Inval ses for diagnostic 'temporary system error'
[metaproxy-moved-to-github.git] / src / filter_session_shared.cpp
index 6319c35..cd6a237 100644 (file)
@@ -1,5 +1,5 @@
 /* This file is part of Metaproxy.
-   Copyright (C) 2005-2008 Index Data
+   Copyright (C) 2005-2009 Index Data
 
 Metaproxy is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free
@@ -36,6 +36,7 @@ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 #include <yaz/otherinfo.h>
 #include <yaz/diagbib1.h>
 #include <yazpp/z-query.h>
+#include <yazpp/record-cache.h>
 #include <map>
 #include <iostream>
 #include <time.h>
@@ -46,6 +47,7 @@ namespace yf = metaproxy_1::filter;
 namespace metaproxy_1 {
 
     namespace filter {
+        // key for session.. We'll only share sessions with same InitKey
         class SessionShared::InitKey {
         public:
             bool operator < (const SessionShared::InitKey &k) const;
@@ -53,13 +55,13 @@ namespace metaproxy_1 {
             InitKey(const InitKey &);
             ~InitKey();
         private:
-            InitKey &operator = (const InitKey &k);
             char *m_idAuthentication_buf;
             int m_idAuthentication_size;
             char *m_otherInfo_buf;
             int m_otherInfo_size;
             ODR m_odr;
         };
+        // worker thread .. for expiry of sessions
         class SessionShared::Worker {
         public:
             Worker(SessionShared::Rep *rep);
@@ -67,6 +69,7 @@ namespace metaproxy_1 {
         private:
             SessionShared::Rep *m_p;
         };
+        // backend result set
         class SessionShared::BackendSet {
         public:
             std::string m_result_set_id;
@@ -75,6 +78,7 @@ namespace metaproxy_1 {
             yazpp_1::Yaz_Z_Query m_query;
             time_t m_time_last_use;
             void timestamp();
+            yazpp_1::RecordCache m_record_cache;
             BackendSet(
                 const std::string &result_set_id,
                 const Databases &databases,
@@ -82,8 +86,10 @@ namespace metaproxy_1 {
             bool search(
                 Package &frontend_package,
                 const Z_APDU *apdu_req,
-                const BackendInstancePtr bp);
+                const BackendInstancePtr bp,
+                Z_Records **z_records);
         };
+        // backend connection instance
         class SessionShared::BackendInstance {
             friend class Rep;
             friend class BackendClass;
@@ -98,6 +104,7 @@ namespace metaproxy_1 {
             mp::Package * m_close_package;
             ~BackendInstance();
         };
+        // backends of some class (all with same InitKey)
         class SessionShared::BackendClass : boost::noncopyable {
             friend class Rep;
             friend struct Frontend;
@@ -108,7 +115,7 @@ namespace metaproxy_1 {
             BackendInstancePtr get_backend(const Package &package);
             void use_backend(BackendInstancePtr b);
             void release_backend(BackendInstancePtr b);
-            void expire();
+            void expire_class();
             yazpp_1::GDU m_init_request;
             yazpp_1::GDU m_init_response;
             boost::mutex m_mutex_backend_class;
@@ -123,6 +130,7 @@ namespace metaproxy_1 {
                          int session_ttl);
             ~BackendClass();
         };
+        // frontend result set
         class SessionShared::FrontendSet {
             Databases m_databases;
             yazpp_1::Yaz_Z_Query m_query;
@@ -134,6 +142,7 @@ namespace metaproxy_1 {
                 const yazpp_1::Yaz_Z_Query &query);
             FrontendSet();
         };
+        // frontend session
         struct SessionShared::Frontend {
             Frontend(Rep *rep);
             ~Frontend();
@@ -157,6 +166,7 @@ namespace metaproxy_1 {
             BackendClassPtr m_backend_class;
             FrontendSets m_frontend_sets;
         };            
+        // representation
         class SessionShared::Rep {
             friend class SessionShared;
             friend struct Frontend;
@@ -270,7 +280,15 @@ void yf::SessionShared::BackendClass::remove_backend(BackendInstancePtr b)
     while (it != m_backend_list.end())
     {
         if (*it == b)
+        {
+             mp::odr odr;
+            (*it)->m_close_package->response() = odr.create_close(
+                0, Z_Close_lackOfActivity, 0);
+            (*it)->m_close_package->session().close();
+            (*it)->m_close_package->move();
+            
             it = m_backend_list.erase(it);
+        }
         else
             it++;
     }
@@ -473,10 +491,16 @@ yf::SessionShared::BackendSet::BackendSet(
     timestamp();
 }
 
