zoom: properly handle proxy failover for re-used backends
[metaproxy-moved-to-github.git] / src / filter_zoom.cpp
index 452c18f..0c02b58 100644 (file)
@@ -24,6 +24,8 @@ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 #include <metaproxy/package.hpp>
 #include <metaproxy/util.hpp>
 #include <metaproxy/xmlutil.hpp>
+#include <yaz/comstack.h>
+#include <yaz/poll.h>
 #include "torus.hpp"
 
 #include <libxslt/xsltutils.h>
@@ -85,16 +87,17 @@ namespace metaproxy_1 {
             friend class Impl;
             friend class Frontend;
             std::string zurl;
-            WRBUF m_apdu_wrbuf;
+            mp::wrbuf m_apdu_wrbuf;
             ZOOM_connection m_connection;
             ZOOM_resultset m_resultset;
             std::string m_frontend_database;
             SearchablePtr sptr;
             xsltStylesheetPtr xsp;
-            std::string content_session_id;
+            std::string cproxy_host;
             bool enable_cproxy;
             bool enable_explain;
             xmlDoc *explain_doc;
+            std::string m_proxy;
         public:
             Backend();
             ~Backend();
@@ -148,6 +151,7 @@ namespace metaproxy_1 {
                                   const char *element_set_name,
                                   bool &enable_pz2_retrieval,
                                   bool &enable_pz2_transform,
+                                  bool &enable_record_transform,
                                   bool &assume_marc8_charset);
 
             Z_Records *get_records(Package &package,
@@ -185,6 +189,7 @@ namespace metaproxy_1 {
                            const char *path);
         private:
             void configure_local_records(const xmlNode * ptr, bool test_only);
+            bool check_proxy(const char *proxy);
             FrontendPtr get_frontend(mp::Package &package);
             void release_frontend(mp::Package &package);
             SearchablePtr parse_torus_record(const xmlNode *ptr);
@@ -200,13 +205,17 @@ namespace metaproxy_1 {
             std::string file_path;
             std::string content_proxy_server;
             std::string content_tmp_file;
+            std::string content_config_file;
             bool apdu_log;
             CCL_bibset bibset;
             std::string element_transform;
             std::string element_raw;
             std::string proxy;
             xsltStylesheetPtr explain_xsp;
+            xsltStylesheetPtr record_xsp;
             std::map<std::string,SearchablePtr> s_map;
+            std::string zoom_timeout;
+            int proxy_timeout;
         };
     }
 }
@@ -260,7 +269,6 @@ void yf::Zoom::process(mp::Package &package) const
 
 yf::Zoom::Backend::Backend()
 {
-    m_apdu_wrbuf = wrbuf_alloc();
     m_connection = ZOOM_connection_create(0);
     ZOOM_connection_save_apdu_wrbuf(m_connection, m_apdu_wrbuf);
     m_resultset = 0;
@@ -278,7 +286,6 @@ yf::Zoom::Backend::~Backend()
         xmlFreeDoc(explain_doc);
     ZOOM_connection_destroy(m_connection);
     ZOOM_resultset_destroy(m_resultset);
-    wrbuf_destroy(m_apdu_wrbuf);
 }
 
 
@@ -299,6 +306,21 @@ void yf::Zoom::Backend::get_zoom_error(int *error, char **addinfo,
             *error = yaz_diag_srw_to_bib1(error0);
         else if (!strcmp(dset, "Bib-1"))
             *error = error0;
+        else if (!strcmp(dset, "ZOOM"))
+        {
+            *error = YAZ_BIB1_TEMPORARY_SYSTEM_ERROR;                
+            if (error0 == ZOOM_ERROR_INIT)
+                *error = YAZ_BIB1_INIT_AC_AUTHENTICATION_SYSTEM_ERROR;
+            else if (error0 == ZOOM_ERROR_DECODE)
+            {
+                if (zoom_addinfo)
+                {
+                    if (strstr(zoom_addinfo, "Authentication") ||
+                        strstr(zoom_addinfo, "authentication"))
+                        *error = YAZ_BIB1_INIT_AC_AUTHENTICATION_SYSTEM_ERROR;
+                }
+            }
+        }
         else
             *error = YAZ_BIB1_TEMPORARY_SYSTEM_ERROR;
         
