1 /* $Id: filter_virt_db.cpp,v 1.25 2006-01-16 01:10:19 adam Exp $
2 Copyright (c) 2005, Index Data.
10 #include "package.hpp"
12 #include <boost/thread/mutex.hpp>
13 #include <boost/thread/condition.hpp>
14 #include <boost/shared_ptr.hpp>
17 #include "filter_virt_db.hpp"
20 #include <yaz/otherinfo.h>
21 #include <yaz/diagbib1.h>
26 namespace yf = yp2::filter;
32 Set(BackendPtr b, std::string setname);
37 std::string m_setname;
40 Map(std::string vhost, std::string route);
45 struct Virt_db::Backend {
46 yp2::Session m_backend_session;
47 std::string m_backend_database;
48 std::string m_frontend_database;
51 bool m_named_result_sets;
54 struct Virt_db::Frontend {
57 yp2::Session m_session;
60 std::list<BackendPtr> m_backend_list;
61 std::map<std::string,Virt_db::Set> m_sets;
63 void search(Package &package, Z_APDU *apdu);
64 void present(Package &package, Z_APDU *apdu);
65 void scan(Package &package, Z_APDU *apdu);
67 void close(Package &package);
68 typedef std::map<std::string,Virt_db::Set>::iterator Sets_it;
70 BackendPtr lookup_backend_from_database(std::string database);
71 BackendPtr create_backend_from_database(std::string database);
73 BackendPtr init_backend(std::string database, Package &package,
74 int &error_code, std::string &addinfo);
79 friend class Frontend;
81 FrontendPtr get_frontend(Package &package);
82 void release_frontend(Package &package);
84 boost::mutex m_sessions_mutex;
85 std::map<std::string, Virt_db::Map>m_maps;
87 typedef std::map<std::string,Virt_db::Set>::iterator Sets_it;
90 boost::condition m_cond_session_ready;
91 std::map<yp2::Session, FrontendPtr> m_clients;
98 yf::Virt_db::BackendPtr yf::Virt_db::Frontend::lookup_backend_from_database(
101 std::list<BackendPtr>::const_iterator map_it;
102 map_it = m_backend_list.begin();
103 for (; map_it != m_backend_list.end(); map_it++)
104 if ((*map_it)->m_frontend_database == database)
110 yf::Virt_db::BackendPtr yf::Virt_db::Frontend::create_backend_from_database(
111 std::string database)
113 std::map<std::string, Virt_db::Map>::iterator map_it;
114 map_it = m_p->m_maps.find(database);
115 if (map_it == m_p->m_maps.end())
120 BackendPtr b(new Backend);
122 b->m_number_of_sets = 0;
123 b->m_frontend_database = database;
124 b->m_named_result_sets = false;
125 b->m_route = map_it->second.m_route;
126 b->m_vhost = map_it->second.m_vhost;
127 const char *sep = strchr(b->m_vhost.c_str(), '/');
128 std::string backend_database;
130 b->m_backend_database = std::string(sep+1);
132 b->m_backend_database = database;
137 yf::Virt_db::BackendPtr yf::Virt_db::Frontend::init_backend(
138 std::string database, Package &package,
139 int &error_code, std::string &addinfo)
141 BackendPtr b = create_backend_from_database(database);
144 error_code = YAZ_BIB1_DATABASE_UNAVAILABLE;
148 Package init_package(b->m_backend_session, package.origin());
149 init_package.copy_filter(package);
153 Z_APDU *init_apdu = zget_APDU(odr, Z_APDU_initRequest);
155 yaz_oi_set_string_oidval(&init_apdu->u.initRequest->otherInfo, odr,
156 VAL_PROXY, 1, b->m_vhost.c_str());
158 Z_InitRequest *req = init_apdu->u.initRequest;
160 ODR_MASK_SET(req->options, Z_Options_search);
161 ODR_MASK_SET(req->options, Z_Options_present);
162 ODR_MASK_SET(req->options, Z_Options_namedResultSets);
163 ODR_MASK_SET(req->options, Z_Options_scan);
165 ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_1);
166 ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_2);
167 ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_3);
169 init_package.request() = init_apdu;
