[python] pprz_msg: minor fixes and move_waypoint_example.py

sw/ground_segment/python/move_waypoint_example.py

@@ -0,0 +1,46 @@
+#!/usr/bin/env python
+
+from __future__ import print_function
+
+import sys
+from os import path, getenv
+
+# if PAPARAZZI_SRC not set, then assume the tree containing this
+# file is a reasonable substitute
+PPRZ_SRC = getenv("PAPARAZZI_SRC", path.normpath(path.join(path.dirname(path.abspath(__file__)), '../../../../')))
+sys.path.append(PPRZ_SRC + "/sw/lib/python")
+
+from ivy_msg_interface import IvyMessagesInterface
+from pprz_msg.message import PprzMessage
+
+class WaypointMover(object):
+    def __init__(self, verbose=False):
+        self.verbose = verbose
+        self._interface = IvyMessagesInterface(self.message_recv)
+
+    def message_recv(self, ac_id, msg):
+        if self.verbose:
+            print("Got msg %s" % msg.name)
+
+    def shutdown(self):
+        print("Shutting down ivy interface...")
+        self._interface.shutdown()
+
+    def __del__(self):
+        self.shutdown()
+
+    def move_waypoint(self, ac_id, wp_id, lat, lon, alt):
+        msg = PprzMessage("ground", "MOVE_WAYPOINT")
+        msg['ac_id'] = ac_id
+        msg['wp_id'] = wp_id
+        msg['lat'] = lat
+        msg['long'] = lon
+        msg['alt'] = alt
+        print("Sending message: %s" % msg)
+        self._interface.send(msg)
+
+
+if __name__ == '__main__':
+    wm = WaypointMover()
+    wm.move_waypoint(ac_id=202, wp_id=3, lat=43.563, lon=1.481, alt=172.0)
+    wm.shutdown()

sw/lib/python/ivy_msg_interface.py

@@ -13,6 +13,7 @@ PPRZ_SRC = os.getenv("PAPARAZZI_SRC", os.path.normpath(os.path.join(os.path.dirn
 sys.path.append(PPRZ_SRC + "/sw/lib/python")
 
 from pprz_msg.message import PprzMessage
+from pprz_msg import messages_xml_map
 
 
 class IvyMessagesInterface(object):
@@ -20,6 +21,8 @@ class IvyMessagesInterface(object):
         self.callback = callback
         self.ivy_id = 0
         self.verbose = verbose
+        # make sure all messages are parsed before we start creating them in callbacks
+        messages_xml_map.parse_messages()
         self.init_ivy(init, bind_regex)
 
     def stop(self):

sw/lib/python/pprz_msg/message.py

@@ -3,12 +3,11 @@ Paparazzi message representation
 
 """
 
-from __future__ import absolute_import, division, print_function
+from __future__ import division, print_function
 import sys
 import json
 import struct
-from . import messages_xml_map
-# import messages_xml_map
+import messages_xml_map
 
 
 class PprzMessageError(Exception):
@@ -118,11 +117,12 @@ class PprzMessage(object):
         self.set_value_by_name(key, value)
 
     def set_values(self, values):
+        #print("msg %s: %s" % (self.name, ", ".join(self.fieldnames)))
         if len(values) == len(self.fieldnames):
             self._fieldvalues = values
         else:
-            print("set values %i %i" % (len(values), len(self.fieldnames)))
-            raise PprzMessageError("Error: fields not matching")
+            raise PprzMessageError("Error: Msg %s has %d fields, tried to set %i values" %
+                                   (self.name, len(self.fieldnames), len(values)))
 
     def set_value_by_name(self, name, value):
         # Try to set a value from its name

sw/lib/python/pprz_msg/messages_xml_map.py

@@ -31,6 +31,7 @@ def parse_messages(messages_file=''):
         messages_file = default_messages_file
     if not os.path.isfile(messages_file):
         raise MessagesNotFound(messages_file)
+    #print("Parsing %s" % messages_file)
     from lxml import etree
     tree = etree.parse(messages_file)
     for the_class in tree.xpath("//msg_class[@name]"):
@@ -152,8 +153,8 @@ def test():
     parse_messages(args.file)
     if args.list_messages:
         print("Listing %i messages in '%s' msg_class" % (len(message_dictionary[args.msg_class]), args.msg_class))
-        for msg in message_dictionary[args.msg_class]:
-            print(msg)
+        for msg_name, msg_fields in message_dictionary[args.msg_class].iteritems():
+            print(msg_name + ": " + ", ".join(msg_fields))
 
 if __name__ == '__main__':
     test()