src/filter_virt_db.cpp

   1 /* $Id: filter_virt_db.cpp,v 1.15 2005-12-19 08:42:59 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 "util.hpp"
  16 #include "filter_virt_db.hpp"
  17
  18 #include <yaz/zgdu.h>
  19 #include <yaz/otherinfo.h>
  20 #include <yaz/diagbib1.h>
  21
  22 #include <map>
  23 #include <iostream>
  24
  25 namespace yf = yp2::filter;
  26
  27 namespace yp2 {
  28     namespace filter {
  29         struct Virt_db_set {
  30             Virt_db_set(yp2::Session &id, std::string setname,
  31                         std::string vhost, bool named_result_sets);
  32             Virt_db_set();
  33             ~Virt_db_set();
  34
  35             yp2::Session m_backend_session;
  36             std::string m_backend_setname;
  37             std::string m_vhost;
  38             bool m_named_result_sets;
  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 using namespace yp2;
  71
  72 yf::Virt_db_set::Virt_db_set(yp2::Session &id, std::string setname,
  73                              std::string vhost, bool named_result_sets)
  74     :   m_backend_session(id), m_backend_setname(setname), m_vhost(vhost),
  75         m_named_result_sets(named_result_sets)
  76 {
  77 }
  78
  79
  80 yf::Virt_db_set::Virt_db_set()
  81 {
  82 }
  83
  84
  85 yf::Virt_db_set::~Virt_db_set()
  86 {
  87 }
  88
  89 yf::Virt_db_map::Virt_db_map(std::string vhost)
  90     : m_vhost(vhost)
  91 {
  92 }
  93
  94 yf::Virt_db_map::Virt_db_map()
  95 {
  96 }
  97
  98 yf::Virt_db_session::Virt_db_session()
  99     : m_use_vhost(false)
 100 {
 101
 102 }
 103
 104 yf::Virt_db_session::Virt_db_session(yp2::Session &id,
 105                                      bool use_vhost) :
 106     m_session(id) , m_use_vhost(use_vhost)
 107 {
 108
 109 }
 110
 111 yf::Virt_db::Virt_db() : m_p(new Virt_db::Rep)
 112 {
 113 }
 114
 115 yf::Virt_db::~Virt_db() {
 116 }
 117
 118 void yf::Virt_db::Rep::release_session(Package &package)
 119 {
 120     boost::mutex::scoped_lock lock(m_sessions_mutex);
 121
 122     Ses_it it = m_sessions.find(package.session());
 123
 124     if (it != m_sessions.end())
 125     {
 126         Sets_it sit = it->second.m_sets.begin();
 127         for (; sit != it->second.m_sets.end(); sit++)
 128         {
 129             sit->second.m_backend_session.close();
 130             Package close_package(sit->second.m_backend_session, package.origin());
 131             close_package.copy_filter(package);
 132
 133             close_package.move();
 134         }
 135     }
 136     m_sessions.erase(package.session());
 137 }
 138
 139 void yf::Virt_db::Rep::present(Package &package, Z_APDU *apdu, bool &move_later){
 140     Session *id = 0;
 141     Z_PresentRequest *req = apdu->u.presentRequest;
 142     std::string resultSetId = req->resultSetId;
 143     yp2::odr odr;
 144     {
 145         boost::mutex::scoped_lock lock(m_sessions_mutex);
 146
 147         Ses_it it = m_sessions.find(package.session());
 148         if (it == m_sessions.end())
 149         {
 150             package.response() = odr.create_close(
 151                 Z_Close_protocolError,
 152                 "no session for present request");
 153             package.session().close();
 154             return;
 155         }
 156         if (it->second.m_use_vhost)
 157         {
 158             move_later = true;
 159             return;
 160         }
 161         Sets_it sets_it = it->second.m_sets.find(resultSetId);
 162         if (sets_it == it->second.m_sets.end())
 163         {
 164             Z_APDU *apdu = zget_APDU(odr, Z_APDU_presentResponse);
 165
 166             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 167             apdu->u.presentResponse->records = rec;
 168             rec->which = Z_Records_NSD;
 169             rec->u.nonSurrogateDiagnostic =
 170                 zget_DefaultDiagFormat(
 171                     odr,
 172                     YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST,
 173                     resultSetId.c_str());
 174             package.response() = apdu;
 175
 176             return;
 177         }
 178         id = new yp2::Session(sets_it->second.m_backend_session);
 179     }
 180
 181     // sending present to backend
 182     Package present_package(*id, package.origin());
 183     present_package.copy_filter(package);
 184
 185     req->resultSetId = odr_strdup(odr, "default");
 186     present_package.request() = yazpp_1::GDU(apdu);
 187
 188     present_package.move();
 189
 190     if (present_package.session().is_closed())
 191     {
 192         Z_APDU *apdu = zget_APDU(odr, Z_APDU_presentResponse);
 193
 194         Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 195         apdu->u.presentResponse->records = rec;
 196         rec->which = Z_Records_NSD;
 197         rec->u.nonSurrogateDiagnostic =
 198             zget_DefaultDiagFormat(
 199                 odr,
 200                 YAZ_BIB1_RESULT_SET_NO_LONGER_EXISTS_UNILATERALLY_DELETED_BY_,
 201                 resultSetId.c_str());
 202         package.response() = apdu;
 203
 204         boost::mutex::scoped_lock lock(m_sessions_mutex);
 205         Ses_it it = m_sessions.find(package.session());
