src/filter_record_transform.cpp

   1 /* This file is part of Metaproxy.
   2    Copyright (C) 2005-2011 Index Data
   3
   4 Metaproxy is free software; you can redistribute it and/or modify it under
   5 the terms of the GNU General Public License as published by the Free
   6 Software Foundation; either version 2, or (at your option) any later
   7 version.
   8
   9 Metaproxy is distributed in the hope that it will be useful, but WITHOUT ANY
  10 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12 for more details.
  13
  14 You should have received a copy of the GNU General Public License
  15 along with this program; if not, write to the Free Software
  16 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17 */
  18
  19 #include "config.hpp"
  20 #include "filter_record_transform.hpp"
  21 #include <metaproxy/package.hpp>
  22 #include <metaproxy/util.hpp>
  23 #include "gduutil.hpp"
  24
  25 #include <yaz/diagbib1.h>
  26 #include <yaz/zgdu.h>
  27 #include <yaz/retrieval.h>
  28
  29 #include <iostream>
  30
  31 namespace mp = metaproxy_1;
  32 namespace yf = mp::filter;
  33 namespace mp_util = metaproxy_1::util;
  34
  35 namespace metaproxy_1 {
  36     namespace filter {
  37         class RecordTransform::Impl {
  38         public:
  39             Impl();
  40             ~Impl();
  41             void process(metaproxy_1::Package & package) const;
  42             void configure(const xmlNode * xml_node);
  43         private:
  44             yaz_retrieval_t m_retrieval;
  45         };
  46     }
  47 }
  48
  49 // define Pimpl wrapper forwarding to Impl
  50
  51 yf::RecordTransform::RecordTransform() : m_p(new Impl)
  52 {
  53 }
  54
  55 yf::RecordTransform::~RecordTransform()
  56 {  // must have a destructor because of boost::scoped_ptr
  57 }
  58
  59 void yf::RecordTransform::configure(const xmlNode *xmlnode, bool test_only,
  60                                     const char *path)
  61 {
  62     m_p->configure(xmlnode);
  63 }
  64
  65 void yf::RecordTransform::process(mp::Package &package) const
  66 {
  67     m_p->process(package);
  68 }
  69
  70
  71 // define Implementation stuff
  72
  73
  74
  75 yf::RecordTransform::Impl::Impl()
  76 {
  77     m_retrieval = yaz_retrieval_create();
  78     assert(m_retrieval);
  79 }
  80
  81 yf::RecordTransform::Impl::~Impl()
  82 {
  83     if (m_retrieval)
  84         yaz_retrieval_destroy(m_retrieval);
  85 }
  86
  87 void yf::RecordTransform::Impl::configure(const xmlNode *xml_node)
  88 {
  89     //const char *srcdir = getenv("srcdir");
  90     //if (srcdir)
  91     //    yaz_retrieval_set_path(m_retrieval, srcdir);
  92
  93     if (!xml_node)
  94         throw mp::XMLError("RecordTransform filter config: empty XML DOM");
  95
  96     // parsing down to retrieval node, which can be any of the children nodes
  97     xmlNode *retrieval_node;
  98     for (retrieval_node = xml_node->children;
  99          retrieval_node;
 100          retrieval_node = retrieval_node->next)
 101     {
 102         if (retrieval_node->type != XML_ELEMENT_NODE)
 103             continue;
 104         if (0 == strcmp((const char *) retrieval_node->name, "retrievalinfo"))
 105             break;
 106     }
 107
 108     // read configuration
 109     if ( 0 != yaz_retrieval_configure(m_retrieval, retrieval_node)){
 110         std::string msg("RecordTransform filter config: ");
 111         msg += yaz_retrieval_get_error(m_retrieval);
 112         throw mp::XMLError(msg);
 113     }
 114 }
 115
 116 void yf::RecordTransform::Impl::process(mp::Package &package) const
 117 {
 118
 119     Z_GDU *gdu_req = package.request().get();
 120
 121     // only working on z3950 present packages
 122     if (!gdu_req
 123         || !(gdu_req->which == Z_GDU_Z3950)
 124         || !(gdu_req->u.z3950->which == Z_APDU_presentRequest))
 125     {
 126         package.move();
 127         return;
 128     }
 129
 130     // getting original present request
 131     Z_PresentRequest *pr_req = gdu_req->u.z3950->u.presentRequest;
 132
 133     // setting up ODR's for memory during encoding/decoding
 134     //mp::odr odr_de(ODR_DECODE);
 135     mp::odr odr_en(ODR_ENCODE);
 136
