src/filter_virt_db.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
  21 #include "filter_virt_db.hpp"
  22 #include <metaproxy/package.hpp>
  23
  24 #include <boost/thread/mutex.hpp>
  25 #include <boost/thread/condition.hpp>
  26 #include <boost/shared_ptr.hpp>
  27
  28 #include <metaproxy/util.hpp>
  29 #include "torus.hpp"
  30
  31 #include <yaz/zgdu.h>
  32 #include <yaz/otherinfo.h>
  33 #include <yaz/diagbib1.h>
  34 #include <yaz/match_glob.h>
  35 #include <yaz/query-charset.h>
  36 #include <yaz/log.h>
  37
  38 #include <map>
  39 #include <iostream>
  40
  41 namespace mp = metaproxy_1;
  42 namespace yf = mp::filter;
  43
  44 namespace metaproxy_1 {
  45     namespace filter {
  46
  47         struct VirtualDB::Set {
  48             Set(BackendPtr b, std::string setname);
  49             Set();
  50             ~Set();
  51
  52             BackendPtr m_backend;
  53             std::string m_setname;
  54         };
  55         struct VirtualDB::Map {
  56             Map(std::string database, std::list<std::string> targets, std::string route);
  57             Map(std::string database, std::string target, std::string route);
  58             Map();
  59             bool match(const std::string db) const;
  60             std::string m_dbpattern;
  61             std::list<std::string> m_targets;
  62             std::string m_route;
  63         public:
  64             std::string query_encoding;
  65         };
  66         struct VirtualDB::Backend {
  67             mp::Session m_backend_session;
  68             std::list<std::string> m_frontend_databases;
  69             std::list<std::string> m_targets;
  70             std::string m_route;
  71             std::string query_encoding;
  72             bool m_named_result_sets;
  73             int m_number_of_sets;
  74         };
  75         struct VirtualDB::Frontend {
  76             Frontend(Rep *rep);
  77             ~Frontend();
  78             mp::Session m_session;
  79             bool m_is_virtual;
  80             bool m_in_use;
  81             yazpp_1::GDU m_init_gdu;
  82             std::list<BackendPtr> m_backend_list;
  83             std::map<std::string,VirtualDB::Set> m_sets;
  84
  85             void search(Package &package, Z_APDU *apdu);
  86             void present(Package &package, Z_APDU *apdu);
  87             void scan(Package &package, Z_APDU *apdu);
  88             int relay_apdu(Package &package, Z_APDU *apdu);
  89
  90             void close(Package &package);
  91             typedef std::map<std::string,VirtualDB::Set>::iterator Sets_it;
  92
  93             void fixup_package(Package &p, BackendPtr b);
  94             void fixup_npr_record(ODR odr, Z_NamePlusRecord *npr,
  95                                   BackendPtr b);
  96             void fixup_npr_records(ODR odr, Z_Records *records,
  97                                    BackendPtr b);
  98
  99             BackendPtr lookup_backend_from_databases(
 100                 std::list<std::string> databases);
 101             BackendPtr create_backend_from_databases(
 102                 std::list<std::string> databases,
 103                 int &error_code,
 104                 std::string &failing_database);
 105
 106             BackendPtr init_backend(std::list<std::string> database,
 107                                     Package &package,
 108                                     int &error_code, std::string &addinfo);
 109             Rep *m_p;
 110         };
 111         class VirtualDB::Rep {
 112             friend class VirtualDB;
 113             friend struct Frontend;
 114
 115             FrontendPtr get_frontend(Package &package);
 116             void release_frontend(Package &package);
 117             void refresh_torus();
 118         private:
 119             std::list<VirtualDB::Map>m_maps;
 120             typedef std::map<std::string,VirtualDB::Set>::iterator Sets_it;
 121             boost::mutex m_mutex;