 206         if (it != m_sessions.end())
 207             it->second.m_sets.erase(resultSetId);
 208     }
 209     else
 210     {
 211         package.response() = present_package.response();
 212     }
 213     delete id;
 214 }
 215
 216 void yf::Virt_db::Rep::search(Package &package, Z_APDU *apdu, bool &move_later)
 217 {
 218     Z_SearchRequest *req = apdu->u.searchRequest;
 219     std::string vhost;
 220     std::string database;
 221     std::string resultSetId = req->resultSetName;
 222     bool support_named_result_sets = false;  // whether backend supports it
 223     yp2::odr odr;
 224     {
 225         boost::mutex::scoped_lock lock(m_sessions_mutex);
 226
 227         Ses_it it = m_sessions.find(package.session());
 228         if (it == m_sessions.end())
 229         {
 230             package.response() = odr.create_close(
 231                 Z_Close_protocolError,
 232                 "no session for search request");
 233             package.session().close();
 234
 235             return;
 236         }
 237         if (it->second.m_use_vhost)
 238         {
 239             move_later = true;
 240             return;
 241         }
 242         if (req->num_databaseNames != 1)
 243         {   // exactly one database must be specified
 244             Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 245
 246             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 247             apdu->u.searchResponse->records = rec;
 248             rec->which = Z_Records_NSD;
 249             rec->u.nonSurrogateDiagnostic =
 250                 zget_DefaultDiagFormat(
 251                     odr, YAZ_BIB1_TOO_MANY_DATABASES_SPECIFIED, 0);
 252             package.response() = apdu;
 253
 254             return;
 255         }
 256         database = req->databaseNames[0];
 257         std::map<std::string, Virt_db_map>::iterator map_it;
 258         map_it = m_maps.find(database);
 259         if (map_it == m_maps.end())
 260         {   // no map for database: return diagnostic
 261             Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 262
 263             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 264             apdu->u.searchResponse->records = rec;
 265             rec->which = Z_Records_NSD;
 266             rec->u.nonSurrogateDiagnostic =
 267                 zget_DefaultDiagFormat(
 268                     odr, YAZ_BIB1_DATABASE_DOES_NOT_EXIST, database.c_str());
 269             package.response() = apdu;
 270
 271             return;
 272         }
 273         if (*req->replaceIndicator == 0)
 274         {
 275             Sets_it sets_it = it->second.m_sets.find(req->resultSetName);
 276             if (sets_it != it->second.m_sets.end())
 277             {
 278                 Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 279
 280                 Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 281                 apdu->u.searchResponse->records = rec;
 282                 rec->which = Z_Records_NSD;
 283                 rec->u.nonSurrogateDiagnostic =
 284                     zget_DefaultDiagFormat(
 285                         odr,
 286                         YAZ_BIB1_RESULT_SET_EXISTS_AND_REPLACE_INDICATOR_OFF,
 287                         0);
 288                 package.response() = apdu;
 289
 290                 return;
 291             }
 292         }
 293         it->second.m_sets.erase(req->resultSetName);
 294         vhost = map_it->second.m_vhost;
 295     }
 296     // we might look for an existing session with same vhost
 297     Session id;
 298     const char *vhost_cstr = vhost.c_str();
 299     if (true)
 300     {  // sending init to backend
 301         Package init_package(id, package.origin());
 302         init_package.copy_filter(package);
 303
 304         Z_APDU *init_apdu = zget_APDU(odr, Z_APDU_initRequest);
 305
 306         yaz_oi_set_string_oidval(&init_apdu->u.initRequest->otherInfo, odr,
 307                                  VAL_PROXY, 1, vhost_cstr);
 308
 309         init_package.request() = init_apdu;
 310
 311         init_package.move();  // sending init
 312
 313         if (init_package.session().is_closed())
 314         {
 315             Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 316
 317             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 318             apdu->u.searchResponse->records = rec;
 319             rec->which = Z_Records_NSD;
 320             rec->u.nonSurrogateDiagnostic =
 321                 zget_DefaultDiagFormat(
 322                     odr, YAZ_BIB1_DATABASE_UNAVAILABLE, database.c_str());
 323             package.response() = apdu;
 324         }
 325         Z_GDU *gdu = init_package.response().get();
 326         // we hope to get an init response
 327         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 328             Z_APDU_initResponse)
 329         {
 330             if (ODR_MASK_GET(gdu->u.z3950->u.initResponse->options,
 331                              Z_Options_namedResultSets))
 332                 support_named_result_sets = true;
 333         }
 334         else
 335         {
 336             Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 337
