src/filter_virt_db.cpp

   1 /* $Id: filter_virt_db.cpp,v 1.12 2005-10-30 18:51:20 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/log.h>
  20 #include <yaz/otherinfo.h>
  21 #include <yaz/diagbib1.h>
  22
  23 #include <list>
  24 #include <map>
  25 #include <iostream>
  26
  27 namespace yf = yp2::filter;
  28
  29 namespace yp2 {
  30     namespace filter {
  31         struct Virt_db_set {
  32             Virt_db_set(yp2::Session &id, std::string setname,
  33                         std::string vhost, bool named_result_sets);
  34             Virt_db_set();
  35             ~Virt_db_set();
  36
  37             yp2::Session m_backend_session;
  38             std::string m_backend_setname;
  39             std::string m_vhost;
  40             bool m_named_result_sets;
  41         };
  42         struct Virt_db_session {
  43             Virt_db_session(yp2::Session &id, bool use_vhost);
  44             Virt_db_session();
  45             yp2::Session m_session;
  46             bool m_use_vhost;
  47             std::map<std::string,Virt_db_set> m_sets;
  48         };
  49         struct Virt_db_map {
  50             Virt_db_map(std::string vhost);
  51             Virt_db_map();
  52             std::string m_vhost;
  53         };
  54         class Virt_db::Rep {
  55             friend class Virt_db;
  56
  57             void release_session(Package &package);
  58             void init(Package &package, Z_APDU *apdu, bool &move_later);
  59             void search(Package &package, Z_APDU *apdu, bool &move_later);
  60             void present(Package &package, Z_APDU *apdu, bool &move_later);
  61         private:
  62             boost::mutex m_sessions_mutex;
  63             std::map<yp2::Session,Virt_db_session>m_sessions;
  64             std::map<std::string, Virt_db_map>m_maps;
  65
  66             typedef std::map<yp2::Session,Virt_db_session>::iterator Ses_it;
  67             typedef std::map<std::string,Virt_db_set>::iterator Sets_it;
  68         };
  69     }
  70 }
  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     m_sessions.erase(package.session());
 123 }
 124
 125 void yf::Virt_db::Rep::present(Package &package, Z_APDU *apdu, bool &move_later){
 126     Session *id = 0;
 127     Z_PresentRequest *req = apdu->u.presentRequest;
 128     std::string resultSetId = req->resultSetId;
 129     yp2::odr odr;
 130     {
 131         boost::mutex::scoped_lock lock(m_sessions_mutex);
 132
 133         Ses_it it = m_sessions.find(package.session());
 134         if (it == m_sessions.end())
 135         {
 136             package.response() = odr.create_close(
 137                 Z_Close_protocolError,
 138                 "no session for present request");
 139             package.session().close();
 140             return;
 141         }
 142         if (it->second.m_use_vhost)
 143         {
 144             move_later = true;
 145             return;
 146         }
 147         Sets_it sets_it = it->second.m_sets.find(resultSetId);
 148         if (sets_it == it->second.m_sets.end())
 149         {
 150             Z_APDU *apdu = zget_APDU(odr, Z_APDU_presentResponse);
 151
 152             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 153             apdu->u.presentResponse->records = rec;
 154             rec->which = Z_Records_NSD;
 155             rec->u.nonSurrogateDiagnostic =
 156                 zget_DefaultDiagFormat(
 157                     odr,
 158                     YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST,
 159                     resultSetId.c_str());
 160             package.response() = apdu;
 161
 162             return;
 163         }
 164         id = new yp2::Session(sets_it->second.m_backend_session);
 165     }
 166
 167     // sending present to backend
 168     Package present_package(*id, package.origin());
 169     present_package.copy_filter(package);
 170
 171     req->resultSetId = odr_strdup(odr, "default");
 172     present_package.request() = yazpp_1::GDU(apdu);
 173
 174     present_package.move();
 175
 176     if (present_package.session().is_closed())
 177     {
 178         Z_APDU *apdu = zget_APDU(odr, Z_APDU_presentResponse);
 179
 180         Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 181         apdu->u.presentResponse->records = rec;
 182         rec->which = Z_Records_NSD;
 183         rec->u.nonSurrogateDiagnostic =
 184             zget_DefaultDiagFormat(
 185                 odr,
 186                 YAZ_BIB1_RESULT_SET_NO_LONGER_EXISTS_UNILATERALLY_DELETED_BY_,
 187                 resultSetId.c_str());
 188         package.response() = apdu;
 189
 190         boost::mutex::scoped_lock lock(m_sessions_mutex);
 191         Ses_it it = m_sessions.find(package.session());
 192         if (it != m_sessions.end())
 193             it->second.m_sets.erase(resultSetId);
 194     }
 195     else
 196     {
