src/filter_virt_db.cpp

   1 /* $Id: filter_virt_db.cpp,v 1.10 2005-10-29 15:54:29 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, bool named_result_sets);
  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             bool m_named_result_sets;
  40         };
  41         struct Virt_db_session {
  42             Virt_db_session(yp2::Session &id, bool use_vhost);
  43             Virt_db_session();
  44             yp2::Session m_session;
  45             bool m_use_vhost;
  46             std::map<std::string,Virt_db_set> m_sets;
  47         };
  48         struct Virt_db_map {
  49             Virt_db_map(std::string vhost);
  50             Virt_db_map();
  51             std::string m_vhost;
  52         };
  53         class Virt_db::Rep {
  54             friend class Virt_db;
  55
  56             void release_session(Package &package);
  57             void init(Package &package, Z_APDU *apdu, bool &move_later);
  58             void search(Package &package, Z_APDU *apdu, bool &move_later);
  59             void present(Package &package, Z_APDU *apdu, bool &move_later);
  60         private:
  61             boost::mutex m_sessions_mutex;
  62             std::map<yp2::Session,Virt_db_session>m_sessions;
  63             std::map<std::string, Virt_db_map>m_maps;
  64
  65             typedef std::map<yp2::Session,Virt_db_session>::iterator Ses_it;
  66             typedef std::map<std::string,Virt_db_set>::iterator Sets_it;
  67         };
  68     }
  69 }
  70
  71 yf::Virt_db_set::Virt_db_set(yp2::Session &id, std::string setname,
  72                              std::string vhost, bool named_result_sets)
  73     :   m_backend_session(id), m_backend_setname(setname), m_vhost(vhost),
  74         m_named_result_sets(named_result_sets)
  75 {
  76 }
  77
  78
  79 yf::Virt_db_set::Virt_db_set()
  80 {
  81 }
  82
  83
  84 yf::Virt_db_set::~Virt_db_set()
  85 {
  86 }
  87
  88 yf::Virt_db_map::Virt_db_map(std::string vhost)
  89     : m_vhost(vhost)
  90 {
  91 }
  92
  93 yf::Virt_db_map::Virt_db_map()
  94 {
  95 }
  96
  97 yf::Virt_db_session::Virt_db_session()
  98     : m_use_vhost(false)
  99 {
 100
 101 }
 102
 103 yf::Virt_db_session::Virt_db_session(yp2::Session &id,
 104                                      bool use_vhost) :
 105     m_session(id) , m_use_vhost(use_vhost)
 106 {
 107
 108 }
 109
 110 yf::Virt_db::Virt_db() : m_p(new Virt_db::Rep)
 111 {
 112 }
 113
 114 yf::Virt_db::~Virt_db() {
 115 }
 116
 117 void yf::Virt_db::Rep::release_session(Package &package)
 118 {
 119     boost::mutex::scoped_lock lock(m_sessions_mutex);
 120
 121     m_sessions.erase(package.session());
 122 }
 123
 124 void yf::Virt_db::Rep::present(Package &package, Z_APDU *apdu, bool &move_later){
 125     Session *id = 0;
 126     Z_PresentRequest *req = apdu->u.presentRequest;
 127     std::string resultSetId = req->resultSetId;
 128     {
 129         boost::mutex::scoped_lock lock(m_sessions_mutex);
 130
 131         Ses_it it = m_sessions.find(package.session());
 132         if (it == m_sessions.end())
 133         {
 134             ODR odr = odr_createmem(ODR_ENCODE);
 135
 136             Z_APDU *apdu = zget_APDU(odr, Z_APDU_close);
 137
 138             *apdu->u.close->closeReason = Z_Close_protocolError;
 139             apdu->u.close->diagnosticInformation =
 140                 odr_strdup(odr, "no session for present request");
 141
 142             package.response() = apdu;
 143             package.session().close();
 144             odr_destroy(odr);
 145             assert(false);
 146             return;
 147         }
 148         if (it->second.m_use_vhost)
 149         {
 150             move_later = true;
 151             return;
 152         }
 153         Sets_it sets_it = it->second.m_sets.find(resultSetId);
 154         if (sets_it == it->second.m_sets.end())
 155         {
 156             ODR odr = odr_createmem(ODR_ENCODE);
 157             Z_APDU *apdu = zget_APDU(odr, Z_APDU_presentResponse);
 158
 159             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 160             apdu->u.presentResponse->records = rec;
 161             rec->which = Z_Records_NSD;
 162             rec->u.nonSurrogateDiagnostic =
 163                 zget_DefaultDiagFormat(
 164                     odr,
