It appears that in Electric, rospy enforces that strings in ROS messages be
ASCII strings, so the output of the python pickle module can't be encoded.
 to fix this we should be able to just change SmachContainerStatus (
https://kforge.ros.org/smach/executive_smach/file/d79964e4c22f/smach_msgs/msg/SmachContainerStatus.msg)
from:

 12<https://kforge.ros.org/smach/executive_smach/file/d79964e4c22f/smach_msgs/msg/SmachContainerStatus.msg#l12>#
A pickled user data structure
13<https://kforge.ros.org/smach/executive_smach/file/d79964e4c22f/smach_msgs/msg/SmachContainerStatus.msg#l13>string
local_data

to:

 12<https://kforge.ros.org/smach/executive_smach/file/d79964e4c22f/smach_msgs/msg/SmachContainerStatus.msg#l12>#
A pickled user data structure
13<https://kforge.ros.org/smach/executive_smach/file/d79964e4c22f/smach_msgs/msg/SmachContainerStatus.msg#l13>byte[]
local_data

I don't currently have the time to test this, but I'm pretty sure this is
the problem.

-j

On Fri, Oct 28, 2011 at 1:40 PM, Tully Foote <tfoote@willowgarage.com>wrote:

> Hi Manuel,
>
> There's already an open thread on this at
>
> http://answers.ros.org/question/2032/smach-introspection-server-fails-in-electric
>
> Tully
>
> 2011/10/28 Manuel Rodríguez <mrodriguez@robotnik.es>:
> > Hi all,
> >
> > I'm using smach with the introspection server and the smach_viewer.py
> > but does not work fine (it just shows the machine but does not update in
> > which state the machine is), moreover the script running the
> introspection
> > server periodically shows the following exception:
> >>
> >> Traceback (most recent call last):
> >>   File "/usr/lib/python2.6/threading.py", line 532, in __bootstrap_inner
> >>     self.run()
> >>   File "/usr/lib/python2.6/threading.py", line 484, in run
> >>     self.__target(*self.__args, **self.__kwargs)
> >>   File
> >>
> "/opt/ros/electric/stacks/executive_smach/smach_ros/src/smach_ros/introspection.py",
> >> line 160, in _status_pub_loop
> >>     self._publish_status('HEARTBEAT')
> >>   File
> >>
> "/opt/ros/electric/stacks/executive_smach/smach_ros/src/smach_ros/introspection.py",
> >> line 225, in _publish_status
> >>     self._status_pub.publish(state_msg)
> >>   File
> >> "/opt/ros/electric/stacks/ros_comm/clients/rospy/src/rospy/topics.py",
> line
> >> 695, in publish
> >>     self.impl.publish(data)
> >>   File
> >> "/opt/ros/electric/stacks/ros_comm/clients/rospy/src/rospy/topics.py",
> line
> >> 872, in publish
> >>     serialize_message(b, self.seq, message)
> >>   File
> "/opt/ros/electric/stacks/ros_comm/clients/rospy/src/rospy/msg.py",
> >> line 151, in serialize_message
> >>     msg.serialize(b)
> >>   File
> >>
> "/opt/ros/electric/stacks/executive_smach/smach_msgs/src/smach_msgs/msg/_SmachContainerStatus.py",
> >> line 120, in serialize
> >>     buff.write(struct.pack('<I%ss'%length, length, _x.encode()))
> >> UnicodeDecodeError: 'ascii' codec can't decode byte 0x80 in position 0:
> >> ordinal not in range(128)
> >
> > Has anyone knows how to solve this trouble?
> > Best regards,
> > Manuel
> >
> > _______________________________________________
> > ros-users mailing list
> > ros-users@code.ros.org
> > https://code.ros.org/mailman/listinfo/ros-users
> >
> >
>
>
>
> --
> Tully Foote
> Systems Engineer
> Willow Garage, Inc.
> tfoote@willowgarage.com
> (650) 475-2827
> _______________________________________________
> ros-users mailing list
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>