Allow supplying NodeHandle for initParam

Previously, initParam always constructs a default NodeHandle, which
works correctly as long as robot_description param and the node
calling initParam are in the same namespace. This is not true,
when initParam is called via a ros_control controller running in
the global namespace (gazebo), but robot_descriptions still need
to be namespaced. This backwards compatible change allows setting
the NodeHandle.

urdf/include/urdf/model.h

@@ -44,6 +44,7 @@
 #include <tinyxml.h>
 #include <boost/shared_ptr.hpp>
 #include <boost/weak_ptr.hpp>
+#include <ros/ros.h>
 
 namespace urdf{
 
@@ -57,7 +58,7 @@ class Model: public ModelInterface
   /// \brief Load Model given a filename
   bool initFile(const std::string& filename);
   /// \brief Load Model given the name of a parameter on the parameter server
-  bool initParam(const std::string& param);
+  bool initParam(const std::string& param, const ros::NodeHandle& nh = ros::NodeHandle());
   /// \brief Load Model from a XML-string
   bool initString(const std::string& xmlstring);
 };

urdf/src/model.cpp

@@ -36,8 +36,6 @@
 
 #include "urdf/model.h"
 
-#include <ros/ros.h>
-
 /* we include the default parser for plain URDF files; 
    other parsers are loaded via plugins (if available) */
 #include <urdf_parser/urdf_parser.h>
@@ -86,9 +84,8 @@ bool Model::initFile(const std::string& filename)
 }
 
 
-bool Model::initParam(const std::string& param)
+bool Model::initParam(const std::string& param, const ros::NodeHandle& nh)
 {
-  ros::NodeHandle nh;
   std::string xml_string;
 
   // gets the location of the robot description on the parameter server