src/filter_virt_db.cpp

   1 /* $Id: filter_virt_db.cpp,v 1.8 2005-10-25 23:04:06 adam Exp $
   2    Copyright (c) 2005, Index Data.
   3
   4 %LICENSE%
   5  */
   6
   7 #include "config.hpp"
   8
   9 #include "filter.hpp"
  10 #include "router.hpp"
  11 #include "package.hpp"
  12
  13 #include <boost/thread/mutex.hpp>
  14
  15 #include "filter_virt_db.hpp"
  16
  17 #include <yaz/zgdu.h>
  18 #include <yaz/log.h>
  19 #include <yaz/otherinfo.h>
  20 #include <yaz/diagbib1.h>
  21
  22 #include <list>
  23 #include <map>
  24 #include <iostream>
  25
  26 namespace yf = yp2::filter;
  27
  28 namespace yp2 {
  29     namespace filter {
  30         struct Virt_db_set {
  31             Virt_db_set(yp2::Session &id, std::string setname,
  32                         std::string vhost);
  33             Virt_db_set();
  34             ~Virt_db_set();
  35
  36             yp2::Session m_backend_session;
  37             std::string m_backend_setname;
  38             std::string m_vhost;
  39         };
  40         struct Virt_db_session {
  41             Virt_db_session(yp2::Session &id, bool use_vhost);
  42             Virt_db_session();
  43             yp2::Session m_session;
  44             bool m_use_vhost;
  45             std::map<std::string,Virt_db_set> m_sets;
  46         };
  47         struct Virt_db_map {
  48             Virt_db_map(std::string vhost);
  49             Virt_db_map();
  50             std::string m_vhost;
  51         };
  52         class Virt_db::Rep {
  53             friend class Virt_db;
  54
  55             void release_session(Package &package);
  56             void init(Package &package, Z_APDU *apdu, bool &move_later);
  57             void search(Package &package, Z_APDU *apdu, bool &move_later);
  58             void present(Package &package, Z_APDU *apdu, bool &move_later);
  59         private:
  60             boost::mutex m_sessions_mutex;
  61             std::map<yp2::Session,Virt_db_session>m_sessions;
  62             std::map<std::string, Virt_db_map>m_maps;
  63
  64             typedef std::map<yp2::Session,Virt_db_session>::iterator Ses_it;
  65             typedef std::map<std::string,Virt_db_set>::iterator Sets_it;
  66         };
  67     }
  68 }
  69
  70 yf::Virt_db_set::Virt_db_set(yp2::Session &id, std::string setname,
  71                              std::string vhost)
  72     :   m_backend_session(id), m_backend_setname(setname), m_vhost(vhost)
  73 {
  74 }
  75
  76
  77 yf::Virt_db_set::Virt_db_set()
  78 {
  79 }
  80
  81
  82 yf::Virt_db_set::~Virt_db_set()
  83 {
  84 }
  85
  86 yf::Virt_db_map::Virt_db_map(std::string vhost)
  87     : m_vhost(vhost)
  88 {
  89 }
  90
  91 yf::Virt_db_map::Virt_db_map()
  92 {
  93 }
  94
  95 yf::Virt_db_session::Virt_db_session()
  96     : m_use_vhost(false)
  97 {
  98
  99 }
 100
 101 yf::Virt_db_session::Virt_db_session(yp2::Session &id,
 102                                      bool use_vhost) :
 103     m_session(id) , m_use_vhost(use_vhost)
 104 {
 105
 106 }
 107
 108 yf::Virt_db::Virt_db() {
 109     m_p = new Virt_db::Rep;
 110 }
 111
 112 yf::Virt_db::~Virt_db() {
 113     delete m_p;
 114 }
 115
 116 void yf::Virt_db::Rep::release_session(Package &package)
 117 {
 118     boost::mutex::scoped_lock lock(m_sessions_mutex);
 119
 120     m_sessions.erase(package.session());
 121 }
 122
 123 void yf::Virt_db::Rep::present(Package &package, Z_APDU *apdu, bool &move_later){
 124     Session *id = 0;
 125     Z_PresentRequest *req = apdu->u.presentRequest;
 126     std::string resultSetId = req->resultSetId;
 127     {
 128         boost::mutex::scoped_lock lock(m_sessions_mutex);
 129
 130         Ses_it it = m_sessions.find(package.session());
 131         if (it == m_sessions.end())
 132         {
 133             ODR odr = odr_createmem(ODR_ENCODE);
 134
 135             Z_APDU *apdu = zget_APDU(odr, Z_APDU_close);
 136
 137             *apdu->u.close->closeReason = Z_Close_protocolError;
 138             apdu->u.close->diagnosticInformation =
 139                 odr_strdup(odr, "no session for present request");
 140
 141             package.response() = apdu;
 142             package.session().close();
