acomms/libqueue/queue_xml_callbacks.h

// copyright 2009 t. schneider tes@mit.edu 
//
// this file is part of the Queue Library (libqueue),
// the goby-acomms message queue manager. goby-acomms is a collection of 
// libraries for acoustic underwater networking
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This software is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this software.  If not, see <http://www.gnu.org/licenses/>.

// xml code based initially on work in C++ Cookbook by D. Ryan Stephens, Christopher Diggins, Jonathan Turkanis, and Jeff Cogswell. Copyright 2006 O'Reilly Media, INc., 0-596-00761-2

#ifndef QUEUE_XML_CALLBACKS20091211H
#define QUEUE_XML_CALLBACKS20091211H

#include <stdexcept>
#include <vector>
#include <sstream>

#include <xercesc/sax2/Attributes.hpp>
#include <xercesc/sax2/DefaultHandler.hpp>

#include "goby/protobuf/queue.pb.h"
#include "goby/acomms/xml/xerces_strings.h"
#include "goby/acomms/xml/tags.h"
#include "queue_manager.h"

namespace goby
{
    namespace acomms
    {
    
// Implements callbacks that receive character data and
// notifications about the beginnings and ends of elements 
        class QueueContentHandler : public xercesc::DefaultHandler {
          public:
          QueueContentHandler(std::vector<protobuf::QueueConfig>& q)
              : q_(q)
            { xml::initialize_tags(tags_map_); }
        
            void startElement( 
                const XMLCh *const uri,        // namespace URI
                const XMLCh *const localname,  // tagname w/ out NS prefix
                const XMLCh *const qname,      // tagname + NS pefix
                const xercesc::Attributes &attrs );      // elements's attributes

            void endElement(          
                const XMLCh *const uri,        // namespace URI
                const XMLCh *const localname,  // tagname w/ out NS prefix
                const XMLCh *const qname );     // tagname + NS pefix

#if XERCES_VERSION_MAJOR < 3
            void characters(const XMLCh* const chars, const unsigned int length)
       { current_text.append(toNative(chars), 0, length); }
#else
            void characters(const XMLCh* const chars, const XMLSize_t length )
       { current_text.append(toNative(chars), 0, length); }
#endif
    
          private:
            bool in_message_var()
            { return xml::in_message_var(parents_); }
            bool in_header_var()
            { return xml::in_header_var(parents_); }
            bool in_publish()
            { return xml::in_publish(parents_); }
 
          private:
            std::vector<protobuf::QueueConfig>& q_;
            std::string current_text;
        
            std::set<xml::Tag> parents_;
            std::map<std::string, xml::Tag> tags_map_;
        };

// Receives Error notifications.
        class QueueErrorHandler : public xercesc::DefaultHandler 
        {

          public:
            void warning(const xercesc::SAXParseException& e)
            {
                std::cout << "warning:" << toNative(e.getMessage());
            }
            void error(const xercesc::SAXParseException& e)
            {
                XMLSSize_t line = e.getLineNumber();
                std::stringstream ss;
                ss << "xml parsing error on line " << line << ": " << std::endl << toNative(e.getMessage());
                throw queue_exception(ss.str());
            }
            void fatalError(const xercesc::SAXParseException& e) 
            {
                error(e);
            }
        };
    }
}

#endif