 165                     YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST,
 166                     resultSetId.c_str());
 167             package.response() = apdu;
 168             odr_destroy(odr);
 169             return;
 170         }
 171         id = new yp2::Session(sets_it->second.m_backend_session);
 172     }
 173     ODR odr = odr_createmem(ODR_ENCODE);
 174
 175     // sending present to backend
 176     Package present_package(*id, package.origin());
 177     present_package.copy_filter(package);
 178
 179     req->resultSetId = odr_strdup(odr, "default");
 180     present_package.request() = yazpp_1::GDU(apdu);
 181
 182     odr_destroy(odr);
 183
 184     present_package.move();
 185
 186     if (present_package.session().is_closed())
 187     {
 188         ODR odr = odr_createmem(ODR_ENCODE);
 189         Z_APDU *apdu = zget_APDU(odr, Z_APDU_presentResponse);
 190
 191         Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 192         apdu->u.presentResponse->records = rec;
 193         rec->which = Z_Records_NSD;
 194         rec->u.nonSurrogateDiagnostic =
 195             zget_DefaultDiagFormat(
 196                 odr,
 197                 YAZ_BIB1_RESULT_SET_NO_LONGER_EXISTS_UNILATERALLY_DELETED_BY_,
 198                 resultSetId.c_str());
 199         package.response() = apdu;
 200
 201         odr_destroy(odr);
 202
 203         boost::mutex::scoped_lock lock(m_sessions_mutex);
 204         Ses_it it = m_sessions.find(package.session());
 205         if (it != m_sessions.end())
 206             it->second.m_sets.erase(resultSetId);
 207     }
 208     else
 209     {
 210         package.response() = present_package.response();
 211     }
 212     delete id;
 213 }
 214
 215 void yf::Virt_db::Rep::search(Package &package, Z_APDU *apdu, bool &move_later)
 216 {
 217     Z_SearchRequest *req = apdu->u.searchRequest;
 218     std::string vhost;
 219     std::string database;
 220     std::string resultSetId = req->resultSetName;
 221     bool support_named_result_sets = false;  // whether backend supports it
 222     {
 223         boost::mutex::scoped_lock lock(m_sessions_mutex);
 224
 225         Ses_it it = m_sessions.find(package.session());
 226         if (it == m_sessions.end())
 227         {
 228             ODR odr = odr_createmem(ODR_ENCODE);
 229
 230             Z_APDU *apdu = zget_APDU(odr, Z_APDU_close);
 231
 232             *apdu->u.close->closeReason = Z_Close_protocolError;
 233             apdu->u.close->diagnosticInformation =
 234                 odr_strdup(odr, "no session for search request");
 235
 236             package.response() = apdu;
 237             package.session().close();
 238             odr_destroy(odr);
 239             return;
 240         }
 241         if (it->second.m_use_vhost)
 242         {
 243             move_later = true;
 244             return;
 245         }
 246         if (req->num_databaseNames != 1)
 247         {   // exactly one database must be specified
 248             ODR odr = odr_createmem(ODR_ENCODE);
 249             Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 250
 251             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 252             apdu->u.searchResponse->records = rec;
 253             rec->which = Z_Records_NSD;
 254             rec->u.nonSurrogateDiagnostic =
 255                 zget_DefaultDiagFormat(
 256                     odr, YAZ_BIB1_TOO_MANY_DATABASES_SPECIFIED, 0);
 257             package.response() = apdu;
 258
 259             odr_destroy(odr);
 260             return;
 261         }
 262         database = req->databaseNames[0];
 263         std::map<std::string, Virt_db_map>::iterator map_it;
 264         map_it = m_maps.find(database);
 265         if (map_it == m_maps.end())
 266         {   // no map for database: return diagnostic
 267             ODR odr = odr_createmem(ODR_ENCODE);
 268             Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 269
 270             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 271             apdu->u.searchResponse->records = rec;
 272             rec->which = Z_Records_NSD;
 273             rec->u.nonSurrogateDiagnostic =
 274                 zget_DefaultDiagFormat(
 275                     odr, YAZ_BIB1_DATABASE_DOES_NOT_EXIST, database.c_str());