 122             boost::condition m_cond_session_ready;
 123             std::map<mp::Session, FrontendPtr> m_clients;
 124             bool pass_vhosts;
 125         };
 126     }
 127 }
 128
 129 yf::VirtualDB::BackendPtr yf::VirtualDB::Frontend::lookup_backend_from_databases(
 130     std::list<std::string> databases)
 131 {
 132     std::list<BackendPtr>::const_iterator map_it;
 133     map_it = m_backend_list.begin();
 134     for (; map_it != m_backend_list.end(); map_it++)
 135         if ((*map_it)->m_frontend_databases == databases)
 136             return *map_it;
 137     BackendPtr null;
 138     return null;
 139 }
 140
 141 yf::VirtualDB::BackendPtr yf::VirtualDB::Frontend::create_backend_from_databases(
 142     std::list<std::string> databases, int &error_code, std::string &addinfo)
 143 {
 144     BackendPtr b(new Backend);
 145     std::list<std::string>::const_iterator db_it = databases.begin();
 146
 147     b->m_number_of_sets = 0;
 148     b->m_frontend_databases = databases;
 149     b->m_named_result_sets = false;
 150
 151     bool first_route = true;
 152
 153     std::map<std::string,bool> targets_dedup;
 154     for (; db_it != databases.end(); db_it++)
 155     {
 156         std::list<VirtualDB::Map>::const_iterator map_it;
 157         map_it = m_p->m_maps.begin();
 158         while (map_it != m_p->m_maps.end())
 159         {
 160             if (map_it->match(*db_it))
 161                 break;
 162             map_it++;
 163         }
 164
 165         if (map_it == m_p->m_maps.end())  // database not found
 166         {
 167             error_code = YAZ_BIB1_DATABASE_DOES_NOT_EXIST;
 168             addinfo = *db_it;
 169             BackendPtr ptr;
 170             return ptr;
 171         }
 172         std::list<std::string>::const_iterator t_it =
 173             map_it->m_targets.begin();
 174         for (; t_it != map_it->m_targets.end(); t_it++) {
 175             if (!targets_dedup[*t_it])
 176             {
 177                 targets_dedup[*t_it] = true;
 178                 b->m_targets.push_back(*t_it);
 179             }
 180         }
 181
 182         // see if we have a route conflict.
 183         if (!first_route && b->m_route != map_it->m_route)
 184         {
 185             // we have a conflict.. routing must be same for all
 186             error_code =  YAZ_BIB1_COMBI_OF_SPECIFIED_DATABASES_UNSUPP;
 187             BackendPtr ptr;
 188             return ptr;
 189         }
 190         b->m_route = map_it->m_route;
 191         if (!first_route && b->query_encoding != map_it->query_encoding)
 192         {
 193             // we have a conflict. query encoding must be same for all
 194             error_code =  YAZ_BIB1_COMBI_OF_SPECIFIED_DATABASES_UNSUPP;
 195             BackendPtr ptr;
 196             return ptr;
 197         }
 198         b->query_encoding = map_it->query_encoding;
 199         first_route = false;
 200     }
 201     return b;
 202 }
 203
 204 yf::VirtualDB::BackendPtr yf::VirtualDB::Frontend::init_backend(
 205     std::list<std::string> databases, mp::Package &package,
 206     int &error_code, std::string &addinfo)
 207 {
 208     BackendPtr b = create_backend_from_databases(databases, error_code,
 209                                                  addinfo);
 210     if (!b)
 211         return b;
 212     Package init_package(b->m_backend_session, package.origin());
 213     init_package.copy_filter(package);
 214
 215     mp::odr odr;
 216
 217     Z_APDU *init_apdu = zget_APDU(odr, Z_APDU_initRequest);
 218
 219     mp::util::set_vhost_otherinfo(&init_apdu->u.initRequest->otherInfo, odr,
 220                                    b->m_targets);
 221     Z_InitRequest *req = init_apdu->u.initRequest;
 222
 223     // copy stuff from Frontend Init Request
 224     Z_GDU *org_gdu = m_init_gdu.get();
 225     Z_InitRequest *org_init = org_gdu->u.z3950->u.initRequest;
 226
 227     req->idAuthentication = org_init->idAuthentication;
 228     req->implementationId = org_init->implementationId;