+static int get_diagnostic(Z_DefaultDiagFormat *r)
+{
+    return *r->condition;
+}
+
 bool yf::SessionShared::BackendSet::search(
     mp::Package &frontend_package,
     const Z_APDU *frontend_apdu,
-    const BackendInstancePtr bp)
+    const BackendInstancePtr bp,
+    Z_Records **z_records)
 {
     Package search_package(bp->m_session, frontend_package.origin());
 
@@ -500,41 +524,14 @@ bool yf::SessionShared::BackendSet::search(
     search_package.request() = apdu_req;
 
     search_package.move();
-    
-    Z_Records *z_records_diag = 0;
+
     Z_GDU *gdu = search_package.response().get();
     if (!search_package.session().is_closed()
         && gdu && gdu->which == Z_GDU_Z3950 
         && gdu->u.z3950->which == Z_APDU_searchResponse)
     {
         Z_SearchResponse *b_resp = gdu->u.z3950->u.searchResponse;
-        if (b_resp->records)
-        {
-            if (b_resp->records->which == Z_Records_NSD 
-                || b_resp->records->which == Z_Records_multipleNSD)
-                z_records_diag = b_resp->records;
-        }
-        if (z_records_diag)
-        {
-            if (frontend_apdu->which == Z_APDU_searchRequest)
-            {
-                Z_APDU *f_apdu = odr.create_searchResponse(frontend_apdu, 
-                                                           0, 0);
-                Z_SearchResponse *f_resp = f_apdu->u.searchResponse;
-                f_resp->records = z_records_diag;
-                frontend_package.response() = f_apdu;
-                return false;
-            }
-            if (frontend_apdu->which == Z_APDU_presentRequest)
-            {
-                Z_APDU *f_apdu = odr.create_presentResponse(frontend_apdu, 
-                                                            0, 0);
-                Z_PresentResponse *f_resp = f_apdu->u.presentResponse;
-                f_resp->records = z_records_diag;
-                frontend_package.response() = f_apdu;
-                return false;
-            }
-        }
+        *z_records = b_resp->records;
         m_result_set_size = *b_resp->resultCount;
         return true;
     }
@@ -606,6 +603,9 @@ void yf::SessionShared::Frontend::get_set(mp::Package &package,
                                           BackendInstancePtr &found_backend,
                                           BackendSetPtr &found_set)
 {
+    bool session_restarted = false;
+
+restart:
     std::string result_set_id;
     BackendClassPtr bc = m_backend_class;
     {
@@ -677,11 +677,76 @@ void yf::SessionShared::Frontend::get_set(mp::Package &package,
     // we must search ...
     BackendSetPtr new_set(new BackendSet(result_set_id,
                                          databases, query));
-    if (!new_set->search(package, apdu_req, found_backend))
+    Z_Records *z_records = 0;
+    if (!new_set->search(package, apdu_req, found_backend, &z_records))
     {
         bc->remove_backend(found_backend);
         return; // search error 
     }
+
+    if (z_records)
+    {
+        int condition = 0;
+        if (z_records->which == Z_Records_NSD)
+        {
+            condition =
+                get_diagnostic(z_records->u.nonSurrogateDiagnostic);
+        }
+        else if (z_records->which == Z_Records_multipleNSD)
+        {
+            if (z_records->u.multipleNonSurDiagnostics->num_diagRecs >= 1
+                && 
+                
+                z_records->u.multipleNonSurDiagnostics->diagRecs[0]->which ==
+                Z_DiagRec_defaultFormat)
+            {
+                condition = get_diagnostic(
+                    z_records->u.multipleNonSurDiagnostics->diagRecs[0]->u.defaultFormat);
+                
+            }
+        }
+        if (!session_restarted &&
+            condition == YAZ_BIB1_TEMPORARY_SYSTEM_ERROR)
+        {
+            bc->remove_backend(found_backend);
+            session_restarted = true;
+            found_backend.reset();
+            goto restart;
+
+        }
+
+        if (condition)
+        {
+            mp::odr odr;
+            if (apdu_req->which == Z_APDU_searchRequest)
+            {
+                Z_APDU *f_apdu = odr.create_searchResponse(apdu_req, 
+                                                           0, 0);
+                Z_SearchResponse *f_resp = f_apdu->u.searchResponse;
+                *f_resp->searchStatus = Z_SearchResponse_none;
+                f_resp->records = z_records;
+                package.response() = f_apdu;
+            }
+            if (apdu_req->which == Z_APDU_presentRequest)
+            {
+                Z_APDU *f_apdu = odr.create_presentResponse(apdu_req, 
+                                                            0, 0);
+                Z_PresentResponse *f_resp = f_apdu->u.presentResponse;
+                f_resp->records = z_records;
+                package.response() = f_apdu;
+            }
+            bc->release_backend(found_backend);
+            return; // search error 
+        }
+    }
+    if (!session_restarted && new_set->m_result_set_size < 0)
+    {
+        bc->remove_backend(found_backend);
+        session_restarted = true;
+        found_backend.reset();
+        goto restart;
+    }
+
     found_set = new_set;
     found_set->timestamp();
     found_backend->m_sets.push_back(found_set);
@@ -771,6 +836,33 @@ void yf::SessionShared::Frontend::present(mp::Package &package,
     if (!found_set)
         return;
 
