DDSLoader.h

// This file is part of the "NcML Module" project, a BES module designed
// to allow NcML files to be used to be used as a wrapper to add
// AIS to existing datasets of any format.
//
// Copyright (c) 2009 OPeNDAP, Inc.
// Author: Michael Johnson  <m.johnson@opendap.org>
//
// For more information, please also see the main website: http://opendap.org/
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library 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
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
//
// Please see the files COPYING and COPYRIGHT for more information on the GLPL.
//
// You can contact OPeNDAP, Inc. at PO Box 112, Saunderstown, RI. 02874-0112.
#ifndef __NCML_MODULE_DDSLOADER_H__
#define __NCML_MODULE_DDSLOADER_H__
 
#include <memory>
#include <string>
 
class BESDataHandlerInterface;
class BESContainer;
class BESContainerStorage;
class BESDapResponse;
class BESResponseObject;
 
namespace agg_util {
 
class DDSLoader {
private:
    // The dhi to use for the loading, passed in on creation.
    // Rep Invariant: the dhi state is the same on call exits as it was on call entry.
    BESDataHandlerInterface& _dhi;
 
    // whether we have actually hijacked the dhi, so restore knows.
    bool _hijacked;
 
    // The file we are laoding if we're hijacked
    std::string _filename;
 
    // Remember the store so we can pull the location out in restoreDHI on exception as well.
    BESContainerStorage* _store;
 
    // DHI state we hijack, for putting back on exception.
    std::string _containerSymbol;
    std::string _origAction;
    std::string _origActionName;
    BESContainer* _origContainer;
    BESResponseObject* _origResponse;
 
    // A counter we use to generate a "class-unique" symbol for containers internally.
    // Incremented by getNextContainerName().
    static long _gensymID;
 
public:
 
    enum ResponseType {
        eRT_RequestDDX = 0, eRT_RequestDataDDS // Not used. jhrg 3/31/22 eRT_Num
    };
 
    explicit DDSLoader(BESDataHandlerInterface &dhi);
 
    DDSLoader(const DDSLoader& proto);
    DDSLoader& operator=(const DDSLoader&);
 
    virtual ~DDSLoader();
 
    BESDataHandlerInterface& getDHI() const
    {
        return _dhi;
    }
 
#if 0
    std::unique_ptr<BESDapResponse> load(const std::string& location, ResponseType type);
#endif
 
    void loadInto(const std::string& location, ResponseType type, BESDapResponse* pResponse);
 
    void cleanup();
 
 
    static std::unique_ptr<BESDapResponse> makeResponseForType(ResponseType type);
 
    static std::string getActionForType(ResponseType type);
 
    static std::string getActionNameForType(ResponseType type);
 
    static bool checkResponseIsValidType(ResponseType type, BESDapResponse* pResponse);
 
private:
 
    void snapshotDHI();
 
    void restoreDHI();
 
    BESContainer* addNewContainerToStorage();
 
    void removeContainerFromStorage();
 
    void ensureClean();
 
    static std::string getNextContainerName();
 
};
// class DDSLoader
}// namespace ncml_module
 
#endif /* __NCML_MODULE_DDSLOADER_H__ */