 229     req->implementationName = org_init->implementationName;
 230     req->implementationVersion = org_init->implementationVersion;
 231     *req->preferredMessageSize = *org_init->preferredMessageSize;
 232     *req->maximumRecordSize = *org_init->maximumRecordSize;
 233
 234     ODR_MASK_SET(req->options, Z_Options_search);
 235     ODR_MASK_SET(req->options, Z_Options_present);
 236     ODR_MASK_SET(req->options, Z_Options_namedResultSets);
 237     ODR_MASK_SET(req->options, Z_Options_scan);
 238
 239     ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_1);
 240     ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_2);
 241     ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_3);
 242
 243     init_package.request() = init_apdu;
 244
 245     init_package.move(b->m_route);  // sending init
 246
 247     Z_GDU *gdu = init_package.response().get();
 248     // we hope to get an init response
 249     error_code = YAZ_BIB1_DATABASE_UNAVAILABLE;
 250     if (gdu && gdu->which == Z_GDU_Z3950
 251         && gdu->u.z3950->which == Z_APDU_initResponse)
 252     {
 253         Z_InitResponse *res = gdu->u.z3950->u.initResponse;
 254         if (ODR_MASK_GET(res->options, Z_Options_namedResultSets))
 255         {
 256             b->m_named_result_sets = true;
 257         }
 258         if (*res->result && !init_package.session().is_closed())
 259         {
 260             m_backend_list.push_back(b);
 261             return b;
 262         }
 263         mp::util::get_init_diagnostics(res, error_code, addinfo);
 264     }
 265     if (!init_package.session().is_closed())
 266     {
 267         Package close_package(b->m_backend_session, package.origin());
 268         close_package.copy_filter(package);
 269         close_package.session().close();
 270         close_package.move(b->m_route);  // closing it
 271     }
 272     BackendPtr null;
 273     return null;
 274 }
 275
 276 void yf::VirtualDB::Frontend::search(mp::Package &package, Z_APDU *apdu_req)
 277 {
 278     Z_SearchRequest *req = apdu_req->u.searchRequest;
 279     std::string vhost;
 280     std::string resultSetId = req->resultSetName;
 281     mp::odr odr;
 282
 283     std::list<std::string> databases;
 284     int i;
 285     for (i = 0; i<req->num_databaseNames; i++)
 286         databases.push_back(req->databaseNames[i]);
 287
 288     Sets_it sets_it = m_sets.find(req->resultSetName);
 289     if (sets_it != m_sets.end())
 290     {
 291         // result set already exist
 292         // if replace indicator is off: we return diagnostic if
 293         // result set already exist.
 294         if (*req->replaceIndicator == 0)
 295         {
 296             Z_APDU *apdu =
 297                 odr.create_searchResponse(
 298                     apdu_req,
 299                     YAZ_BIB1_RESULT_SET_EXISTS_AND_REPLACE_INDICATOR_OFF,
 300                     0);
 301             package.response() = apdu;
 302
 303             return;
 304         }
 305         sets_it->second.m_backend->m_number_of_sets--;
 306     }
 307     // pick up any existing database with named result sets ..
 308     // or one which has no result sets.. yet.
 309     BackendPtr b; // null for now
 310     std::list<BackendPtr>::const_iterator map_it;
 311     map_it = m_backend_list.begin();
 312     for (; map_it != m_backend_list.end(); map_it++)
 313     {
 314         BackendPtr tmp = *map_it;
 315         if (tmp->m_frontend_databases == databases &&
 316             (tmp->m_named_result_sets ||
 317              tmp->m_number_of_sets == 0))
 318         {
 319             b = *map_it;
 320             break;
 321         }
 322     }
 323     if (!b)  // no backend yet. Must create a new one
 324     {
 325         int error_code;
 326         std::string addinfo;
 327         b = init_backend(databases, package, error_code, addinfo);
 328         if (!b)
 329         {
 330             // did not get a backend (unavailable somehow?)
