src/filter_virt_db.cpp

   1 /* $Id: filter_virt_db.cpp,v 1.13 2005-11-03 14:45:16 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 using namespace yp2;
  73
  74 yf::Virt_db_set::Virt_db_set(yp2::Session &id, std::string setname,
  75                              std::string vhost, bool named_result_sets)
  76     :   m_backend_session(id), m_backend_setname(setname), m_vhost(vhost),
  77         m_named_result_sets(named_result_sets)
  78 {
  79 }
  80
  81
  82 yf::Virt_db_set::Virt_db_set()
  83 {
  84 }
  85
  86
  87 yf::Virt_db_set::~Virt_db_set()
  88 {
  89 }
  90
  91 yf::Virt_db_map::Virt_db_map(std::string vhost)
  92     : m_vhost(vhost)
  93 {
  94 }
  95
  96 yf::Virt_db_map::Virt_db_map()
  97 {
  98 }
  99
 100 yf::Virt_db_session::Virt_db_session()
 101     : m_use_vhost(false)
 102 {
 103
 104 }
 105
 106 yf::Virt_db_session::Virt_db_session(yp2::Session &id,
 107                                      bool use_vhost) :
 108     m_session(id) , m_use_vhost(use_vhost)
 109 {
 110
 111 }
 112
 113 yf::Virt_db::Virt_db() : m_p(new Virt_db::Rep)
 114 {
 115 }
 116
 117 yf::Virt_db::~Virt_db() {
 118 }
 119
 120 void yf::Virt_db::Rep::release_session(Package &package)
 121 {
 122     boost::mutex::scoped_lock lock(m_sessions_mutex);
 123
 124     m_sessions.erase(package.session());
 125 }
 126
 127 void yf::Virt_db::Rep::present(Package &package, Z_APDU *apdu, bool &move_later){
 128     Session *id = 0;
 129     Z_PresentRequest *req = apdu->u.presentRequest;
 130     std::string resultSetId = req->resultSetId;
 131     yp2::odr odr;
 132     {
 133         boost::mutex::scoped_lock lock(m_sessions_mutex);
 134
 135         Ses_it it = m_sessions.find(package.session());
 136         if (it == m_sessions.end())
 137         {
 138             package.response() = odr.create_close(
 139                 Z_Close_protocolError,
 140                 "no session for present request");
 141             package.session().close();
 142             return;
 143         }
 144         if (it->second.m_use_vhost)
 145         {
 146             move_later = true;
 147             return;
 148         }
 149         Sets_it sets_it = it->second.m_sets.find(resultSetId);
 150         if (sets_it == it->second.m_sets.end())
 151         {
 152             Z_APDU *apdu = zget_APDU(odr, Z_APDU_presentResponse);
 153
 154             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 155             apdu->u.presentResponse->records = rec;
 156             rec->which = Z_Records_NSD;
 157             rec->u.nonSurrogateDiagnostic =
 158                 zget_DefaultDiagFormat(
 159                     odr,
 160                     YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST,
 161                     resultSetId.c_str());
 162             package.response() = apdu;
 163
 164             return;
 165         }
 166         id = new yp2::Session(sets_it->second.m_backend_session);
 167     }
 168
 169     // sending present to backend
 170     Package present_package(*id, package.origin());
 171     present_package.copy_filter(package);
 172
 173     req->resultSetId = odr_strdup(odr, "default");
 174     present_package.request() = yazpp_1::GDU(apdu);
 175
 176     present_package.move();
 177
 178     if (present_package.session().is_closed())
 179     {
 180         Z_APDU *apdu = zget_APDU(odr, Z_APDU_presentResponse);
 181
 182         Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 183         apdu->u.presentResponse->records = rec;
 184         rec->which = Z_Records_NSD;
 185         rec->u.nonSurrogateDiagnostic =
 186             zget_DefaultDiagFormat(
 187                 odr,
 188                 YAZ_BIB1_RESULT_SET_NO_LONGER_EXISTS_UNILATERALLY_DELETED_BY_,
 189                 resultSetId.c_str());
 190         package.response() = apdu;
 191
 192         boost::mutex::scoped_lock lock(m_sessions_mutex);
 193         Ses_it it = m_sessions.find(package.session());
 194         if (it != m_sessions.end())
 195             it->second.m_sets.erase(resultSetId);
 196     }
 197     else
 198     {
 199         package.response() = present_package.response();
 200     }
 201     delete id;
 202 }
 203
 204 void yf::Virt_db::Rep::search(Package &package, Z_APDU *apdu, bool &move_later)
 205 {
 206     Z_SearchRequest *req = apdu->u.searchRequest;
 207     std::string vhost;
 208     std::string database;
 209     std::string resultSetId = req->resultSetName;
 210     bool support_named_result_sets = false;  // whether backend supports it