171 init_package.move(b->m_route); // sending init
173 if (init_package.session().is_closed())
175 error_code = YAZ_BIB1_DATABASE_UNAVAILABLE;
180 Z_GDU *gdu = init_package.response().get();
181 // we hope to get an init response
182 if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
185 if (ODR_MASK_GET(gdu->u.z3950->u.initResponse->options,
186 Z_Options_namedResultSets))
188 b->m_named_result_sets = true;
193 error_code = YAZ_BIB1_DATABASE_UNAVAILABLE;
198 m_backend_list.push_back(b);
202 void yf::Virt_db::Frontend::search(Package &package, Z_APDU *apdu_req)
204 Z_SearchRequest *req = apdu_req->u.searchRequest;
206 std::string resultSetId = req->resultSetName;
209 // only one datatabase for now
210 if (req->num_databaseNames != 1)
211 { // exactly one database must be specified
213 odr.create_searchResponse(
214 apdu_req, YAZ_BIB1_TOO_MANY_DATABASES_SPECIFIED, 0);
215 package.response() = apdu;
219 std::string database = std::string(req->databaseNames[0]);
221 BackendPtr b; // null for now
222 Sets_it sets_it = m_sets.find(req->resultSetName);
223 if (sets_it != m_sets.end())
225 // result set already exist
226 // if replace indicator is off: we return diagnostic if
227 // result set already exist.
228 if (*req->replaceIndicator == 0)
231 odr.create_searchResponse(
233 YAZ_BIB1_RESULT_SET_EXISTS_AND_REPLACE_INDICATOR_OFF,
235 package.response() = apdu;
239 sets_it->second.m_backend->m_number_of_sets--;
241 // pick up any existing backend with a database match
242 std::list<BackendPtr>::const_iterator map_it;
243 map_it = m_backend_list.begin();
244 for (; map_it != m_backend_list.end(); map_it++)
246 BackendPtr tmp = *map_it;
247 if (tmp->m_frontend_database == database)
250 if (map_it != m_backend_list.end())
257 // pick up any existing database with named result sets ..
258 // or one which has no result sets.. yet.
259 std::list<BackendPtr>::const_iterator map_it;
260 map_it = m_backend_list.begin();
261 for (; map_it != m_backend_list.end(); map_it++)
263 BackendPtr tmp = *map_it;
264 if (tmp->m_frontend_database == database &&
265 (tmp->m_named_result_sets ||
266 tmp->m_number_of_sets == 0))
269 if (map_it != m_backend_list.end())
272 if (!b) // no backend yet. Must create a new one
276 b = init_backend(database, package, error_code, addinfo);
279 // did not get a backend (unavailable somehow?)
282 odr.create_searchResponse(
283 apdu_req, error_code, addinfo.c_str());
284 package.response() = apdu;
288 m_sets.erase(req->resultSetName);
289 // sending search to backend
290 Package search_package(b->m_backend_session, package.origin());
292 search_package.copy_filter(package);
294 std::string backend_setname;
295 if (b->m_named_result_sets)
297 backend_setname = std::string(req->resultSetName);
301 backend_setname = "default";
302 req->resultSetName = odr_strdup(odr, backend_setname.c_str());
305 const char *backend_database = b->m_backend_database.c_str();
306 req->databaseNames[0] = odr_strdup(odr, backend_database);
308 *req->replaceIndicator = 1;
310 search_package.request() = yazpp_1::GDU(apdu_req);
312 search_package.move(b->m_route);
314 if (search_package.session().is_closed())
317 odr.create_searchResponse(
319 YAZ_BIB1_DATABASE_UNAVAILABLE, database.c_str());
320 package.response() = apdu;
323 package.response() = search_package.response();
325 b->m_number_of_sets++;
327 m_sets[resultSetId] = Virt_db::Set(b, backend_setname);
330 yf::Virt_db::Frontend::Frontend(Rep *rep)
333 m_is_virtual = false;
336 void yf::Virt_db::Frontend::close(Package &package)