 331
 332             Z_APDU *apdu =
 333                 odr.create_searchResponse(
 334                     apdu_req, error_code, addinfo.c_str());
 335             package.response() = apdu;
 336             return;
 337         }
 338     }
 339     m_sets.erase(req->resultSetName);
 340     // sending search to backend
 341     Package search_package(b->m_backend_session, package.origin());
 342
 343     search_package.copy_filter(package);
 344
 345     std::string backend_setname;
 346     if (b->m_named_result_sets)
 347     {
 348         backend_setname = std::string(req->resultSetName);
 349     }
 350     else
 351     {
 352         backend_setname = "default";
 353         req->resultSetName = odr_strdup(odr, backend_setname.c_str());
 354     }
 355
 356     // pick first targets spec and move the databases from it ..
 357     std::list<std::string>::const_iterator t_it = b->m_targets.begin();
 358     if (t_it != b->m_targets.end())
 359     {
 360         mp::util::set_databases_from_zurl(odr, *t_it,
 361                                                 &req->num_databaseNames,
 362                                                 &req->databaseNames);
 363     }
 364
 365     if (b->query_encoding.length() &&
 366         (req->query->which == Z_Query_type_1 ||
 367          req->query->which == Z_Query_type_101))
 368     {
 369         yaz_iconv_t cd = yaz_iconv_open(b->query_encoding.c_str(), "UTF-8");
 370         if (cd)
 371         {
 372             int r = yaz_query_charset_convert_rpnquery_check(
 373                 req->query->u.type_1, odr, cd);
 374             yaz_iconv_close(cd);
 375             if (r)
 376                 yaz_log(YLOG_LOG, "query could not be converted");
 377         }
 378     }
 379     *req->replaceIndicator = 1;
 380
 381     search_package.request() = yazpp_1::GDU(apdu_req);
 382
 383     search_package.move(b->m_route);
 384
 385     if (search_package.session().is_closed())
 386     {
 387         package.response() = search_package.response();
 388         package.session().close();
 389         return;
 390     }
 391     b->m_number_of_sets++;
 392
 393     m_sets[resultSetId] = VirtualDB::Set(b, backend_setname);
 394     fixup_package(search_package, b);
 395     package.response() = search_package.response();
 396 }
 397
 398 yf::VirtualDB::Frontend::Frontend(Rep *rep)
 399 {
 400     m_p = rep;
 401     m_is_virtual = false;
 402 }
 403
 404 void yf::VirtualDB::Frontend::close(mp::Package &package)
 405 {
 406     std::list<BackendPtr>::const_iterator b_it;
 407
 408     for (b_it = m_backend_list.begin(); b_it != m_backend_list.end(); b_it++)
 409     {
 410         (*b_it)->m_backend_session.close();
 411         Package close_package((*b_it)->m_backend_session, package.origin());
 412         close_package.copy_filter(package);
 413         close_package.move((*b_it)->m_route);
 414     }
 415     m_backend_list.clear();
 416 }
 417
 418 yf::VirtualDB::Frontend::~Frontend()
 419 {
 420 }
 421
 422 yf::VirtualDB::FrontendPtr yf::VirtualDB::Rep::get_frontend(mp::Package &package)
 423 {
 424     boost::mutex::scoped_lock lock(m_mutex);
 425
 426     std::map<mp::Session,yf::VirtualDB::FrontendPtr>::iterator it;
 427
 428     while(true)
 429     {
 430         it = m_clients.find(package.session());
 431         if (it == m_clients.end())
 432             break;
 433
 434         if (!it->second->m_in_use)
 435         {
 436             it->second->m_in_use = true;
 437             return it->second;
 438         }
 439         m_cond_session_ready.wait(lock);
 440     }
 441     FrontendPtr f(new Frontend(this));
 442     m_clients[package.session()] = f;
 443     f->m_in_use = true;
 444     return f;
 445 }
 446
 447 void yf::VirtualDB::Rep::release_frontend(mp::Package &package)
 448 {
 449     boost::mutex::scoped_lock lock(m_mutex);
 450     std::map<mp::Session,yf::VirtualDB::FrontendPtr>::iterator it;