@@ -319,7 +341,7 @@ void yf::Zoom::Backend::connect(std::string zurl,
                                 int *error, char **addinfo,
                                 ODR odr)
 {
-    ZOOM_connection_connect(m_connection, zurl.c_str(), 0);
+    ZOOM_connection_connect(m_connection, zurl.length() ? zurl.c_str() : 0, 0);
     get_zoom_error(error, addinfo, odr);
 }
 
@@ -365,7 +387,6 @@ yf::Zoom::Searchable::Searchable(CCL_bibset base)
     piggyback = true;
     use_turbomarc = true;
     sortStrategy = "embed";
-    urlRecipe = "${md-electronic-url}";
     ccl_bibset = ccl_qual_dup(base);
 }
 
@@ -429,11 +450,13 @@ void yf::Zoom::Impl::release_frontend(mp::Package &package)
 }
 
 yf::Zoom::Impl::Impl() :
-    apdu_log(false), element_transform("pz2") , element_raw("raw")
+    apdu_log(false), element_transform("pz2") , element_raw("raw"),
+    zoom_timeout("40"), proxy_timeout(1)
 {
     bibset = ccl_qual_mk();
 
     explain_xsp = 0;
+    record_xsp = 0;
     srand((unsigned int) time(0));
 }
 
@@ -618,8 +641,8 @@ void yf::Zoom::Impl::configure(const xmlNode *ptr, bool test_only,
                                const char *path)
 {
     std::string explain_xslt_fname;
+    std::string record_xslt_fname;
 
-    content_tmp_file = "/tmp/cf.XXXXXX.p";
     if (path && *path)
     {
         file_path = path;
@@ -649,6 +672,8 @@ void yf::Zoom::Impl::configure(const xmlNode *ptr, bool test_only,
                     proxy = mp::xml::get_text(attr->children);
                 else if (!strcmp((const char *) attr->name, "explain_xsl"))
                     explain_xslt_fname = mp::xml::get_text(attr->children);
+                else if (!strcmp((const char *) attr->name, "record_xsl"))
+                    record_xslt_fname = mp::xml::get_text(attr->children);
                 else
                     throw mp::filter::FilterException(
                         "Bad attribute " + std::string((const char *)
@@ -690,9 +715,19 @@ void yf::Zoom::Impl::configure(const xmlNode *ptr, bool test_only,
             for (attr = ptr->properties; attr; attr = attr->next)
             {
                 if (!strcmp((const char *) attr->name, "server"))
+                {
+                    yaz_log(YLOG_WARN,
+                            "contentProxy's server attribute is deprecated");
+                    yaz_log(YLOG_LOG, 
+                            "Specify config_file instead. For example:");
+                    yaz_log(YLOG_LOG, 
+                            " content_file=\"/etc/cf-proxy/cproxy.cfg\"");
                     content_proxy_server = mp::xml::get_text(attr->children);
+                }
                 else if (!strcmp((const char *) attr->name, "tmp_file"))
                     content_tmp_file = mp::xml::get_text(attr->children);
+                else if (!strcmp((const char *) attr->name, "config_file"))
+                    content_config_file = mp::xml::get_text(attr->children);
                 else
                     throw mp::filter::FilterException(
                         "Bad attribute " + std::string((const char *)
@@ -712,6 +747,21 @@ void yf::Zoom::Impl::configure(const xmlNode *ptr, bool test_only,
                                                        attr->name));
             }
         }
+        else if (!strcmp((const char *) ptr->name, "zoom"))
+        {
+            const struct _xmlAttr *attr;
+            for (attr = ptr->properties; attr; attr = attr->next)
+            {
+                if (!strcmp((const char *) attr->name, "timeout"))
+                    zoom_timeout = mp::xml::get_text(attr->children);
+                else if (!strcmp((const char *) attr->name, "proxy_timeout"))
+                    proxy_timeout = mp::xml::get_int(attr->children, 1);
+                else
+                    throw mp::filter::FilterException(
+                        "Bad attribute " + std::string((const char *)
+                                                       attr->name));
+            }
+        }
         else
         {
             throw mp::filter::FilterException
@@ -755,6 +805,41 @@ void yf::Zoom::Impl::configure(const xmlNode *ptr, bool test_only,
             
