Modify paramdump to use trigger service

CMakeLists.txt

@@ -7,7 +7,6 @@ project(paramdump)
 find_package(catkin REQUIRED COMPONENTS
   rospy
   std_msgs
-  message_generation
 )
 
 ## System dependencies are found with CMake's conventions
@@ -44,10 +43,9 @@ find_package(catkin REQUIRED COMPONENTS
 ##   * add every package in MSG_DEP_SET to generate_messages(DEPENDENCIES ...)
 
 ## Generate messages in the 'msg' folder
-add_message_files(
-  FILES
-  paramdump.msg
-)
+#add_message_files(
+#  FILES
+#)
 
 ## Generate services in the 'srv' folder
 # add_service_files(
@@ -64,10 +62,10 @@ add_message_files(
 # )
 
 ## Generate added messages and services with any dependencies listed here
-generate_messages(
-  DEPENDENCIES
-  paramdump
-)
+#generate_messages(
+#  DEPENDENCIES
+#  paramdump
+#)
 
 ################################################
 ## Declare ROS dynamic reconfigure parameters ##
@@ -103,7 +101,7 @@ catkin_package(
 #  LIBRARIES paramdump
 #  CATKIN_DEPENDS rospy std_msgs
 #  DEPENDS system_lib
-   CATKIN_DEPENDS message_runtime
+#   CATKIN_DEPENDS message_runtime
 )
 
 ###########

scripts/paramdump.py

@@ -1,34 +1,34 @@
 #!/usr/bin/env python
 
-## Simple program that listens to std_msgs/Strings published 
-## to the 'paramdump' topic.  Upon receiving one that says "dump waypoints", it executes 
-## the rosparam command to dump the waypoint parameters. This allows them to be persistent.
+## Simple program that listens to std_srv/Trigger messages
+## on the /save_waypoints service. Upon receiving one it calles
+## the rosparam command to save the waypoint parameters to a file.
+## Waypoints are currently saved to ~/waypoints.yaml 
 
 import rospy
 import subprocess
-from std_msgs.msg import String
+from std_srvs.srv import Trigger
+from std_srvs.srv import TriggerResponse
 from os.path import expanduser
 
 
-def callback(data):
-    # rospy.loginfo(rospy.get_caller_id() + ' I heard %s', data.data)
+def save_waypoints(req):
+    try: 
+         home = expanduser("~")
+         subprocess.check_output(
+             ["rosparam", "dump", home + "/waypoints.yaml", "/waypoint"],
+             stderr=subprocess.STDOUT
+         )
+         # parameter -v after "dump" will give verbose output
+    except subprocess.CalledProcessError as cpe:
+        return TriggerResponse(False, "Error saving waypoints: %s" % cpe.output)
 
-    if data.data == "dump waypoints":
-        home = expanduser("~")
-        subprocess.call(["rosparam", "dump", home + "/waypoints.yaml", "/waypoint"])
-	# parameter -v after "dump" will give verbose output
-
-def paramdump():
-
-    # rospy.loginfo(rospy.get_caller_id() + 'paramdump is running')
+    return TriggerResponse(True, "")
 
+if __name__ == '__main__':
     rospy.init_node('paramdump')
+    rospy.Service('save_waypoints', Trigger, save_waypoints)
 
-    rospy.Subscriber('paramdump', String, callback)
-
-    # spin() simply keeps python from exiting until this node is stopped
     rospy.spin()
 
-if __name__ == '__main__':
-    paramdump()