 451
 452     it = m_clients.find(package.session());
 453     if (it != m_clients.end())
 454     {
 455         if (package.session().is_closed())
 456         {
 457             it->second->close(package);
 458             m_clients.erase(it);
 459         }
 460         else
 461         {
 462             it->second->m_in_use = false;
 463         }
 464         m_cond_session_ready.notify_all();
 465     }
 466 }
 467
 468
 469 yf::VirtualDB::Set::Set(BackendPtr b, std::string setname)
 470     :  m_backend(b), m_setname(setname)
 471 {
 472 }
 473
 474
 475 yf::VirtualDB::Set::Set()
 476 {
 477 }
 478
 479
 480 yf::VirtualDB::Set::~Set()
 481 {
 482 }
 483
 484 yf::VirtualDB::Map::Map(std::string database,
 485                         std::list<std::string> targets, std::string route)
 486     : m_dbpattern(database), m_targets(targets), m_route(route)
 487 {
 488 }
 489
 490 yf::VirtualDB::Map::Map(std::string database,
 491                         std::string target, std::string route)
 492     : m_dbpattern(database), m_route(route)
 493 {
 494     m_targets.push_back(target);
 495 }
 496
 497
 498 yf::VirtualDB::Map::Map()
 499 {
 500 }
 501
 502 bool yf::VirtualDB::Map::match(const std::string db) const
 503 {
 504     std::string norm_db = mp::util::database_name_normalize(db);
 505     if (yaz_match_glob(m_dbpattern.c_str(), norm_db.c_str()))
 506         return true;
 507     return false;
 508 }
 509
 510 yf::VirtualDB::VirtualDB() : m_p(new VirtualDB::Rep)
 511 {
 512     m_p->pass_vhosts = false;
 513 }
 514
 515 yf::VirtualDB::~VirtualDB() {
 516 }
 517
 518 void yf::VirtualDB::Frontend::fixup_npr_record(ODR odr, Z_NamePlusRecord *npr,
 519                                              BackendPtr b)
 520 {
 521     if (npr->databaseName)
 522     {
 523         std::string b_database = std::string(npr->databaseName);
 524
 525         // consider each of the frontend databases..
 526         std::list<std::string>::const_iterator db_it;
 527         for (db_it = b->m_frontend_databases.begin();
 528              db_it != b->m_frontend_databases.end(); db_it++)
 529         {
 530             // see which target it corresponds to.. (if any)
 531             std::list<VirtualDB::Map>::const_iterator map_it =
 532                 m_p->m_maps.begin();
 533             while (map_it != m_p->m_maps.end())
 534             {
 535                 if (map_it->match(*db_it))
 536                     break;
 537                 map_it++;
 538             }
 539             if (map_it != m_p->m_maps.end())
 540             {
 541                 std::list<std::string>::const_iterator t
 542                     = map_it->m_targets.begin();
 543                 while (t != map_it->m_targets.end())
 544                 {
 545                     if (*t == b_database)
 546                     {
 547                         npr->databaseName = odr_strdup(odr, (*db_it).c_str());
 548                         return;
 549                     }
 550                     t++;
 551                 }
 552             }
 553
 554         }
 555         db_it = b->m_frontend_databases.begin();
 556         if (db_it != b->m_frontend_databases.end())
 557         {
 558             std::string database = *db_it;
 559             npr->databaseName = odr_strdup(odr, database.c_str());
 560         }
 561     }
 562 }
 563
 564 void yf::VirtualDB::Frontend::fixup_npr_records(ODR odr, Z_Records *records,
 565                                               BackendPtr b)
 566 {
 567     if (records && records->which == Z_Records_DBOSD)
 568     {
 569         Z_NamePlusRecordList *nprlist = records->u.databaseOrSurDiagnostics;
 570         int i;
 571         for (i = 0; i < nprlist->num_records; i++)
 572         {
 573             fixup_npr_record(odr, nprlist->records[i], b);
 574         }
 575     }
 576 }
 577
 578 void yf::VirtualDB::Frontend::fixup_package(mp::Package &p, BackendPtr b)
