source: main/tags/2.10/gsdl/src/colservr/mggdbmsource.cpp@ 32704

/**********************************************************************
 *
 * mggdbmsource.cpp -- 
 * Copyright (C) 1999  The New Zealand Digital Library Project
 *
 * A component of the Greenstone digital library software
 * from the New Zealand Digital Library Project at the
 * University of Waikato, New Zealand.
 *
 * 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 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * $Id: mggdbmsource.cpp 650 1999-10-10 08:20:37Z sjboddie $
 *
 *********************************************************************/

/*
   $Log$
   Revision 1.16  1999/10/10 08:20:36  sjboddie
   - metadata now returns map rather than array
   - redesigned browsing support (although it's not finished so
   won't currently work ;-)

   Revision 1.15  1999/09/07 04:57:22  sjboddie
   added gpl notice

   Revision 1.14  1999/08/31 22:40:44  rjmcnab
   A couple of gdbm changes.

   Revision 1.13  1999/08/13 04:20:27  sjboddie
   added ability to get return all available metadata when 'fields' is empty

   Revision 1.12  1999/07/07 06:17:47  rjmcnab
   broke search_index into index+subcollection+language
   within mgsearch

   Revision 1.11  1999/07/01 03:49:54  rjmcnab
   fixed a small warning.

   Revision 1.10  1999/06/29 23:06:07  sjboddie
   Fixed up default index for get_document

   Revision 1.9  1999/06/16 02:00:34  sjboddie
   Few changes to get getParent filter option to return metadata of
   parents as well as current OID

   Revision 1.8  1999/05/10 03:43:48  sjboddie
   lots of changes to lots of files - getting document action going

   Revision 1.7  1999/04/30 02:00:47  sjboddie
   lots of stuff to do with getting documentaction working

   Revision 1.6  1999/04/21 22:40:44  sjboddie
   made another change to the one I just committed. if requested metadata doesn't
   exist it now puts an empty string in the response array so we don't always
   have to test that a value exists before using it.

   Revision 1.5  1999/04/21 05:23:46  sjboddie

   changed the way metadata is returned

   Revision 1.4  1999/04/19 23:56:07  rjmcnab
   Finished the gdbm metadata stuff

   Revision 1.3  1999/04/12 10:30:33  rjmcnab
   Made a little more progress.

   Revision 1.2  1999/04/12 05:21:51  rjmcnab
   Started on a mg and gdbm source.

   Revision 1.1  1999/04/12 03:40:40  rjmcnab
   Initial revision.

 */


#include "mggdbmsource.h"
#include "fileutil.h"
#include "OIDtools.h"


mggdbmsourceclass::mggdbmsourceclass () {
  gdbmptr = NULL;
  mgsearchptr = NULL;
}

mggdbmsourceclass::~mggdbmsourceclass () {
}

void mggdbmsourceclass::configure (const text_t &key, const text_tarray &cfgline) {
  if (cfgline.size() >= 1) {
    const text_t &value = cfgline[0];

    if (key == "collection") collection = value;
    else if (key == "collectdir") collectdir = value;
    else if (key == "gsdlhome") gsdlhome = value;
  }

  if (key == "indexmap") {
    indexmap.importmap (cfgline);

  } else if (key == "defaultindex") {
    indexmap.from2to (cfgline[0], defaultindex);

  } else if (key == "subcollectionmap") {
    subcollectionmap.importmap (cfgline);

  } else if (key == "defaultsubcollection") {
    subcollectionmap.from2to (cfgline[0], defaultsubcollection);

  } else if (key == "languagemap") {
    languagemap.importmap (cfgline);

  } else if (key == "defaultlanguage") 
    languagemap.from2to (cfgline[0], defaultlanguage);
}

bool mggdbmsourceclass::init (ostream &logout) {
  outconvertclass text_t2ascii;
  
  if (!sourceclass::init (logout)) return false;
  
  // get the collection directory name
  if (collectdir.empty()) {
    collectdir = filename_cat (gsdlhome, "collect", collection);
  }
  