         }
     }
+
+    if (record_xslt_fname.length())
+    {
+        const char *path = 0;
+        
+        if (xsldir.length())
+            path = xsldir.c_str();
+        else
+            path = file_path.c_str();
+        
+        char fullpath[1024];
+        char *cp = yaz_filepath_resolve(record_xslt_fname.c_str(),
+                                        path, 0, fullpath);
+        if (!cp)
+        {
+            throw mp::filter::FilterException
+                ("Cannot read XSLT " + record_xslt_fname);
+        }
+
+        xmlDoc *xsp_doc = xmlParseFile(cp);
+        if (!xsp_doc)
+        {
+            throw mp::filter::FilterException
+                ("Cannot parse XSLT " + record_xslt_fname);
+        }
+
+        record_xsp = xsltParseStylesheetDoc(xsp_doc);
+        if (!record_xsp)
+        {
+            xmlFreeDoc(xsp_doc);
+            throw mp::filter::FilterException
+                ("Cannot parse XSLT " + record_xslt_fname);
+            
+        }
+    }
 }
 
 bool yf::Zoom::Frontend::create_content_session(mp::Package &package,
@@ -767,16 +852,98 @@ bool yf::Zoom::Frontend::create_content_session(mp::Package &package,
 {
     if (b->sptr->contentConnector.length())
     {
-        char *fname = (char *) xmalloc(m_p->content_tmp_file.length() + 8);
-        strcpy(fname, m_p->content_tmp_file.c_str());
+        std::string proxyhostname;
+        std::string tmp_file;
+        bool legacy_format = false;
+
+        if (m_p->content_proxy_server.length())
+        {
+            proxyhostname = m_p->content_proxy_server;
+            legacy_format = true;
+        }
+            
+        if (m_p->content_tmp_file.length())
+            tmp_file = m_p->content_tmp_file;
+
+        if (m_p->content_config_file.length())
+        {
+            FILE *inf = fopen(m_p->content_config_file.c_str(), "r");
+            if (inf)
+            {
+                char buf[1024];
+                while (fgets(buf, sizeof(buf)-1, inf))
+                {
+                    char *cp;
+                    cp = strchr(buf, '#');
+                    if (cp)
+                        *cp = '\0';
+                    cp = strchr(buf, '\n');
+                    if (cp)
+                        *cp = '\0';
+                    cp = strchr(buf, ':');
+                    if (cp)
+                    {
+                        char *cp1 = cp;
+                        while (cp1 != buf && cp1[-1] == ' ')
+                            cp1--;
+                        *cp1 = '\0';
+                        cp++;
+                        while (*cp == ' ')
+                            cp++;
+                        if (!strcmp(buf, "proxyhostname"))
+                            proxyhostname = cp; 
+                        if (!strcmp(buf, "sessiondir") && *cp)
+                        {
+                            if (cp[strlen(cp)-1] == '/')
+                                cp[strlen(cp)-1] = '\0';
+                            tmp_file = std::string(cp) + std::string("/cf.XXXXXX.p");
+                        }
+                    }
+                }
+                fclose(inf);
+            }
+            else
+            {
+                package.log("zoom", YLOG_WARN|YLOG_ERRNO,
+                            "unable to open content config %s",
+                            m_p->content_config_file.c_str());
+                *error = YAZ_BIB1_TEMPORARY_SYSTEM_ERROR;
+                *addinfo = (char *)  odr_malloc(odr, 60 + tmp_file.length());
+                sprintf(*addinfo, "unable to open content config %s",
+                        m_p->content_config_file.c_str());
+                return false;
+            }
+        }
+
+        if (proxyhostname.length() == 0)
+        {
+            package.log("zoom", YLOG_WARN, "no proxyhostname");
+            return true;
+        }
+        if (tmp_file.length() == 0)
+        {
+            package.log("zoom", YLOG_WARN, "no tmp_file");
+            return true;
+        }
+
+        char *fname = xstrdup(tmp_file.c_str());
         char *xx = strstr(fname, "XXXXXX");
         if (!xx)
         {
-            xx = fname + strlen(fname);
-            strcat(fname, "XXXXXX");
+            package.log("zoom", YLOG_WARN, "bad tmp_file %s", tmp_file.c_str());
+            *error = YAZ_BIB1_TEMPORARY_SYSTEM_ERROR;
+            *addinfo = (char *)  odr_malloc(odr, 60 + tmp_file.length());
+            sprintf(*addinfo, "bad format of content tmp_file: %s",
+                    tmp_file.c_str());
+            xfree(fname);
+            return false;
         }
         char tmp_char = xx[6];
         sprintf(xx, "%06d", ((unsigned) rand()) % 1000000);
+        if (legacy_format)
+            b->cproxy_host = std::string(xx) + "." + proxyhostname;
+        else
+            b->cproxy_host = proxyhostname + "/" + xx;
         xx[6] = tmp_char;
 