 579 {
 580     Z_GDU *gdu = p.response().get();
 581     mp::odr odr;
 582
 583     if (gdu && gdu->which == Z_GDU_Z3950)
 584     {
 585         Z_APDU *apdu = gdu->u.z3950;
 586         if (apdu->which == Z_APDU_presentResponse)
 587         {
 588             fixup_npr_records(odr, apdu->u.presentResponse->records, b);
 589             p.response() = gdu;
 590         }
 591         else if (apdu->which == Z_APDU_searchResponse)
 592         {
 593             fixup_npr_records(odr,  apdu->u.searchResponse->records, b);
 594             p.response() = gdu;
 595         }
 596     }
 597 }
 598
 599 void yf::VirtualDB::Frontend::present(mp::Package &package, Z_APDU *apdu_req)
 600 {
 601     Z_PresentRequest *req = apdu_req->u.presentRequest;
 602     std::string resultSetId = req->resultSetId;
 603     mp::odr odr;
 604
 605     Sets_it sets_it = m_sets.find(resultSetId);
 606     if (sets_it == m_sets.end())
 607     {
 608         Z_APDU *apdu =
 609             odr.create_presentResponse(
 610                 apdu_req,
 611                 YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST,
 612                 resultSetId.c_str());
 613         package.response() = apdu;
 614         return;
 615     }
 616     Session *id =
 617         new mp::Session(sets_it->second.m_backend->m_backend_session);
 618
 619     // sending present to backend
 620     Package present_package(*id, package.origin());
 621     present_package.copy_filter(package);
 622
 623     req->resultSetId = odr_strdup(odr, sets_it->second.m_setname.c_str());
 624
 625     present_package.request() = yazpp_1::GDU(apdu_req);
 626
 627     present_package.move(sets_it->second.m_backend->m_route);
 628
 629     fixup_package(present_package, sets_it->second.m_backend);
 630
 631     if (present_package.session().is_closed())
 632     {
 633         package.response() = present_package.response();
 634         package.session().close();
 635         return;
 636     }
 637     else
 638     {
 639         package.response() = present_package.response();
 640     }
 641     delete id;
 642 }
 643
 644 int yf::VirtualDB::Frontend::relay_apdu(mp::Package &package, Z_APDU *apdu_req)
 645 {
 646     int no = 0;
 647     std::list<BackendPtr>::const_iterator map_it;
 648     map_it = m_backend_list.begin();
 649     for (; map_it != m_backend_list.end(); map_it++)
 650     {
 651         BackendPtr b = *map_it;
 652
 653         Package relay_package(b->m_backend_session, package.origin());
 654         relay_package.copy_filter(package);
 655
 656         relay_package.request() = yazpp_1::GDU(apdu_req);
 657
 658         relay_package.move(b->m_route);
 659         package.response() = relay_package.response();
 660         no++;
 661     }
 662     return no;
 663 }
 664
 665 void yf::VirtualDB::Frontend::scan(mp::Package &package, Z_APDU *apdu_req)
 666 {
 667     Z_ScanRequest *req = apdu_req->u.scanRequest;
 668     std::string vhost;
 669     mp::odr odr;
 670
 671     std::list<std::string> databases;
 672     int i;
 673     for (i = 0; i<req->num_databaseNames; i++)
 674         databases.push_back(req->databaseNames[i]);
 675
 676     BackendPtr b;
 677     // pick up any existing backend with a database match
 678     std::list<BackendPtr>::const_iterator map_it;
 679     map_it = m_backend_list.begin();
 680     for (; map_it != m_backend_list.end(); map_it++)
 681     {
 682         BackendPtr tmp = *map_it;
 683         if (tmp->m_frontend_databases == databases)
 684             break;
 685     }
 686     if (map_it != m_backend_list.end())
 687         b = *map_it;
 688     if (!b)  // no backend yet. Must create a new one
 689     {
 690         int error_code;
 691         std::string addinfo;
 692         b = init_backend(databases, package, error_code, addinfo);
 693         if (!b)
 694         {
 695             // did not get a backend (unavailable somehow?)