 143             odr_destroy(odr);
 144             assert(false);
 145             return;
 146         }
 147         if (it->second.m_use_vhost)
 148         {
 149             move_later = true;
 150             return;
 151         }
 152         Sets_it sets_it = it->second.m_sets.find(resultSetId);
 153         if (sets_it == it->second.m_sets.end())
 154         {
 155             ODR odr = odr_createmem(ODR_ENCODE);
 156             Z_APDU *apdu = zget_APDU(odr, Z_APDU_presentResponse);
 157
 158             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 159             apdu->u.presentResponse->records = rec;
 160             rec->which = Z_Records_NSD;
 161             rec->u.nonSurrogateDiagnostic =
 162                 zget_DefaultDiagFormat(
 163                     odr,
 164                     YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST,
 165                     resultSetId.c_str());
 166             package.response() = apdu;
 167             odr_destroy(odr);
 168             return;
 169         }
 170         id = new yp2::Session(sets_it->second.m_backend_session);
 171     }
 172     ODR odr = odr_createmem(ODR_ENCODE);
 173
 174     // sending present to backend
 175     Package present_package(*id, package.origin());
 176     present_package.copy_filter(package);
 177
 178     req->resultSetId = odr_strdup(odr, "default");
 179     present_package.request() = yazpp_1::GDU(apdu);
 180
 181     odr_destroy(odr);
 182
 183     present_package.move();
 184
 185     if (present_package.session().is_closed())
 186     {
 187         ODR odr = odr_createmem(ODR_ENCODE);
 188         Z_APDU *apdu = zget_APDU(odr, Z_APDU_presentResponse);
 189
 190         Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 191         apdu->u.presentResponse->records = rec;
 192         rec->which = Z_Records_NSD;
 193         rec->u.nonSurrogateDiagnostic =
 194             zget_DefaultDiagFormat(
 195                 odr,
 196                 YAZ_BIB1_RESULT_SET_NO_LONGER_EXISTS_UNILATERALLY_DELETED_BY_,
 197                 resultSetId.c_str());
 198         package.response() = apdu;
 199
 200         odr_destroy(odr);
 201
 202         boost::mutex::scoped_lock lock(m_sessions_mutex);
 203         Ses_it it = m_sessions.find(package.session());
 204         if (it != m_sessions.end())
 205             it->second.m_sets.erase(resultSetId);
 206     }
 207     else
 208     {
 209         package.response() = present_package.response();
 210     }
 211     delete id;
 212 }
 213
 214 void yf::Virt_db::Rep::search(Package &package, Z_APDU *apdu, bool &move_later)
 215 {
 216     Z_SearchRequest *req = apdu->u.searchRequest;
 217     std::string vhost;
 218     std::string database;
 219     std::string resultSetId = req->resultSetName;
 220     {
 221         boost::mutex::scoped_lock lock(m_sessions_mutex);
 222
 223         Ses_it it = m_sessions.find(package.session());
 224         if (it == m_sessions.end())
 225         {
 226             ODR odr = odr_createmem(ODR_ENCODE);
 227
 228             Z_APDU *apdu = zget_APDU(odr, Z_APDU_close);
 229
 230             *apdu->u.close->closeReason = Z_Close_protocolError;
 231             apdu->u.close->diagnosticInformation =
 232                 odr_strdup(odr, "no session for search request");
 233
 234             package.response() = apdu;
 235             package.session().close();
 236             odr_destroy(odr);
 237             return;
 238         }
 239         if (it->second.m_use_vhost)
 240         {
 241             move_later = true;
 242             return;
 243         }
 244         if (req->num_databaseNames != 1)
 245         {   // exactly one database must be specified
 246             ODR odr = odr_createmem(ODR_ENCODE);
 247             Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 248
 249             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 250             apdu->u.searchResponse->records = rec;
 251             rec->which = Z_Records_NSD;
 252             rec->u.nonSurrogateDiagnostic =
 253                 zget_DefaultDiagFormat(
 254                     odr, YAZ_BIB1_TOO_MANY_DATABASES_SPECIFIED, 0);