         FILE *file = fopen(fname, "w");
@@ -789,8 +956,7 @@ bool yf::Zoom::Frontend::create_content_session(mp::Package &package,
             xfree(fname);
             return false;
         }
-        b->content_session_id.assign(xx, 6);
-        WRBUF w = wrbuf_alloc();
+        mp::wrbuf w;
         wrbuf_puts(w, "#content_proxy\n");
         wrbuf_printf(w, "connector: %s\n", b->sptr->contentConnector.c_str());
         if (authentication.length())
@@ -800,11 +966,10 @@ bool yf::Zoom::Frontend::create_content_session(mp::Package &package,
         if (realm.length())
             wrbuf_printf(w, "realm: %s\n", realm.c_str());
 
-        fwrite(wrbuf_buf(w), 1, wrbuf_len(w), file);
+        fwrite(w.buf(), 1, w.len(), file);
         fclose(file);
         package.log("zoom", YLOG_LOG, "content file: %s", fname);
         xfree(fname);
-        wrbuf_destroy(w);
     }
     return true;
 }
@@ -814,10 +979,16 @@ yf::Zoom::BackendPtr yf::Zoom::Frontend::get_backend_from_databases(
     std::string &database, int *error, char **addinfo, mp::odr &odr,
     int *proxy_step)
 {
+    bool connection_reuse = false;
+    std::string proxy;
+
     std::list<BackendPtr>::const_iterator map_it;
     if (m_backend && !m_backend->enable_explain && 
         m_backend->m_frontend_database == database)
-        return m_backend;
+    {
+        connection_reuse = true;
+        proxy = m_backend->m_proxy;
+    }
 
     std::string input_args;
     std::string torus_db;
@@ -832,7 +1003,6 @@ yf::Zoom::BackendPtr yf::Zoom::Frontend::get_backend_from_databases(
 
     std::string authentication;
     std::string content_authentication;
-    std::string proxy;
     std::string content_proxy;
     std::string realm = m_p->default_realm;
 