 696             Z_APDU *apdu =
 697                 odr.create_scanResponse(
 698                     apdu_req, error_code, addinfo.c_str());
 699             package.response() = apdu;
 700
 701             return;
 702         }
 703     }
 704     // sending scan to backend
 705     Package scan_package(b->m_backend_session, package.origin());
 706
 707     scan_package.copy_filter(package);
 708
 709     // pick first targets spec and move the databases from it ..
 710     std::list<std::string>::const_iterator t_it = b->m_targets.begin();
 711     if (t_it != b->m_targets.end())
 712     {
 713         mp::util::set_databases_from_zurl(odr, *t_it,
 714                                                 &req->num_databaseNames,
 715                                                 &req->databaseNames);
 716     }
 717
 718     if (b->query_encoding.length())
 719     {
 720         yaz_iconv_t cd = yaz_iconv_open(b->query_encoding.c_str(), "UTF-8");
 721         if (cd)
 722         {
 723             yaz_query_charset_convert_apt(req->termListAndStartPoint, odr, cd);
 724             yaz_iconv_close(cd);
 725         }
 726     }
 727
 728     scan_package.request() = yazpp_1::GDU(apdu_req);
 729
 730     scan_package.move(b->m_route);
 731
 732     if (scan_package.session().is_closed())
 733     {
 734         package.response() = scan_package.response();
 735         package.session().close();
 736         return;
 737     }
 738     package.response() = scan_package.response();
 739 }
 740
 741
 742 void yf::VirtualDB::add_map_db2targets(std::string db,
 743                                        std::list<std::string> targets,
 744                                        std::string route)
 745 {
 746     m_p->m_maps.push_back(
 747         VirtualDB::Map(mp::util::database_name_normalize(db), targets, route));
 748 }
 749
 750
 751 void yf::VirtualDB::add_map_db2target(std::string db,
 752                                       std::string target,
 753                                       std::string route)
 754
 755 {
 756     m_p->m_maps.push_back(
 757         VirtualDB::Map(mp::util::database_name_normalize(db), target, route));
 758 }
 759
 760 void yf::VirtualDB::process(mp::Package &package) const
 761 {
 762     FrontendPtr f = m_p->get_frontend(package);
 763
 764     Z_GDU *gdu = package.request().get();
 765
 766     if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 767         Z_APDU_initRequest && !f->m_is_virtual)
 768     {
 769         Z_InitRequest *req = gdu->u.z3950->u.initRequest;
 770
 771         std::list<std::string> vhosts;
 772         mp::util::get_vhost_otherinfo(req->otherInfo, vhosts);
 773
 774         if (vhosts.size() > 0 && m_p->pass_vhosts)
 775         {
 776             package.move();
 777         }
 778         else
 779         {
 780             f->m_init_gdu = gdu;
 781
 782             mp::odr odr;
 783             Z_APDU *apdu = odr.create_initResponse(gdu->u.z3950, 0, 0);
 784             Z_InitResponse *resp = apdu->u.initResponse;
 785
 786             int i;
 787             static const int masks[] = {
 788                 Z_Options_search,
 789                 Z_Options_present,
 790                 Z_Options_namedResultSets,
 791                 Z_Options_scan,
 792                 -1
 793             };
 794             for (i = 0; masks[i] != -1; i++)
 795                 if (ODR_MASK_GET(req->options, masks[i]))
 796                     ODR_MASK_SET(resp->options, masks[i]);
 797
 798             static const int versions[] = {
 799                 Z_ProtocolVersion_1,
 800                 Z_ProtocolVersion_2,
 801                 Z_ProtocolVersion_3,
 802                 -1
 803             };
 804             for (i = 0; versions[i] != -1; i++)
 805                 if (ODR_MASK_GET(req->protocolVersion, versions[i]))
 806                     ODR_MASK_SET(resp->protocolVersion, versions[i]);
 807                 else
 808                     break;
 809
 810             *resp->preferredMessageSize = *req->preferredMessageSize;
 811             *resp->maximumRecordSize = *req->maximumRecordSize;
 812
 813             package.response() = apdu;
 814             f->m_is_virtual = true;
 815         }
 816     }
 817     else if (!f->m_is_virtual)