 255             package.response() = apdu;
 256
 257             odr_destroy(odr);
 258             return;
 259         }
 260         database = req->databaseNames[0];
 261         std::map<std::string, Virt_db_map>::iterator map_it;
 262         map_it = m_maps.find(database);
 263         if (map_it == m_maps.end())
 264         {   // no map for database: return diagnostic
 265             ODR odr = odr_createmem(ODR_ENCODE);
 266             Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 267
 268             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 269             apdu->u.searchResponse->records = rec;
 270             rec->which = Z_Records_NSD;
 271             rec->u.nonSurrogateDiagnostic =
 272                 zget_DefaultDiagFormat(
 273                     odr, YAZ_BIB1_DATABASE_DOES_NOT_EXIST, database.c_str());
 274             package.response() = apdu;
 275
 276             odr_destroy(odr);
 277             return;
 278         }
 279         if (*req->replaceIndicator == 0)
 280         {
 281             Sets_it sets_it = it->second.m_sets.find(req->resultSetName);
 282             if (sets_it != it->second.m_sets.end())
 283             {
 284                 ODR odr = odr_createmem(ODR_ENCODE);
 285                 Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 286
 287                 Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 288                 apdu->u.searchResponse->records = rec;
 289                 rec->which = Z_Records_NSD;
 290                 rec->u.nonSurrogateDiagnostic =
 291                     zget_DefaultDiagFormat(
 292                         odr,
 293                         YAZ_BIB1_RESULT_SET_EXISTS_AND_REPLACE_INDICATOR_OFF,
 294                         0);
 295                 package.response() = apdu;
 296
 297                 odr_destroy(odr);
 298                 return;
 299             }
 300         }
 301         it->second.m_sets.erase(req->resultSetName);
 302         vhost = map_it->second.m_vhost;
 303     }
 304     // we might look for an existing session with same vhost
 305     Session id;
 306     const char *vhost_cstr = vhost.c_str();
 307     if (true)
 308     {  // sending init to backend
 309         Package init_package(id, package.origin());
 310         init_package.copy_filter(package);
 311
 312         ODR odr = odr_createmem(ODR_ENCODE);
 313         Z_APDU *init_apdu = zget_APDU(odr, Z_APDU_initRequest);
 314
 315         yaz_oi_set_string_oidval(&init_apdu->u.initRequest->otherInfo, odr,
 316                                  VAL_PROXY, 1, vhost_cstr);
 317
 318         init_package.request() = init_apdu;
 319         odr_destroy(odr);
 320
 321         init_package.move();  // sending init
 322
 323         if (init_package.session().is_closed())
 324         {
 325             ODR odr = odr_createmem(ODR_ENCODE);
 326             Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 327
 328             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 329             apdu->u.searchResponse->records = rec;
 330             rec->which = Z_Records_NSD;
 331             rec->u.nonSurrogateDiagnostic =
 332                 zget_DefaultDiagFormat(
 333                     odr, YAZ_BIB1_DATABASE_UNAVAILABLE, database.c_str());
 334             package.response() = apdu;
 335
 336             odr_destroy(odr);
 337         }
 338     }
 339     // sending search to backend
 340     Package search_package(id, package.origin());
 341
 342     search_package.copy_filter(package);
 343     const char *sep = strchr(vhost_cstr, '/');
 344     ODR odr = odr_createmem(ODR_ENCODE);
 345     if (sep)
 346         req->databaseNames[0] = odr_strdup(odr, sep+1);
 347
 348     *req->replaceIndicator = 1;
 349
 350     std::string backend_resultSetId = "default";
 351     req->resultSetName = odr_strdup(odr, backend_resultSetId.c_str());
 352     search_package.request() = yazpp_1::GDU(apdu);
 353
 354     odr_destroy(odr);
 355
 356     search_package.move();
 357
 358     if (search_package.session().is_closed())
 359     {
 360         ODR odr = odr_createmem(ODR_ENCODE);
 361         Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 362