 137     // setting up variables for conversion state
 138     yaz_record_conv_t rc = 0;
 139     int ret_code;
 140
 141     const char *input_schema = 0;
 142     Odr_oid *input_syntax = 0;
 143
 144     if(pr_req->recordComposition){
 145         input_schema
 146             = mp_util::record_composition_to_esn(pr_req->recordComposition);
 147     }
 148     if(pr_req->preferredRecordSyntax){
 149         input_syntax = pr_req->preferredRecordSyntax;
 150     }
 151
 152     const char *match_schema = 0;
 153     Odr_oid *match_syntax = 0;
 154
 155     const char *backend_schema = 0;
 156     Odr_oid *backend_syntax = 0;
 157
 158     ret_code
 159         = yaz_retrieval_request(m_retrieval,
 160                                 input_schema, input_syntax,
 161                                 &match_schema, &match_syntax,
 162                                 &rc,
 163                                 &backend_schema, &backend_syntax);
 164
 165     // error handling
 166     if (ret_code != 0)
 167     {
 168         // need to construct present error package and send back
 169
 170         Z_APDU *apdu = 0;
 171
 172         const char *details = 0;
 173         if (ret_code == -1) /* error ? */
 174         {
 175            details = yaz_retrieval_get_error(m_retrieval);
 176            apdu = odr_en.create_presentResponse(
 177                gdu_req->u.z3950,
 178                YAZ_BIB1_SYSTEM_ERROR_IN_PRESENTING_RECORDS, details);
 179         }
 180         else if (ret_code == 1 || ret_code == 3)
 181         {
 182             details = input_schema;
 183             apdu = odr_en.create_presentResponse(
 184                 gdu_req->u.z3950,
 185                 YAZ_BIB1_ELEMENT_SET_NAMES_UNSUPP, details);
 186         }
 187         else if (ret_code == 2)
 188         {
 189             char oidbuf[OID_STR_MAX];
 190             oid_oid_to_dotstring(input_syntax, oidbuf);
 191             details = odr_strdup(odr_en, oidbuf);
 192
 193             apdu = odr_en.create_presentResponse(
 194                 gdu_req->u.z3950,
 195                 YAZ_BIB1_RECORD_SYNTAX_UNSUPP, details);
 196         }
 197         package.response() = apdu;
 198         return;
 199     }
 200
 201     // now re-coding the z3950 backend present request
 202
 203     if (backend_syntax)
 204         pr_req->preferredRecordSyntax = odr_oiddup(odr_en, backend_syntax);
 205     else
 206         pr_req->preferredRecordSyntax = 0;
 207
 208
 209     // z3950'fy record schema
 210     if (backend_schema)
 211     {
 212         pr_req->recordComposition
 213             = (Z_RecordComposition *)
 214               odr_malloc(odr_en, sizeof(Z_RecordComposition));
 215         pr_req->recordComposition->which
 216             = Z_RecordComp_simple;
 217         pr_req->recordComposition->u.simple
 218             = (Z_ElementSetNames *)
 219                odr_malloc(odr_en, sizeof(Z_ElementSetNames));
 220         pr_req->recordComposition->u.simple->which = Z_ElementSetNames_generic;
 221         pr_req->recordComposition->u.simple->u.generic
 222             = odr_strdup(odr_en, backend_schema);
 223     }
 224
 225     // attaching Z3950 package to filter chain
 226     package.request() = gdu_req;
 227
 228     package.move();
 229
 230    //check successful Z3950 present response
 231     Z_GDU *gdu_res = package.response().get();
 232     if (!gdu_res || gdu_res->which != Z_GDU_Z3950
 233         || gdu_res->u.z3950->which != Z_APDU_presentResponse
 234         || !gdu_res->u.z3950->u.presentResponse)
 235
 236     {
 237         package.session().close();
 238         return;
 239     }
 240
 241
 242     // everything fine, continuing
 243     // std::cout << "z3950_present_request OK\n";
 244     // std::cout << "back z3950 " << *gdu_res << "\n";
 245
 246     Z_PresentResponse * pr_res = gdu_res->u.z3950->u.presentResponse;
 247
 248     // let non surrogate dioagnostics in Z3950 present response package
 249     // pass to frontend - just return
 250     if (pr_res->records
 251         && pr_res->records->which == Z_Records_NSD
 252         && pr_res->records->u.nonSurrogateDiagnostic)
 253     {
 254         // we might do more clever tricks to "reverse"
 255         // these error(s).
