Merge pull request #55 from sgemme-csa/master

KeyError in publishCameraState when camera is not ready on PTZ camera

nodes/axis_ptz.py

@@ -35,8 +35,9 @@ def run(self):
     def queryCameraPosition(self):
         '''Using Axis VAPIX protocol, described in the comments at the top of
         this file, is used to query the state of the camera'''
-        conn = httplib.HTTPConnection(self.axis.hostname)
         queryParams = { 'query':'position' }
+        conn = httplib.HTTPConnection(self.axis.hostname)
+
         try:
             conn.request("GET", "/axis-cgi/com/ptz.cgi?%s" % 
                                                 urllib.urlencode(queryParams))
@@ -69,21 +70,24 @@ def queryCameraPosition(self):
 
     def publishCameraState(self):
         '''Publish camera state to a ROS message'''
-        if self.cameraPosition is not None:
-            self.msg.pan = float(self.cameraPosition['pan'])
-            if self.axis.flip:
-                self.adjustForFlippedOrientation()
-            self.msg.tilt = float(self.cameraPosition['tilt'])
-            self.msg.zoom = float(self.cameraPosition['zoom'])
-            self.msg.iris = 0.0
-            if 'iris' in self.cameraPosition:
-                self.msg.iris = float(self.cameraPosition['iris'])
-            self.msg.focus = 0.0
-            if 'focus' in self.cameraPosition:
-                self.msg.focus = float(self.cameraPosition['focus'])
-            if 'autofocus' in self.cameraPosition:
-                self.msg.autofocus = (self.cameraPosition['autofocus'] == 'on')
-            self.axis.pub.publish(self.msg)
+        try:
+            if self.cameraPosition is not None:
+                self.msg.pan = float(self.cameraPosition['pan'])
+                if self.axis.flip:
+                    self.adjustForFlippedOrientation()
+                self.msg.tilt = float(self.cameraPosition['tilt'])
+                self.msg.zoom = float(self.cameraPosition['zoom'])
+                self.msg.iris = 0.0
+                if 'iris' in self.cameraPosition:
+                    self.msg.iris = float(self.cameraPosition['iris'])
+                self.msg.focus = 0.0
+                if 'focus' in self.cameraPosition:
+                    self.msg.focus = float(self.cameraPosition['focus'])
+                if 'autofocus' in self.cameraPosition:
+                    self.msg.autofocus = (self.cameraPosition['autofocus'] == 'on')
+                self.axis.pub.publish(self.msg)
+        except KeyError as e:
+            rospy.logwarn("Camera not ready for polling its telemetry: " + repr(e.message))
 
     def adjustForFlippedOrientation(self):
         '''Correct pan and tilt parameters if camera is mounted backwards and 
@@ -303,4 +307,4 @@ def main():
 
 if __name__ == "__main__":
     main()
-
+