@@ -881,15 +1051,31 @@ yf::Zoom::BackendPtr yf::Zoom::Frontend::get_backend_from_databases(
             char **dstr;
             int dnum = 0;
             nmem_strsplit(((ODR) odr)->mem, ",", value, &dstr, &dnum);
-            if (*proxy_step >= dnum)
-                *proxy_step = 0;
+            if (connection_reuse)
+            {
+                // find the step after our current proxy
+                int i;
+                for (i = 0; i < dnum; i++)
+                    if (!strcmp(proxy.c_str(), dstr[i]))
+                        break;
+                if (i >= dnum - 1)
+                    *proxy_step = 0;
+                else
+                    *proxy_step = i + 1;
+            }
             else
             {
-                proxy = dstr[*proxy_step];
-                
-                (*proxy_step)++;
-                if (*proxy_step == dnum)
+                // step is known.. Guess our proxy from it
+                if (*proxy_step >= dnum)
                     *proxy_step = 0;
+                else
+                {
+                    proxy = dstr[*proxy_step];
+                    
+                    (*proxy_step)++;
+                    if (*proxy_step == dnum)
+                        *proxy_step = 0;
+                }
             }
         }
         else if (!strcmp(name, "cproxysession"))
@@ -914,7 +1100,16 @@ yf::Zoom::BackendPtr yf::Zoom::Frontend::get_backend_from_databases(
             *addinfo = msg;
             return notfound;
         }
+    }    
+    if (proxy.length())
+        package.log("zoom", YLOG_LOG, "proxy: %s", proxy.c_str());
+
+    if (connection_reuse)
+    {
+        m_backend->connect("", error, addinfo, odr);
+        return m_backend;
     }
+
     if (param_user)
     {
         authentication = std::string(param_user);
@@ -947,7 +1142,7 @@ yf::Zoom::BackendPtr yf::Zoom::Frontend::get_backend_from_databases(
         if (!doc)
         {
             *error = YAZ_BIB1_DATABASE_DOES_NOT_EXIST;
-            *addinfo = odr_strdup(odr, database.c_str());
+            *addinfo = odr_strdup(odr, torus_db.c_str());
             BackendPtr b;
             return b;
         }
@@ -980,7 +1175,7 @@ yf::Zoom::BackendPtr yf::Zoom::Frontend::get_backend_from_databases(
     if (!sptr)
     {
         *error = YAZ_BIB1_DATABASE_DOES_NOT_EXIST;
-        *addinfo = odr_strdup(odr, database.c_str());
+        *addinfo = odr_strdup(odr, torus_db.c_str());
         BackendPtr b;
         return b;
     }
@@ -1057,6 +1252,7 @@ yf::Zoom::BackendPtr yf::Zoom::Frontend::get_backend_from_databases(
 
     BackendPtr b(new Backend);
 
+    b->m_proxy = proxy;
     b->sptr = sptr;
     b->xsp = xsp;
     b->m_frontend_database = database;
@@ -1065,7 +1261,7 @@ yf::Zoom::BackendPtr yf::Zoom::Frontend::get_backend_from_databases(
     if (sptr->query_encoding.length())
         b->set_option("rpnCharset", sptr->query_encoding);
 
-    b->set_option("timeout", "40");
+    b->set_option("timeout", m_p->zoom_timeout.c_str());
     
     if (m_p->apdu_log) 
         b->set_option("apdulog", "1");
@@ -1136,9 +1332,6 @@ yf::Zoom::BackendPtr yf::Zoom::Frontend::get_backend_from_databases(
         if (proxy.length())
             b->set_option("proxy", proxy);
     }
-    if (proxy.length())
-        package.log("zoom", YLOG_LOG, "proxy: %s", proxy.c_str());
-                
     std::string url;
     if (sptr->sru.length())
     {
@@ -1179,25 +1372,32 @@ void yf::Zoom::Frontend::prepare_elements(BackendPtr b,
                                           const char *element_set_name,
                                           bool &enable_pz2_retrieval,
                                           bool &enable_pz2_transform,
+                                          bool &enable_record_transform,
                                           bool &assume_marc8_charset)
-
 {
     char oid_name_str[OID_STR_MAX];
     const char *syntax_name = 0;
     