 197         package.response() = present_package.response();
 198     }
 199     delete id;
 200 }
 201
 202 void yf::Virt_db::Rep::search(Package &package, Z_APDU *apdu, bool &move_later)
 203 {
 204     Z_SearchRequest *req = apdu->u.searchRequest;
 205     std::string vhost;
 206     std::string database;
 207     std::string resultSetId = req->resultSetName;
 208     bool support_named_result_sets = false;  // whether backend supports it
 209     yp2::odr odr;
 210     {
 211         boost::mutex::scoped_lock lock(m_sessions_mutex);
 212
 213         Ses_it it = m_sessions.find(package.session());
 214         if (it == m_sessions.end())
 215         {
 216             package.response() = odr.create_close(
 217                 Z_Close_protocolError,
 218                 "no session for search request");
 219             package.session().close();
 220
 221             return;
 222         }
 223         if (it->second.m_use_vhost)
 224         {
 225             move_later = true;
 226             return;
 227         }
 228         if (req->num_databaseNames != 1)
 229         {   // exactly one database must be specified
 230             Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 231
 232             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 233             apdu->u.searchResponse->records = rec;
 234             rec->which = Z_Records_NSD;
 235             rec->u.nonSurrogateDiagnostic =
 236                 zget_DefaultDiagFormat(
 237                     odr, YAZ_BIB1_TOO_MANY_DATABASES_SPECIFIED, 0);
 238             package.response() = apdu;
 239
 240             return;
 241         }
 242         database = req->databaseNames[0];
 243         std::map<std::string, Virt_db_map>::iterator map_it;
 244         map_it = m_maps.find(database);
 245         if (map_it == m_maps.end())
 246         {   // no map for database: return diagnostic
 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_DATABASE_DOES_NOT_EXIST, database.c_str());
 255             package.response() = apdu;
 256
 257             return;
 258         }
 259         if (*req->replaceIndicator == 0)
 260         {
 261             Sets_it sets_it = it->second.m_sets.find(req->resultSetName);
 262             if (sets_it != it->second.m_sets.end())
 263             {
 264                 Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 265
 266                 Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 267                 apdu->u.searchResponse->records = rec;
 268                 rec->which = Z_Records_NSD;
 269                 rec->u.nonSurrogateDiagnostic =
 270                     zget_DefaultDiagFormat(
 271                         odr,
 272                         YAZ_BIB1_RESULT_SET_EXISTS_AND_REPLACE_INDICATOR_OFF,
 273                         0);
 274                 package.response() = apdu;
 275
 276                 return;
 277             }
 278         }
 279         it->second.m_sets.erase(req->resultSetName);
 280         vhost = map_it->second.m_vhost;
 281     }
 282     // we might look for an existing session with same vhost
 283     Session id;
 284     const char *vhost_cstr = vhost.c_str();
 285     if (true)
 286     {  // sending init to backend
 287         Package init_package(id, package.origin());
 288         init_package.copy_filter(package);
 289
 290         Z_APDU *init_apdu = zget_APDU(odr, Z_APDU_initRequest);
 291
 292         yaz_oi_set_string_oidval(&init_apdu->u.initRequest->otherInfo, odr,
 293                                  VAL_PROXY, 1, vhost_cstr);
 294
 295         init_package.request() = init_apdu;
 296
 297         init_package.move();  // sending init
 298
 299         if (init_package.session().is_closed())
 300         {
 301             Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 302
 303             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 304             apdu->u.searchResponse->records = rec;
 305             rec->which = Z_Records_NSD;
 306             rec->u.nonSurrogateDiagnostic =
 307                 zget_DefaultDiagFormat(
 308                     odr, YAZ_BIB1_DATABASE_UNAVAILABLE, database.c_str());
 309             package.response() = apdu;
 310         }
 311         Z_GDU *gdu = init_package.response().get();
 312         // we hope to get an init response
 313         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 314             Z_APDU_initResponse)
 315         {
 316             if (ODR_MASK_GET(gdu->u.z3950->u.initResponse->options,
 317                              Z_Options_namedResultSets))
 318                 support_named_result_sets = true;
 319         }
 320         else
 321         {
 322             Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 323
 324             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 325             apdu->u.searchResponse->records = rec;