338 std::list<BackendPtr>::const_iterator b_it;
340 for (b_it = m_backend_list.begin(); b_it != m_backend_list.end(); b_it++)
342 (*b_it)->m_backend_session.close();
343 Package close_package((*b_it)->m_backend_session, package.origin());
344 close_package.copy_filter(package);
345 close_package.move((*b_it)->m_route);
347 m_backend_list.clear();
350 yf::Virt_db::Frontend::~Frontend()
354 yf::Virt_db::FrontendPtr yf::Virt_db::Rep::get_frontend(Package &package)
356 boost::mutex::scoped_lock lock(m_mutex);
358 std::map<yp2::Session,yf::Virt_db::FrontendPtr>::iterator it;
362 it = m_clients.find(package.session());
363 if (it == m_clients.end())
366 if (!it->second->m_in_use)
368 it->second->m_in_use = true;
371 m_cond_session_ready.wait(lock);
373 FrontendPtr f(new Frontend(this));
374 m_clients[package.session()] = f;
379 void yf::Virt_db::Rep::release_frontend(Package &package)
381 boost::mutex::scoped_lock lock(m_mutex);
382 std::map<yp2::Session,yf::Virt_db::FrontendPtr>::iterator it;
384 it = m_clients.find(package.session());
385 if (it != m_clients.end())
387 if (package.session().is_closed())
389 it->second->close(package);
394 it->second->m_in_use = false;
396 m_cond_session_ready.notify_all();
400 yf::Virt_db::Set::Set(BackendPtr b, std::string setname)
401 : m_backend(b), m_setname(setname)
406 yf::Virt_db::Set::Set()
411 yf::Virt_db::Set::~Set()
415 yf::Virt_db::Map::Map(std::string vhost, std::string route)
416 : m_vhost(vhost), m_route(route)
420 yf::Virt_db::Map::Map()
424 yf::Virt_db::Virt_db() : m_p(new Virt_db::Rep)
428 yf::Virt_db::~Virt_db() {
431 void yf::Virt_db::Frontend::present(Package &package, Z_APDU *apdu_req)
433 Z_PresentRequest *req = apdu_req->u.presentRequest;
434 std::string resultSetId = req->resultSetId;
437 Sets_it sets_it = m_sets.find(resultSetId);
438 if (sets_it == m_sets.end())
441 odr.create_presentResponse(
443 YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST,
444 resultSetId.c_str());
445 package.response() = apdu;
449 new yp2::Session(sets_it->second.m_backend->m_backend_session);
451 // sending present to backend
452 Package present_package(*id, package.origin());
453 present_package.copy_filter(package);
455 req->resultSetId = odr_strdup(odr, "default");
456 present_package.request() = yazpp_1::GDU(apdu_req);
458 present_package.move();
460 if (present_package.session().is_closed())
463 odr.create_presentResponse(
465 YAZ_BIB1_RESULT_SET_NO_LONGER_EXISTS_UNILATERALLY_DELETED_BY_,
466 resultSetId.c_str());
467 package.response() = apdu;
468 m_sets.erase(resultSetId);
472 package.response() = present_package.response();
477 void yf::Virt_db::Frontend::scan(Package &package, Z_APDU *apdu_req)
479 Z_ScanRequest *req = apdu_req->u.scanRequest;
483 // only one datatabase for now
484 if (req->num_databaseNames != 1)
485 { // exactly one database must be specified
487 odr.create_scanResponse(
489 YAZ_BIB1_TOO_MANY_DATABASES_SPECIFIED, 0);
490 package.response() = apdu;
493 std::string database = std::string(req->databaseNames[0]);
496 // pick up any existing backend with a database match
497 std::list<BackendPtr>::const_iterator map_it;
498 map_it = m_backend_list.begin();
499 for (; map_it != m_backend_list.end(); map_it++)
501 BackendPtr tmp = *map_it;
502 if (tmp->m_frontend_database == database)
505 if (map_it != m_backend_list.end())
507 if (!b) // no backend yet. Must create a new one
511 b = init_backend(database, package, error_code, addinfo);
514 // did not get a backend (unavailable somehow?)