 211     yp2::odr odr;
 212     {
 213         boost::mutex::scoped_lock lock(m_sessions_mutex);
 214
 215         Ses_it it = m_sessions.find(package.session());
 216         if (it == m_sessions.end())
 217         {
 218             package.response() = odr.create_close(
 219                 Z_Close_protocolError,
 220                 "no session for search request");
 221             package.session().close();
 222
 223             return;
 224         }
 225         if (it->second.m_use_vhost)
 226         {
 227             move_later = true;
 228             return;
 229         }
 230         if (req->num_databaseNames != 1)
 231         {   // exactly one database must be specified
 232             Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 233
 234             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 235             apdu->u.searchResponse->records = rec;
 236             rec->which = Z_Records_NSD;
 237             rec->u.nonSurrogateDiagnostic =
 238                 zget_DefaultDiagFormat(
 239                     odr, YAZ_BIB1_TOO_MANY_DATABASES_SPECIFIED, 0);
 240             package.response() = apdu;
 241
 242             return;
 243         }
 244         database = req->databaseNames[0];
 245         std::map<std::string, Virt_db_map>::iterator map_it;
 246         map_it = m_maps.find(database);
 247         if (map_it == m_maps.end())
 248         {   // no map for database: return diagnostic
 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_DATABASE_DOES_NOT_EXIST, database.c_str());
 257             package.response() = apdu;
 258
 259             return;
 260         }
 261         if (*req->replaceIndicator == 0)
 262         {
 263             Sets_it sets_it = it->second.m_sets.find(req->resultSetName);
 264             if (sets_it != it->second.m_sets.end())
 265             {
 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,
 274                         YAZ_BIB1_RESULT_SET_EXISTS_AND_REPLACE_INDICATOR_OFF,
 275                         0);
 276                 package.response() = apdu;
 277
 278                 return;
 279             }
 280         }
 281         it->second.m_sets.erase(req->resultSetName);
 282         vhost = map_it->second.m_vhost;
 283     }
 284     // we might look for an existing session with same vhost
 285     Session id;
 286     const char *vhost_cstr = vhost.c_str();
 287     if (true)
 288     {  // sending init to backend
 289         Package init_package(id, package.origin());
 290         init_package.copy_filter(package);
 291
 292         Z_APDU *init_apdu = zget_APDU(odr, Z_APDU_initRequest);
 293
 294         yaz_oi_set_string_oidval(&init_apdu->u.initRequest->otherInfo, odr,
 295                                  VAL_PROXY, 1, vhost_cstr);
 296
 297         init_package.request() = init_apdu;
 298
 299         init_package.move();  // sending init
 300
 301         if (init_package.session().is_closed())
 302         {
 303             Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 304
 305             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 306             apdu->u.searchResponse->records = rec;
 307             rec->which = Z_Records_NSD;
 308             rec->u.nonSurrogateDiagnostic =
 309                 zget_DefaultDiagFormat(
 310                     odr, YAZ_BIB1_DATABASE_UNAVAILABLE, database.c_str());
 311             package.response() = apdu;
 312         }
 313         Z_GDU *gdu = init_package.response().get();
 314         // we hope to get an init response
 315         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 316             Z_APDU_initResponse)
 317         {
 318             if (ODR_MASK_GET(gdu->u.z3950->u.initResponse->options,
 319                              Z_Options_namedResultSets))
 320                 support_named_result_sets = true;
 321         }
 322         else
 323         {
 324             Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 325
 326             Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 327             apdu->u.searchResponse->records = rec;
 328             rec->which = Z_Records_NSD;
 329             rec->u.nonSurrogateDiagnostic =
 330                 zget_DefaultDiagFormat(
 331                     odr, YAZ_BIB1_DATABASE_UNAVAILABLE, database.c_str());
 332             package.response() = apdu;
 333
 334             return;
 335         }
 336     }
 337     // sending search to backend
 338     Package search_package(id, package.origin());
 339