+    Z_NamePlusRecordList *npr_res = 0;
+    if (found_set->m_record_cache.lookup(odr, &npr_res, 
+                                         *req->resultSetStartPoint,
+                                         *req->numberOfRecordsRequested,
+                                         req->preferredRecordSyntax,
+                                         req->recordComposition))
+    {
+        Z_APDU *f_apdu_res = odr.create_presentResponse(apdu_req, 0, 0);
+        Z_PresentResponse *f_resp = f_apdu_res->u.presentResponse;
+
+        yaz_log(YLOG_LOG, "Found %d+%d records in cache %p",
+                *req->resultSetStartPoint,                      
+                *req->numberOfRecordsRequested,
+                &found_set->m_record_cache);        
+
+        *f_resp->numberOfRecordsReturned = *req->numberOfRecordsRequested;
+        *f_resp->nextResultSetPosition = 
+            *req->resultSetStartPoint + *req->numberOfRecordsRequested;
+        // f_resp->presentStatus assumed OK.
+        f_resp->records = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
+        f_resp->records->which = Z_Records_DBOSD;
+        f_resp->records->u.databaseOrSurDiagnostics = npr_res;
+        package.response() = f_apdu_res;
+        bc->release_backend(found_backend);
+        return;
+    }
+                              
     Z_APDU *p_apdu = zget_APDU(odr, Z_APDU_presentRequest);
     Z_PresentRequest *p_req = p_apdu->u.presentRequest;
     p_req->preferredRecordSyntax = req->preferredRecordSyntax;
@@ -802,6 +894,19 @@ void yf::SessionShared::Frontend::present(mp::Package &package,
         f_resp->records = b_resp->records;
         f_resp->otherInfo = b_resp->otherInfo;
         package.response() = f_apdu_res;
+
+        if (b_resp->records && b_resp->records->which ==  Z_Records_DBOSD)
+        {
+            yaz_log(YLOG_LOG, "Adding %d+%d records to cache %p",
+                    *req->resultSetStartPoint,                      
+                    *f_resp->numberOfRecordsReturned,
+                    &found_set->m_record_cache);        
+            found_set->m_record_cache.add(
+                odr,
+                b_resp->records->u.databaseOrSurDiagnostics,
+                *req->resultSetStartPoint,                      
+                *f_resp->numberOfRecordsReturned);
+        }
         bc->release_backend(found_backend);
     }
     else
@@ -852,7 +957,7 @@ void yf::SessionShared::Worker::operator() (void)
     m_p->expire();
 }
 
-void yf::SessionShared::BackendClass::expire()
+void yf::SessionShared::BackendClass::expire_class()
 {
     time_t now;
     time(&now);
@@ -895,7 +1000,7 @@ void yf::SessionShared::Rep::expire()
         
         BackendClassMap::const_iterator b_it = m_backend_map.begin();
         for (; b_it != m_backend_map.end(); b_it++)
-            b_it->second->expire();
+            b_it->second->expire_class();
     }
 }
 
@@ -1096,8 +1201,9 @@ extern "C" {
 /*
  * Local variables:
  * c-basic-offset: 4
+ * c-file-style: "Stroustrup"
  * indent-tabs-mode: nil
- * c-file-style: "stroustrup"
  * End:
  * vim: shiftwidth=4 tabstop=8 expandtab
  */
+