 326             rec->which = Z_Records_NSD;
 327             rec->u.nonSurrogateDiagnostic =
 328                 zget_DefaultDiagFormat(
 329                     odr, YAZ_BIB1_DATABASE_UNAVAILABLE, database.c_str());
 330             package.response() = apdu;
 331
 332             return;
 333         }
 334     }
 335     // sending search to backend
 336     Package search_package(id, package.origin());
 337
 338     search_package.copy_filter(package);
 339     const char *sep = strchr(vhost_cstr, '/');
 340     if (sep)
 341         req->databaseNames[0] = odr_strdup(odr, sep+1);
 342
 343     *req->replaceIndicator = 1;
 344
 345     std::string backend_resultSetId = "default";
 346     req->resultSetName = odr_strdup(odr, backend_resultSetId.c_str());
 347     search_package.request() = yazpp_1::GDU(apdu);
 348
 349     search_package.move();
 350
 351     if (search_package.session().is_closed())
 352     {
 353         Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 354
 355         Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 356         apdu->u.searchResponse->records = rec;
 357         rec->which = Z_Records_NSD;
 358         rec->u.nonSurrogateDiagnostic =
 359             zget_DefaultDiagFormat(
 360                 odr, YAZ_BIB1_DATABASE_UNAVAILABLE, database.c_str());
 361         package.response() = apdu;
 362
 363         return;
 364     }
 365     package.response() = search_package.response();
 366
 367     boost::mutex::scoped_lock lock(m_sessions_mutex);
 368     Ses_it it = m_sessions.find(package.session());
 369     if (it != m_sessions.end())
 370         it->second.m_sets[resultSetId] =
 371             Virt_db_set(id, backend_resultSetId, vhost,
 372                         support_named_result_sets);
 373 }
 374
 375 void yf::Virt_db::Rep::init(Package &package, Z_APDU *apdu, bool &move_later)
 376 {
 377     release_session(package);
 378     boost::mutex::scoped_lock lock(m_sessions_mutex);
 379
 380     Z_InitRequest *req = apdu->u.initRequest;
 381
 382     const char *vhost =
 383         yaz_oi_get_string_oidval(&req->otherInfo, VAL_PROXY, 1, 0);
 384     if (!vhost)
 385     {
 386         yp2::odr odr;
 387         Z_APDU *apdu = zget_APDU(odr, Z_APDU_initResponse);
 388         Z_InitResponse *resp = apdu->u.initResponse;
 389
 390         int i;
 391         static const int masks[] = {
 392             Z_Options_search, Z_Options_present, Z_Options_namedResultSets, -1
 393         };
 394         for (i = 0; masks[i] != -1; i++)
 395             if (ODR_MASK_GET(req->options, masks[i]))
 396                 ODR_MASK_SET(resp->options, masks[i]);
 397
 398         static const int versions[] = {
 399             Z_ProtocolVersion_1,
 400             Z_ProtocolVersion_2,
 401             Z_ProtocolVersion_3,
 402             -1
 403         };
 404         for (i = 0; versions[i] != -1; i++)
 405             if (ODR_MASK_GET(req->protocolVersion, versions[i]))
 406                 ODR_MASK_SET(resp->protocolVersion, versions[i]);
 407             else
 408                 break;
 409
 410         package.response() = apdu;
 411
 412         m_sessions[package.session()] = Virt_db_session(package.session(), false);
 413     }
 414     else
 415     {
 416         m_sessions[package.session()] = Virt_db_session(package.session(), true);
 417         move_later = true;
 418     }
 419 }
 420
 421 void yf::Virt_db::add_map_db2vhost(std::string db, std::string vhost)
 422 {
 423     m_p->m_maps[db] = Virt_db_map(vhost);
 424 }
 425
 426 void yf::Virt_db::process(Package &package) const
 427 {
 428     Z_GDU *gdu = package.request().get();
 429
 430     if (!gdu || gdu->which != Z_GDU_Z3950)
 431         package.move();
 432     else
 433     {
 434         bool move_later = false;
 435         Z_APDU *apdu = gdu->u.z3950;
 436         if (apdu->which == Z_APDU_initRequest)
 437         {
 438             m_p->init(package, apdu, move_later);
 439         }
 440         else if (apdu->which == Z_APDU_searchRequest)
 441         {
 442             m_p->search(package, apdu, move_later);
 443         }
 444         else if (apdu->which == Z_APDU_presentRequest)
 445         {
 446             m_p->present(package, apdu, move_later);
 447         }
 448         else
 449         {
 450             yp2::odr odr;
 451
 452             package.response() = odr.create_close(
 453                 Z_Close_protocolError,
 454                 "unsupported APDU in filter_virt_db");
 455
 456             package.session().close();
 457         }
 458         if (move_later)
 459             package.move();
 460     }
 461     if (package.session().is_closed())
 462         m_p->release_session(package);
 463 }
 464
 465
 466 /*
 467  * Local variables:
 468  * c-basic-offset: 4
 469  * indent-tabs-mode: nil
 470  * c-file-style: "stroustrup"
 471  * End:
 472  * vim: shiftwidth=4 tabstop=8 expandtab
 473  */