with self.lock:
if not result:
result = self.get_default_result()
self.current_goal.set_aborted(result, text)
## @brief Publishes feedback for a given goal
## @param feedback Shared pointer to the feedback to publish
def publish_feedback(self, feedback):
self.current_goal.publish_feedback(feedback)
def get_default_result(self):
return self.action_server.ActionResultType()
## @brief Sets the status of the active goal to preempted
## @param result An optional result to send back to any clients of the goal
def set_preempted(self, result=None, text=""):
if not result:
result = self.get_default_result()
with self.lock:
rospy.logdebug("Setting the current goal as canceled")
self.current_goal.set_canceled(result, text)
## @brief Allows users to register a callback to be invoked when a new goal is available
## @param cb The callback to be invoked
def register_goal_callback(self, cb):
if self.execute_callback:
rospy.logwarn(
"Cannot call QueuedActionServer.register_goal_callback() because an executeCallback exists. Not going to register it."
)
else:
self.goal_callback = cb
## @brief Allows users to register a callback to be invoked when a new preempt request is available
## @param cb The callback to be invoked
def register_preempt_callback(self, cb):
self.preempt_callback = cb
## @brief Explicitly start the action server, used it auto_start is set to false
def start(self):
self.action_server.start()
## @brief Callback for when the ActionServer receives a new goal and passes it on
def internal_goal_callback(self, goal):
self.execute_condition.acquire()
try:
rospy.logdebug(
"A new goal %shas been recieved by the Queued goal action server",
goal.get_goal_id().id)
if (self.goals_buf.empty()):
self.new_goal = True
self.next_goal = goal
self.goals_buf.put(goal, timeout=1)
else:
self.goals_buf.put(goal, timeout=1)
rospy.loginfo("Queued New Goal")
if self.goal_callback:
self.goal_callback()
#rospy.loginfo("Goals List-----------------------------------------------")
#for item in self.goals_buf:
# rospy.loginfo("Goals Buffer%s" %item.get_goal_status())
#rospy.loginfo("End of the Goals List-------------------------------------")
#if the user has defined a goal callback, we'll call it now
#Trigger runLoop to call execute()
self.execute_condition.notify()
self.execute_condition.release()
except Exception, e:
rospy.logerr(
"QueuedActionServer.internal_goal_callback - exception %s",
str(e))
self.execute_condition.release()