  // get the filename for the database and make sure it exists
  gdbm_filename = filename_cat(collectdir,"index","text",collection);

#ifdef _LITTLE_ENDIAN
  gdbm_filename += ".ldb";
#else
  gdbm_filename += ".bdb";
#endif
  if (!file_exists(gdbm_filename)) {
    logout << text_t2ascii
       << "error: gdbm database \""
       << gdbm_filename << "\" does not exist\n\n";
    return false;
  }
  
  return true;
}

bool mggdbmsourceclass::translate_OID (const text_t &OIDin, text_t &OIDout, 
                       comerror_t &err, ostream &logout) {

  outconvertclass text_t2ascii;

  err = noError;
  if (gdbmptr == NULL) {
    // most likely a configuration problem
    logout << text_t2ascii 
       << "configuration error: mggdbmsource contains a null gdbmclass\n\n";
    err = configurationError;
    return true;
  }

  // open the database
  gdbmptr->setlogout(&logout);
  if (!gdbmptr->opendatabase (gdbm_filename, GDBM_READER, 100, false)) {
    // most likely a system problem (we have already checked that the
    // gdbm database exists)
    logout << text_t2ascii
       << "system problem: open on gdbm database \""
       << gdbm_filename << "\" failed\n\n";
    err = systemProblem;
    return true;
  }

  infodbclass info;
  OIDout = gdbmptr->translate_OID (OIDin, info);
  return true;
}

bool mggdbmsourceclass::get_metadata (const text_t &/*requestParams*/, const text_t &/*refParams*/, 
                      bool getParents, const text_tset &fields, 
                      const text_t &OID, MetadataInfo_tmap &metadata, 
                      comerror_t &err, ostream &logout) {
  outconvertclass text_t2ascii;

  metadata.erase(metadata.begin(), metadata.end());

  err = noError;
  if (gdbmptr == NULL) {
    // most likely a configuration problem
    logout << text_t2ascii 
       << "configuration error: mggdbmsource contains a null gdbmclass\n\n";
    err = configurationError;
    return true;
  }

  // open the database
  gdbmptr->setlogout(&logout);
  if (!gdbmptr->opendatabase (gdbm_filename, GDBM_READER, 100, false)) {
    // most likely a system problem (we have already checked that the
    // gdbm database exists)
    logout << text_t2ascii
       << "system problem: open on gdbm database \""
       << gdbm_filename << "\" failed\n\n";
    err = systemProblem;
    return true;
  }

  // get the metadata - if getParents is set we need to get 
  // info for all parents of OID as well as OID
  vector<infodbclass> info_array;
  text_tarray OIDs;
  if (getParents) get_parents_array (OID, OIDs);
  OIDs.push_back (OID);

  text_tarray::const_iterator this_OID = OIDs.begin();
  text_tarray::const_iterator end_OID = OIDs.end();

  while (this_OID != end_OID) {
    infodbclass info;
    if (!gdbmptr->getinfo(*this_OID, info)) return false;

    // adjust the metadata
    text_t &contains = info["contains"];
    if (contains.empty()) info["haschildren"] = 0;
    else info["haschildren"] = 1;
    contains.clear();

    info_array.push_back(info);
    this_OID ++;
  }

  // if fields set is empty we want to get all available metadata
  text_tset tfields = fields;
  if (tfields.empty() && !info_array.empty()) {
    infodbclass::iterator t_info = info_array[0].begin(); 
    infodbclass::iterator e_info = info_array[0].end(); 
    while (t_info != e_info) {
      if ((*t_info).first != "contains")
    tfields.insert ((*t_info).first);
      t_info ++;
    }
    tfields.insert ("hasnext");
    tfields.insert ("hasprevious");
  }
    