516 odr.create_scanResponse(
517 apdu_req, error_code, addinfo.c_str());
518 package.response() = apdu;
523 // sending scan to backend
524 Package scan_package(b->m_backend_session, package.origin());
526 scan_package.copy_filter(package);
528 const char *backend_database = b->m_backend_database.c_str();
529 req->databaseNames[0] = odr_strdup(odr, backend_database);
531 scan_package.request() = yazpp_1::GDU(apdu_req);
533 scan_package.move(b->m_route);
535 if (scan_package.session().is_closed())
538 odr.create_scanResponse(
539 apdu_req, YAZ_BIB1_DATABASE_UNAVAILABLE, database.c_str());
540 package.response() = apdu;
543 package.response() = scan_package.response();
547 void yf::Virt_db::add_map_db2vhost(std::string db, std::string vhost,
550 m_p->m_maps[db] = Virt_db::Map(vhost, route);
553 void yf::Virt_db::process(Package &package) const
555 FrontendPtr f = m_p->get_frontend(package);
557 Z_GDU *gdu = package.request().get();
559 if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
560 Z_APDU_initRequest && !f->m_is_virtual)
562 Z_InitRequest *req = gdu->u.z3950->u.initRequest;
565 yaz_oi_get_string_oidval(&req->otherInfo, VAL_PROXY, 1, 0);
569 Z_APDU *apdu = odr.create_initResponse(gdu->u.z3950, 0, 0);
570 Z_InitResponse *resp = apdu->u.initResponse;
573 static const int masks[] = {
576 Z_Options_namedResultSets,
580 for (i = 0; masks[i] != -1; i++)
581 if (ODR_MASK_GET(req->options, masks[i]))
582 ODR_MASK_SET(resp->options, masks[i]);
584 static const int versions[] = {
590 for (i = 0; versions[i] != -1; i++)
591 if (ODR_MASK_GET(req->protocolVersion, versions[i]))
592 ODR_MASK_SET(resp->protocolVersion, versions[i]);
596 package.response() = apdu;
597 f->m_is_virtual = true;
602 else if (!f->m_is_virtual)
604 else if (gdu && gdu->which == Z_GDU_Z3950)
606 Z_APDU *apdu = gdu->u.z3950;
607 if (apdu->which == Z_APDU_initRequest)
611 package.response() = odr.create_close(
613 Z_Close_protocolError,
616 package.session().close();
618 else if (apdu->which == Z_APDU_searchRequest)
620 f->search(package, apdu);
622 else if (apdu->which == Z_APDU_presentRequest)
624 f->present(package, apdu);
626 else if (apdu->which == Z_APDU_scanRequest)
628 f->scan(package, apdu);
634 package.response() = odr.create_close(
635 apdu, Z_Close_protocolError,
636 "unsupported APDU in filter_virt_db");
638 package.session().close();
641 m_p->release_frontend(package);
645 void yp2::filter::Virt_db::configure(const xmlNode * ptr)
647 for (ptr = ptr->children; ptr; ptr = ptr->next)
649 if (ptr->type != XML_ELEMENT_NODE)
651 if (!strcmp((const char *) ptr->name, "virtual"))
653 std::string database;
655 xmlNode *v_node = ptr->children;
656 for (; v_node; v_node = v_node->next)
658 if (v_node->type != XML_ELEMENT_NODE)
661 if (yp2::xml::is_element_yp2(v_node, "database"))
662 database = yp2::xml::get_text(v_node);
663 else if (yp2::xml::is_element_yp2(v_node, "target"))
664 target = yp2::xml::get_text(v_node);
666 throw yp2::filter::FilterException
668 + std::string((const char *) v_node->name)
669 + " in virtual section"
672 std::string route = yp2::xml::get_route(ptr);
673 add_map_db2vhost(database, target, route);
674 std::cout << "Add " << database << "->" << target
675 << "," << route << "\n";
679 throw yp2::filter::FilterException
681 + std::string((const char *) ptr->name)
682 + " in virt_db filter");
687 static yp2::filter::Base* filter_creator()
689 return new yp2::filter::Virt_db;
693 struct yp2_filter_struct yp2_filter_virt_db = {
704 * indent-tabs-mode: nil
705 * c-file-style: "stroustrup"
707 * vim: shiftwidth=4 tabstop=8 expandtab