 363         Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 364         apdu->u.searchResponse->records = rec;
 365         rec->which = Z_Records_NSD;
 366         rec->u.nonSurrogateDiagnostic =
 367             zget_DefaultDiagFormat(
 368                 odr, YAZ_BIB1_DATABASE_UNAVAILABLE, database.c_str());
 369         package.response() = apdu;
 370
 371         odr_destroy(odr);
 372         return;
 373     }
 374     package.response() = search_package.response();
 375
 376     boost::mutex::scoped_lock lock(m_sessions_mutex);
 377     Ses_it it = m_sessions.find(package.session());
 378     if (it != m_sessions.end())
 379         it->second.m_sets[resultSetId] =
 380             Virt_db_set(id, backend_resultSetId, vhost);
 381 }
 382
 383 void yf::Virt_db::Rep::init(Package &package, Z_APDU *apdu, bool &move_later)
 384 {
 385     release_session(package);
 386     boost::mutex::scoped_lock lock(m_sessions_mutex);
 387
 388     Z_InitRequest *req = apdu->u.initRequest;
 389
 390     const char *vhost =
 391         yaz_oi_get_string_oidval(&req->otherInfo, VAL_PROXY, 1, 0);
 392     if (!vhost)
 393     {
 394         ODR odr = odr_createmem(ODR_ENCODE);
 395
 396         Z_APDU *apdu = zget_APDU(odr, Z_APDU_initResponse);
 397         Z_InitResponse *resp = apdu->u.initResponse;
 398
 399         int i;
 400         static const int masks[] = {
 401             Z_Options_search, Z_Options_present, Z_Options_namedResultSets, -1
 402         };
 403         for (i = 0; masks[i] != -1; i++)
 404             if (ODR_MASK_GET(req->options, masks[i]))
 405                 ODR_MASK_SET(resp->options, masks[i]);
 406
 407         static const int versions[] = {
 408             Z_ProtocolVersion_1,
 409             Z_ProtocolVersion_2,
 410             Z_ProtocolVersion_3,
 411             -1
 412         };
 413         for (i = 0; versions[i] != -1; i++)
 414             if (ODR_MASK_GET(req->protocolVersion, versions[i]))
 415                 ODR_MASK_SET(resp->protocolVersion, versions[i]);
 416             else
 417                 break;
 418
 419         package.response() = apdu;
 420
 421         odr_destroy(odr);
 422
 423         m_sessions[package.session()] = Virt_db_session(package.session(), false);
 424     }
 425     else
 426     {
 427         m_sessions[package.session()] = Virt_db_session(package.session(), true);
 428         move_later = true;
 429     }
 430 }
 431
 432 void yf::Virt_db::add_map_db2vhost(std::string db, std::string vhost)
 433 {
 434     m_p->m_maps[db] = Virt_db_map(vhost);
 435 }
 436
 437 void yf::Virt_db::process(Package &package) const
 438 {
 439     Z_GDU *gdu = package.request().get();
 440
 441     if (!gdu || gdu->which != Z_GDU_Z3950)
 442         package.move();
 443     else
 444     {
 445         bool move_later = false;
 446         Z_APDU *apdu = gdu->u.z3950;
 447         if (apdu->which == Z_APDU_initRequest)
 448         {
 449             m_p->init(package, apdu, move_later);
 450         }
 451         else if (apdu->which == Z_APDU_searchRequest)
 452         {
 453             m_p->search(package, apdu, move_later);
 454         }
 455         else if (apdu->which == Z_APDU_presentRequest)
 456         {
 457             m_p->present(package, apdu, move_later);
 458         }
 459         else
 460         {
 461             ODR odr = odr_createmem(ODR_ENCODE);
 462
 463             Z_APDU *apdu = zget_APDU(odr, Z_APDU_close);
 464
 465             *apdu->u.close->closeReason = Z_Close_protocolError;
 466
 467             apdu->u.close->diagnosticInformation =
 468                 odr_strdup(odr, "unsupported APDU in filter_virt_db");
 469
 470             package.response() = apdu;
 471             package.session().close();
 472             odr_destroy(odr);
 473         }
 474         if (move_later)
 475             package.move();
 476     }
 477     if (package.session().is_closed())
 478         m_p->release_session(package);
 479 }
 480
 481
 482 /*
 483  * Local variables:
 484  * c-basic-offset: 4
 485  * indent-tabs-mode: nil
 486  * c-file-style: "stroustrup"
 487  * End:
 488  * vim: shiftwidth=4 tabstop=8 expandtab
 489  */