 338             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 339             apdu->u.searchResponse->records = rec;
 340             rec->which = Z_Records_NSD;
 341             rec->u.nonSurrogateDiagnostic =
 342                 zget_DefaultDiagFormat(
 343                     odr, YAZ_BIB1_DATABASE_UNAVAILABLE, database.c_str());
 344             package.response() = apdu;
 345
 346             return;
 347         }
 348     }
 349     // sending search to backend
 350     Package search_package(id, package.origin());
 351
 352     search_package.copy_filter(package);
 353     const char *sep = strchr(vhost_cstr, '/');
 354     if (sep)
 355         req->databaseNames[0] = odr_strdup(odr, sep+1);
 356
 357     *req->replaceIndicator = 1;
 358
 359     std::string backend_resultSetId = "default";
 360     req->resultSetName = odr_strdup(odr, backend_resultSetId.c_str());
 361     search_package.request() = yazpp_1::GDU(apdu);
 362
 363     search_package.move();
 364
 365     if (search_package.session().is_closed())
 366     {
 367         Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 368
 369         Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 370         apdu->u.searchResponse->records = rec;
 371         rec->which = Z_Records_NSD;
 372         rec->u.nonSurrogateDiagnostic =
 373             zget_DefaultDiagFormat(
 374                 odr, YAZ_BIB1_DATABASE_UNAVAILABLE, database.c_str());
 375         package.response() = apdu;
 376
 377         return;
 378     }
 379     package.response() = search_package.response();
 380
 381     boost::mutex::scoped_lock lock(m_sessions_mutex);
 382     Ses_it it = m_sessions.find(package.session());
 383     if (it != m_sessions.end())
 384         it->second.m_sets[resultSetId] =
 385             Virt_db_set(id, backend_resultSetId, vhost,
 386                         support_named_result_sets);
 387 }
 388
 389 void yf::Virt_db::Rep::init(Package &package, Z_APDU *apdu, bool &move_later)
 390 {
 391     release_session(package);
 392     boost::mutex::scoped_lock lock(m_sessions_mutex);
 393
 394     Z_InitRequest *req = apdu->u.initRequest;
 395
 396     const char *vhost =
 397         yaz_oi_get_string_oidval(&req->otherInfo, VAL_PROXY, 1, 0);
 398     if (!vhost)
 399     {
 400         yp2::odr odr;
 401         Z_APDU *apdu = zget_APDU(odr, Z_APDU_initResponse);
 402         Z_InitResponse *resp = apdu->u.initResponse;
 403
 404         int i;
 405         static const int masks[] = {
 406             Z_Options_search, Z_Options_present, Z_Options_namedResultSets, -1
 407         };
 408         for (i = 0; masks[i] != -1; i++)
 409             if (ODR_MASK_GET(req->options, masks[i]))
 410                 ODR_MASK_SET(resp->options, masks[i]);
 411
 412         static const int versions[] = {
 413             Z_ProtocolVersion_1,
 414             Z_ProtocolVersion_2,
 415             Z_ProtocolVersion_3,
 416             -1
 417         };
 418         for (i = 0; versions[i] != -1; i++)
 419             if (ODR_MASK_GET(req->protocolVersion, versions[i]))
 420                 ODR_MASK_SET(resp->protocolVersion, versions[i]);
 421             else
 422                 break;
 423
 424         package.response() = apdu;
 425
 426         m_sessions[package.session()] = Virt_db_session(package.session(), false);
 427     }
 428     else
 429     {
 430         m_sessions[package.session()] = Virt_db_session(package.session(), true);
 431         move_later = true;
 432     }
 433 }
 434
 435 void yf::Virt_db::add_map_db2vhost(std::string db, std::string vhost)
 436 {
 437     m_p->m_maps[db] = Virt_db_map(vhost);
 438 }
 439
 440 void yf::Virt_db::process(Package &package) const
 441 {
 442     Z_GDU *gdu = package.request().get();
 443
 444     if (package.session().is_closed())
 445         m_p->release_session(package);
 446     else if (!gdu || gdu->which != Z_GDU_Z3950)
 447         package.move();
 448     else
 449     {
 450         bool move_later = false;
 451         Z_APDU *apdu = gdu->u.z3950;
 452         if (apdu->which == Z_APDU_initRequest)
 453         {
 454             m_p->init(package, apdu, move_later);
 455         }
 456         else if (apdu->which == Z_APDU_searchRequest)
 457         {
 458             m_p->search(package, apdu, move_later);
 459         }
 460         else if (apdu->which == Z_APDU_presentRequest)
 461         {
 462             m_p->present(package, apdu, move_later);
 463         }
 464         else if (apdu->which == Z_APDU_close)
 465         {
 466             package.session().close();
 467             m_p->release_session(package);
 468         }
 469         else
 470         {
 471             yp2::odr odr;
 472
 473             package.response() = odr.create_close(
 474                 Z_Close_protocolError,
 475                 "unsupported APDU in filter_virt_db");
 476
 477             package.session().close();
 478             m_p->release_session(package);
 479         }
 480         if (move_later)
 481             package.move();
 482     }
 483 }
 484
 485
 486 /*
 487  * Local variables:
 488  * c-basic-offset: 4
 489  * indent-tabs-mode: nil
 490  * c-file-style: "stroustrup"
 491  * End:
 492  * vim: shiftwidth=4 tabstop=8 expandtab
 493  */