 818         package.move();
 819     else if (gdu && gdu->which == Z_GDU_Z3950)
 820     {
 821         Z_APDU *apdu = gdu->u.z3950;
 822         if (apdu->which == Z_APDU_initRequest)
 823         {
 824             mp::odr odr;
 825
 826             package.response() = odr.create_close(
 827                 apdu,
 828                 Z_Close_protocolError,
 829                 "double init");
 830
 831             package.session().close();
 832         }
 833         else if (apdu->which == Z_APDU_searchRequest)
 834         {
 835             f->search(package, apdu);
 836         }
 837         else if (apdu->which == Z_APDU_presentRequest)
 838         {
 839             f->present(package, apdu);
 840         }
 841         else if (apdu->which == Z_APDU_scanRequest)
 842         {
 843             f->scan(package, apdu);
 844         }
 845         else if (apdu->which == Z_APDU_close)
 846         {
 847             if (f->relay_apdu(package, apdu) == 0)
 848             {
 849                 mp::odr odr;
 850
 851                 package.response() = odr.create_close(
 852                     apdu, Z_Close_finished, "virt_db");
 853
 854                 package.session().close();
 855             }
 856         }
 857         else
 858         {
 859             mp::odr odr;
 860
 861             package.response() = odr.create_close(
 862                 apdu, Z_Close_protocolError,
 863                 "unsupported APDU in filter_virt_db");
 864
 865             package.session().close();
 866         }
 867     }
 868     m_p->release_frontend(package);
 869 }
 870
 871 void mp::filter::VirtualDB::configure(const xmlNode * ptr, bool test_only)
 872 {
 873     for (ptr = ptr->children; ptr; ptr = ptr->next)
 874     {
 875         if (ptr->type != XML_ELEMENT_NODE)
 876             continue;
 877         if (!strcmp((const char *) ptr->name, "pass-vhosts"))
 878         {
 879             m_p->pass_vhosts = mp::xml::get_bool(ptr, false);
 880         }
 881         else if (!strcmp((const char *) ptr->name, "virtual"))
 882         {
 883             std::string query_encoding;
 884             std::string database;
 885             std::list<std::string> targets;
 886             xmlNode *v_node = ptr->children;
 887             for (; v_node; v_node = v_node->next)
 888             {
 889                 if (v_node->type != XML_ELEMENT_NODE)
 890                     continue;
 891
 892                 if (mp::xml::is_element_mp(v_node, "database"))
 893                     database = mp::xml::get_text(v_node);
 894                 else if (mp::xml::is_element_mp(v_node, "target"))
 895                     targets.push_back(mp::xml::get_text(v_node));
 896                 else if (mp::xml::is_element_mp(v_node, "query-encoding"))
 897                     targets.push_back(mp::xml::get_text(v_node));
 898                 else
 899                     throw mp::filter::FilterException
 900                         ("Bad element "
 901                          + std::string((const char *) v_node->name)
 902                          + " in virtual section"
 903                             );
 904             }
 905             std::string route = mp::xml::get_route(ptr);
 906
 907             VirtualDB::Map vmap(mp::util::database_name_normalize(database),
 908                                 targets, route);
 909             vmap.query_encoding = query_encoding;
 910             m_p->m_maps.push_back(vmap);
 911         }
 912         else
 913         {
 914             throw mp::filter::FilterException
 915                 ("Bad element "
 916                  + std::string((const char *) ptr->name)
 917                  + " in virt_db filter");
 918         }
 919     }
 920 }
 921
 922 static mp::filter::Base* filter_creator()
 923 {
 924     return new mp::filter::VirtualDB;
 925 }
 926
 927 extern "C" {
 928     struct metaproxy_1_filter_struct metaproxy_1_filter_virt_db = {
 929         0,
 930         "virt_db",
 931         filter_creator
 932     };
 933 }
 934
 935
 936 /*
 937  * Local variables:
 938  * c-basic-offset: 4
 939  * c-file-style: "Stroustrup"
 940  * indent-tabs-mode: nil
 941  * End:
 942  * vim: shiftwidth=4 tabstop=8 expandtab
 943  */
 944