 256
 257         //*pr_res->records->u.nonSurrogateDiagnostic->condition =
 258         // YAZ_BIB1_SYSTEM_ERROR_IN_PRESENTING_RECORDS;
 259     }
 260
 261     // record transformation must take place
 262     if (rc && pr_res
 263         && pr_res->numberOfRecordsReturned
 264         && *(pr_res->numberOfRecordsReturned) > 0
 265         && pr_res->records
 266         && pr_res->records->which == Z_Records_DBOSD
 267         && pr_res->records->u.databaseOrSurDiagnostics->num_records)
 268     {
 269          //transform all records
 270          for (int i = 0;
 271               i < pr_res->records->u.databaseOrSurDiagnostics->num_records;
 272               i++)
 273          {
 274              Z_NamePlusRecord *npr
 275                  = pr_res->records->u.databaseOrSurDiagnostics->records[i];
 276              if (npr->which == Z_NamePlusRecord_databaseRecord)
 277              {
 278                  WRBUF output_record = wrbuf_alloc();
 279                  Z_External *r = npr->u.databaseRecord;
 280                  int ret_trans = 0;
 281                  if (r->which == Z_External_OPAC)
 282                  {
 283 #if YAZ_VERSIONL >= 0x030011
 284                      ret_trans =
 285                          yaz_record_conv_opac_record(rc, r->u.opac,
 286                                                      output_record);
 287 #else
 288                      ;
 289 #endif
 290                  }
 291                  else if (r->which == Z_External_octet)
 292                  {
 293                      ret_trans =
 294                          yaz_record_conv_record(rc, (const char *)
 295                                                 r->u.octet_aligned->buf,
 296                                                 r->u.octet_aligned->len,
 297                                                 output_record);
 298                  }
 299                  if (ret_trans == 0)
 300                  {
 301                      npr->u.databaseRecord =
 302                          z_ext_record_oid(odr_en, match_syntax,
 303                                           wrbuf_buf(output_record),
 304                                           wrbuf_len(output_record));
 305                  }
 306                  else
 307                  {
 308                      pr_res->records->
 309                          u.databaseOrSurDiagnostics->records[i]
 310                          =  zget_surrogateDiagRec(
 311                              odr_en, npr->databaseName,
 312                              YAZ_BIB1_SYSTEM_ERROR_IN_PRESENTING_RECORDS,
 313                              yaz_record_conv_get_error(rc));
 314                  }
 315                  wrbuf_destroy(output_record);
 316              }
 317          }
 318     }
 319     package.response() = gdu_res;
 320     return;
 321 }
 322
 323
 324 static mp::filter::Base* filter_creator()
 325 {
 326     return new mp::filter::RecordTransform;
 327 }
 328
 329 extern "C" {
 330     struct metaproxy_1_filter_struct metaproxy_1_filter_record_transform = {
 331         0,
 332         "record_transform",
 333         filter_creator
 334     };
 335 }
 336
 337
 338 /*
 339  * Local variables:
 340  * c-basic-offset: 4
 341  * c-file-style: "Stroustrup"
 342  * indent-tabs-mode: nil
 343  * End:
 344  * vim: shiftwidth=4 tabstop=8 expandtab
 345  */
 346