     if (preferredRecordSyntax &&
-        !oid_oidcmp(preferredRecordSyntax, yaz_oid_recsyn_xml)
-        && element_set_name)
+        !oid_oidcmp(preferredRecordSyntax, yaz_oid_recsyn_xml))
     {
-        if (!strcmp(element_set_name, m_p->element_transform.c_str()))
+        if (element_set_name &&
+            !strcmp(element_set_name, m_p->element_transform.c_str()))
         {
             enable_pz2_retrieval = true;
             enable_pz2_transform = true;
         }
-        else if (!strcmp(element_set_name, m_p->element_raw.c_str()))
+        else if (element_set_name && 
+                 !strcmp(element_set_name, m_p->element_raw.c_str()))
         {
             enable_pz2_retrieval = true;
         }
+        else if (m_p->record_xsp)
+        {
+            enable_pz2_retrieval = true;
+            enable_pz2_transform = true;
+            enable_record_transform = true;
+        }
     }
     
     if (enable_pz2_retrieval)
@@ -1310,11 +1510,13 @@ Z_Records *yf::Zoom::Frontend::get_records(Package &package,
     bool enable_pz2_retrieval = false; // whether target profile is used
     bool enable_pz2_transform = false; // whether XSLT is used as well
     bool assume_marc8_charset = false;
+    bool enable_record_transform = false;
 
     prepare_elements(b, preferredRecordSyntax,
                      element_set_name,
                      enable_pz2_retrieval,
                      enable_pz2_transform,
+                     enable_record_transform,
                      assume_marc8_charset);
 
     package.log("zoom", YLOG_LOG, "pz2_retrieval: %s . pz2_transform: %s",
@@ -1341,6 +1543,25 @@ Z_Records *yf::Zoom::Frontend::get_records(Package &package,
     }
     if (i > 0)
     {  // only return records if no error and at least one record
+
+        const char *xsl_parms[3];
+        mp::wrbuf cproxy_host;
+        
+        if (b->enable_cproxy && b->cproxy_host.length())
+        {
+            wrbuf_puts(cproxy_host, "\"");
+            wrbuf_puts(cproxy_host, b->cproxy_host.c_str());
+            wrbuf_puts(cproxy_host, "/\"");
+
+            xsl_parms[0] = "cproxyhost";
+            xsl_parms[1] = wrbuf_cstr(cproxy_host);
+            xsl_parms[2] = 0;
+        }
+        else
+        {
+            xsl_parms[0] = 0;
+        }
+
         char *odr_database = odr_strdup(odr,
                                         b->m_frontend_database.c_str());
         Z_NamePlusRecordList *npl = (Z_NamePlusRecordList *)
@@ -1415,15 +1636,46 @@ Z_Records *yf::Zoom::Frontend::get_records(Package &package,
                     }
                     else
                     { 
-                        xmlDoc *rec_res = 
-                            xsltApplyStylesheet(b->xsp, rec_doc, 0);
+                        // first stage XSLT - per target
+                        xsltStylesheetPtr xsp = b->xsp;
+                        xmlDoc *rec_res = xsltApplyStylesheet(xsp, rec_doc,
+                                                              xsl_parms);
+                        // insert generated-url
+                        if (rec_res)
+                        {
+                            std::string res = 
+                                mp::xml::url_recipe_handle(rec_res,
+                                                           b->sptr->urlRecipe);
+                            if (res.length())
+                            {
+                                xmlNode *ptr = xmlDocGetRootElement(rec_res);
+                                while (ptr && ptr->type != XML_ELEMENT_NODE)
+                                    ptr = ptr->next;
+                                xmlNode *c = 
+                                    xmlNewChild(ptr, 0, BAD_CAST "metadata", 0);
+                                xmlNewProp(c, BAD_CAST "type", BAD_CAST
+                                           "generated-url");
+                                xmlNode * t = xmlNewText(BAD_CAST res.c_str());
+                                xmlAddChild(c, t);
+                            }
+                        }
+                        // second stage XSLT - common
+                        if (rec_res && m_p->record_xsp &&
+                            enable_record_transform)
+                        {
+                            xmlDoc *tmp_doc = rec_res;
 