 340     search_package.copy_filter(package);
 341     const char *sep = strchr(vhost_cstr, '/');
 342     if (sep)
 343         req->databaseNames[0] = odr_strdup(odr, sep+1);
 344
 345     *req->replaceIndicator = 1;
 346
 347     std::string backend_resultSetId = "default";
 348     req->resultSetName = odr_strdup(odr, backend_resultSetId.c_str());
 349     search_package.request() = yazpp_1::GDU(apdu);
 350
 351     search_package.move();
 352
 353     if (search_package.session().is_closed())
 354     {
 355         Z_APDU *apdu = zget_APDU(odr, Z_APDU_searchResponse);
 356
 357         Z_Records *rec = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 358         apdu->u.searchResponse->records = rec;
 359         rec->which = Z_Records_NSD;
 360         rec->u.nonSurrogateDiagnostic =
 361             zget_DefaultDiagFormat(
 362                 odr, YAZ_BIB1_DATABASE_UNAVAILABLE, database.c_str());
 363         package.response() = apdu;
 364
 365         return;
 366     }
 367     package.response() = search_package.response();
 368
 369     boost::mutex::scoped_lock lock(m_sessions_mutex);
 370     Ses_it it = m_sessions.find(package.session());
 371     if (it != m_sessions.end())
 372         it->second.m_sets[resultSetId] =
 373             Virt_db_set(id, backend_resultSetId, vhost,
 374                         support_named_result_sets);
 375 }
 376
 377 void yf::Virt_db::Rep::init(Package &package, Z_APDU *apdu, bool &move_later)
 378 {
 379     release_session(package);
 380     boost::mutex::scoped_lock lock(m_sessions_mutex);
 381
 382     Z_InitRequest *req = apdu->u.initRequest;
 383
 384     const char *vhost =
 385         yaz_oi_get_string_oidval(&req->otherInfo, VAL_PROXY, 1, 0);
 386     if (!vhost)
 387     {
 388         yp2::odr odr;
 389         Z_APDU *apdu = zget_APDU(odr, Z_APDU_initResponse);
 390         Z_InitResponse *resp = apdu->u.initResponse;
 391
 392         int i;
 393         static const int masks[] = {
 394             Z_Options_search, Z_Options_present, Z_Options_namedResultSets, -1
 395         };
 396         for (i = 0; masks[i] != -1; i++)
 397             if (ODR_MASK_GET(req->options, masks[i]))
 398                 ODR_MASK_SET(resp->options, masks[i]);
 399
 400         static const int versions[] = {
 401             Z_ProtocolVersion_1,
 402             Z_ProtocolVersion_2,
 403             Z_ProtocolVersion_3,
 404             -1
 405         };
 406         for (i = 0; versions[i] != -1; i++)
 407             if (ODR_MASK_GET(req->protocolVersion, versions[i]))
 408                 ODR_MASK_SET(resp->protocolVersion, versions[i]);
 409             else
 410                 break;
 411
 412         package.response() = apdu;
 413
 414         m_sessions[package.session()] = Virt_db_session(package.session(), false);
 415     }
 416     else
 417     {
 418         m_sessions[package.session()] = Virt_db_session(package.session(), true);
 419         move_later = true;
 420     }
 421 }
 422
 423 void yf::Virt_db::add_map_db2vhost(std::string db, std::string vhost)
 424 {
 425     m_p->m_maps[db] = Virt_db_map(vhost);
 426 }
 427
 428 void yf::Virt_db::process(Package &package) const
 429 {
 430     Z_GDU *gdu = package.request().get();
 431
 432     if (!gdu || gdu->which != Z_GDU_Z3950)
 433         package.move();
 434     else
 435     {
 436         bool move_later = false;
 437         Z_APDU *apdu = gdu->u.z3950;
 438         if (apdu->which == Z_APDU_initRequest)
 439         {
 440             m_p->init(package, apdu, move_later);
 441         }
 442         else if (apdu->which == Z_APDU_searchRequest)
 443         {
 444             m_p->search(package, apdu, move_later);
 445         }
 446         else if (apdu->which == Z_APDU_presentRequest)
 447         {
 448             m_p->present(package, apdu, move_later);
 449         }
 450         else
 451         {
 452             yp2::odr odr;
 453
 454             package.response() = odr.create_close(
 455                 Z_Close_protocolError,
 456                 "unsupported APDU in filter_virt_db");
 457
 458             package.session().close();
 459         }
 460         if (move_later)
 461             package.move();
 462     }
 463     if (package.session().is_closed())
 464         m_p->release_session(package);
 465 }
 466
 467
 468 /*
 469  * Local variables:
 470  * c-basic-offset: 4
 471  * indent-tabs-mode: nil
 472  * c-file-style: "stroustrup"
 473  * End:
 474  * vim: shiftwidth=4 tabstop=8 expandtab
 475  */