 276             package.response() = apdu;
 277
 278             odr_destroy(odr);
 279             return;
 280         }
 281         if (*req->replaceIndicator == 0)
 282         {
 283             Sets_it sets_it = it->second.m_sets.find(req->resultSetName);
 284             if (sets_it != it->second.m_sets.end())
 285             {
 286                 ODR odr = odr_createmem(ODR_ENCODE);
 287                 Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 288
 289                 Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 290                 apdu->u.searchResponse->records = rec;
 291                 rec->which = Z_Records_NSD;
 292                 rec->u.nonSurrogateDiagnostic =
 293                     zget_DefaultDiagFormat(
 294                         odr,
 295                         YAZ_BIB1_RESULT_SET_EXISTS_AND_REPLACE_INDICATOR_OFF,
 296                         0);
 297                 package.response() = apdu;
 298
 299                 odr_destroy(odr);
 300                 return;
 301             }
 302         }
 303         it->second.m_sets.erase(req->resultSetName);
 304         vhost = map_it->second.m_vhost;
 305     }
 306     // we might look for an existing session with same vhost
 307     Session id;
 308     const char *vhost_cstr = vhost.c_str();
 309     if (true)
 310     {  // sending init to backend
 311         Package init_package(id, package.origin());
 312         init_package.copy_filter(package);
 313
 314         ODR odr = odr_createmem(ODR_ENCODE);
 315         Z_APDU *init_apdu = zget_APDU(odr, Z_APDU_initRequest);
 316
 317         yaz_oi_set_string_oidval(&init_apdu->u.initRequest->otherInfo, odr,
 318                                  VAL_PROXY, 1, vhost_cstr);
 319
 320         init_package.request() = init_apdu;
 321         odr_destroy(odr);
 322
 323         init_package.move();  // sending init
 324
 325         if (init_package.session().is_closed())
 326         {
 327             ODR odr = odr_createmem(ODR_ENCODE);
 328             Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 329
 330             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 331             apdu->u.searchResponse->records = rec;
 332             rec->which = Z_Records_NSD;
 333             rec->u.nonSurrogateDiagnostic =
 334                 zget_DefaultDiagFormat(
 335                     odr, YAZ_BIB1_DATABASE_UNAVAILABLE, database.c_str());
 336             package.response() = apdu;
 337
 338             odr_destroy(odr);
 339         }
 340         Z_GDU *gdu = init_package.response().get();
 341         // we hope to get an init response
 342         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 343             Z_APDU_initResponse)
 344         {
 345             if (ODR_MASK_GET(gdu->u.z3950->u.initResponse->options,
 346                              Z_Options_namedResultSets))
 347                 support_named_result_sets = true;
 348         }
 349         else
 350         {
 351             ODR odr = odr_createmem(ODR_ENCODE);
 352             Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 353
 354             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 355             apdu->u.searchResponse->records = rec;
 356             rec->which = Z_Records_NSD;
 357             rec->u.nonSurrogateDiagnostic =
 358                 zget_DefaultDiagFormat(
 359                     odr, YAZ_BIB1_DATABASE_UNAVAILABLE, database.c_str());
 360             package.response() = apdu;
 361
 362             odr_destroy(odr);
 363             return;
 364         }
 365     }
 366     // sending search to backend
 367     Package search_package(id, package.origin());
 368
 369     search_package.copy_filter(package);
 370     const char *sep = strchr(vhost_cstr, '/');
 371     ODR odr = odr_createmem(ODR_ENCODE);
 372     if (sep)
 373         req->databaseNames[0] = odr_strdup(odr, sep+1);
 374
 375     *req->replaceIndicator = 1;
 376
 377     std::string backend_resultSetId = "default";
 378     req->resultSetName = odr_strdup(odr, backend_resultSetId.c_str());
 379     search_package.request() = yazpp_1::GDU(apdu);
 380
 381     odr_destroy(odr);
 382
 383     search_package.move();
 384
 385     if (search_package.session().is_closed())
 386     {
 387         ODR odr = odr_createmem(ODR_ENCODE);