  // collect together the metadata
  bool donenextprevtest = false;
  bool hasnext=false, hasprevious=false;
  MetadataInfo_t this_metadata;
  text_tarray *pos_metadata;
  text_tset::const_iterator fields_here = tfields.begin();
  text_tset::const_iterator fields_end = tfields.end();
  while (fields_here != fields_end) {
    this_metadata.clear();
    this_metadata.isRef = false;

    vector<infodbclass>::reverse_iterator this_info = info_array.rbegin(); 
    vector<infodbclass>::reverse_iterator end_info = info_array.rend(); 
    MetadataInfo_t *tmetaptr = &this_metadata;
    while (this_info != end_info) {

      pos_metadata = (*this_info).getmultinfo(*fields_here);
    
      if ((*fields_here == "hasnext" || *fields_here == "hasprevious")) {
    
    // collect metadata
    if (!donenextprevtest) {
      donenextprevtest = true;
      
      // cache parent contents array
      text_t thisparent = get_parent (OID);
      if (thisparent != parentOID) {
        parentOID = thisparent;
        parentcontents.erase(parentcontents.begin(), parentcontents.end());
        if (gdbmptr->getinfo(parentOID, parentinfo)) {
          text_t &parentinfocontains = parentinfo["contains"];
          if (!parentinfocontains.empty())
        splitchar (parentinfocontains.begin(), parentinfocontains.end(), 
               ';', parentcontents);
        }
      }
      
      // do tests
      text_tarray::const_iterator parentcontents_here = parentcontents.begin();
      text_tarray::const_iterator parentcontents_end = parentcontents.end();
      text_t shrunk_OID = OID;
      shrink_parent (shrunk_OID);
      while (parentcontents_here != parentcontents_end) {
        if (*parentcontents_here == shrunk_OID) {
          if (parentcontents_here == parentcontents.begin()) hasprevious = false;
          else hasprevious = true;
          
          parentcontents_here++;
          
          if (parentcontents_here == parentcontents.end()) hasnext = false;
          else hasnext = true;
          
          break;
        }  
        
        parentcontents_here ++;
      }
    }  
    
    // fill in metadata
    if ((*fields_here == "hasnext" && hasnext) ||
        (*fields_here == "hasprevious" && hasprevious))
      tmetaptr->values.push_back("1");
    else
      tmetaptr->values.push_back("0");
    
      }
      else if (pos_metadata != NULL && *fields_here != "contains")
    tmetaptr->values = *pos_metadata;
      else
    tmetaptr->values.push_back("");

      this_info ++;
      if (this_info != end_info) {
    tmetaptr->parent = new MetadataInfo_t();
    tmetaptr = tmetaptr->parent;
      }
    }
    metadata[*fields_here] = this_metadata;
    
    fields_here++;
  }

  return true;
}


bool mggdbmsourceclass::get_document (const text_t &OID, text_t &doc, 
                      comerror_t &err, ostream &logout) {

  outconvertclass text_t2ascii;

  err = noError;
  if (gdbmptr == NULL) {
    // most likely a configuration problem
    logout << text_t2ascii 
       << "configuration error: mggdbmsource contains a null gdbmclass\n\n";
    err = configurationError;
    return true;
  }

  // open the database
  gdbmptr->setlogout(&logout);
  if (!gdbmptr->opendatabase (gdbm_filename, GDBM_READER, 100, false)) {
    // most likely a system problem (we have already checked that the
    // gdbm database exists)
    logout << text_t2ascii
       << "system problem: open on gdbm database \""
       << gdbm_filename << "\" failed\n\n";
    err = systemProblem;
    return true;
  }

  text_t tOID = OID;
  if (needs_translating (OID)) 
    translate_OID (OID, tOID, err, logout);
  infodbclass info;
  if (!gdbmptr->getinfo(tOID, info)) return false;
  
  if (info["hastxt"].getint() == 1) {
    int docnum = info["docnum"].getint();
    
    // set the collection directory
    mgsearchptr->setcollectdir (collectdir);
    
    // get the text
    mgsearchptr->docTargetDocument(defaultindex, defaultsubcollection,
                   defaultlanguage, collection, docnum, doc);
  }
  return true;
}