 388         Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 389
 390         Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 391         apdu->u.searchResponse->records = rec;
 392         rec->which = Z_Records_NSD;
 393         rec->u.nonSurrogateDiagnostic =
 394             zget_DefaultDiagFormat(
 395                 odr, YAZ_BIB1_DATABASE_UNAVAILABLE, database.c_str());
 396         package.response() = apdu;
 397
 398         odr_destroy(odr);
 399         return;
 400     }
 401     package.response() = search_package.response();
 402
 403     boost::mutex::scoped_lock lock(m_sessions_mutex);
 404     Ses_it it = m_sessions.find(package.session());
 405     if (it != m_sessions.end())
 406         it->second.m_sets[resultSetId] =
 407             Virt_db_set(id, backend_resultSetId, vhost,
 408                         support_named_result_sets);
 409 }
 410
 411 void yf::Virt_db::Rep::init(Package &package, Z_APDU *apdu, bool &move_later)
 412 {
 413     release_session(package);
 414     boost::mutex::scoped_lock lock(m_sessions_mutex);
 415
 416     Z_InitRequest *req = apdu->u.initRequest;
 417
 418     const char *vhost =
 419         yaz_oi_get_string_oidval(&req->otherInfo, VAL_PROXY, 1, 0);
 420     if (!vhost)
 421     {
 422         ODR odr = odr_createmem(ODR_ENCODE);
 423
 424         Z_APDU *apdu = zget_APDU(odr, Z_APDU_initResponse);
 425         Z_InitResponse *resp = apdu->u.initResponse;
 426
 427         int i;
 428         static const int masks[] = {
 429             Z_Options_search, Z_Options_present, Z_Options_namedResultSets, -1
 430         };
 431         for (i = 0; masks[i] != -1; i++)
 432             if (ODR_MASK_GET(req->options, masks[i]))
 433                 ODR_MASK_SET(resp->options, masks[i]);
 434
 435         static const int versions[] = {
 436             Z_ProtocolVersion_1,
 437             Z_ProtocolVersion_2,
 438             Z_ProtocolVersion_3,
 439             -1
 440         };
 441         for (i = 0; versions[i] != -1; i++)
 442             if (ODR_MASK_GET(req->protocolVersion, versions[i]))
 443                 ODR_MASK_SET(resp->protocolVersion, versions[i]);
 444             else
 445                 break;
 446
 447         package.response() = apdu;
 448
 449         odr_destroy(odr);
 450
 451         m_sessions[package.session()] = Virt_db_session(package.session(), false);
 452     }
 453     else
 454     {
 455         m_sessions[package.session()] = Virt_db_session(package.session(), true);
 456         move_later = true;
 457     }
 458 }
 459
 460 void yf::Virt_db::add_map_db2vhost(std::string db, std::string vhost)
 461 {
 462     m_p->m_maps[db] = Virt_db_map(vhost);
 463 }
 464
 465 void yf::Virt_db::process(Package &package) const
 466 {
 467     Z_GDU *gdu = package.request().get();
 468
 469     if (!gdu || gdu->which != Z_GDU_Z3950)
 470         package.move();
 471     else
 472     {
 473         bool move_later = false;
 474         Z_APDU *apdu = gdu->u.z3950;
 475         if (apdu->which == Z_APDU_initRequest)
 476         {
 477             m_p->init(package, apdu, move_later);
 478         }
 479         else if (apdu->which == Z_APDU_searchRequest)
 480         {
 481             m_p->search(package, apdu, move_later);
 482         }
 483         else if (apdu->which == Z_APDU_presentRequest)
 484         {
 485             m_p->present(package, apdu, move_later);
 486         }
 487         else
 488         {
 489             ODR odr = odr_createmem(ODR_ENCODE);
 490
 491             Z_APDU *apdu = zget_APDU(odr, Z_APDU_close);
 492
 493             *apdu->u.close->closeReason = Z_Close_protocolError;
 494
 495             apdu->u.close->diagnosticInformation =
 496                 odr_strdup(odr, "unsupported APDU in filter_virt_db");
 497
 498             package.response() = apdu;
 499             package.session().close();
 500             odr_destroy(odr);
 501         }
 502         if (move_later)
 503             package.move();
 504     }
 505     if (package.session().is_closed())
 506         m_p->release_session(package);
 507 }
 508
 509
 510 /*
 511  * Local variables:
 512  * c-basic-offset: 4
 513  * indent-tabs-mode: nil
 514  * c-file-style: "stroustrup"
 515  * End:
 516  * vim: shiftwidth=4 tabstop=8 expandtab
 517  */