+                            xsp = m_p->record_xsp;
+                            rec_res = xsltApplyStylesheet(xsp, tmp_doc,
+                                                          xsl_parms);
+                            xmlFreeDoc(tmp_doc);
+                        }
+                        // get result out of it
                         if (rec_res)
                         {
                             xsltSaveResultToString(&xmlrec_buf, &rec_len,
-                                                   rec_res, b->xsp);
+                                                   rec_res, xsp);
                             rec_buf = (const char *) xmlrec_buf;
-                            package.log("zoom", YLOG_LOG, "xslt successful");
                             package.log_write(rec_buf, rec_len);
 
                             xmlFreeDoc(rec_res);
@@ -1444,43 +1696,6 @@ Z_Records *yf::Zoom::Frontend::get_records(Package &package,
                     }
                 }
 
-                if (rec_buf && b->enable_cproxy)
-                {
-                    xmlDoc *doc = xmlParseMemory(rec_buf, rec_len);
-                    std::string res = 
-                        mp::xml::url_recipe_handle(doc, b->sptr->urlRecipe);
-                    if (res.length() && b->content_session_id.length())
-                    {
-                        size_t off = res.find_first_of("://");
-                        if (off != std::string::npos)
-                        {
-                            char tmp[1024];
-                            sprintf(tmp, "%s.%s/",
-                                    b->content_session_id.c_str(),
-                                    m_p->content_proxy_server.c_str());
-                            res.insert(off + 3, tmp);
-                        }
-                    }
-                    if (res.length())
-                    {
-                        xmlNode *ptr = xmlDocGetRootElement(doc);
-                        while (ptr && ptr->type != XML_ELEMENT_NODE)
-                            ptr = ptr->next;
-                        xmlNode *c = 
-                            xmlNewChild(ptr, 0, BAD_CAST "metadata", 0);
-                        xmlNewProp(c, BAD_CAST "type", BAD_CAST
-                                   "generated-url");
-                        xmlNode * t = xmlNewText(BAD_CAST res.c_str());
-                        xmlAddChild(c, t);
-
-                        if (xmlrec_buf)
-                            xmlFree(xmlrec_buf);
-
-                        xmlDocDumpMemory(doc, &xmlrec_buf, &rec_len);
-                        rec_buf = (const char *) xmlrec_buf;
-                    }
-                    xmlFreeDoc(doc);
-                }
                 if (!npr)
                 {
                     if (!rec_buf)
@@ -1648,6 +1863,60 @@ yf::Zoom::BackendPtr yf::Zoom::Frontend::explain_search(mp::Package &package,
     }
 }
 
+static bool wait_conn(COMSTACK cs, int secs)
+{
+    struct yaz_poll_fd pfd;
+
+    yaz_poll_add(pfd.input_mask, yaz_poll_except);
+    if (cs->io_pending && CS_WANT_WRITE)
+        yaz_poll_add(pfd.input_mask, yaz_poll_write);
+    else if (cs->io_pending & CS_WANT_READ)
+        yaz_poll_add(pfd.input_mask, yaz_poll_read);
+
+    pfd.fd = cs_fileno(cs);
+    pfd.client_data = 0;
+    
+    int ret = yaz_poll(&pfd, 1, secs, 0);
+    return ret > 0;
+}
+
+bool yf::Zoom::Impl::check_proxy(const char *proxy)
+{
+    COMSTACK conn = 0;
+    const char *uri = "http://localhost/";
+    void *add;
+    mp::odr odr;
+    bool outcome = false;
+    conn = cs_create_host_proxy(uri, 0, &add, proxy);
+
+    if (!conn)
+        return false;
+
+    Z_GDU *gdu = z_get_HTTP_Request_uri(odr, uri, 0, 1);
+    gdu->u.HTTP_Request->method = odr_strdup(odr, "GET");
+    
+    if (z_GDU(odr, &gdu, 0, 0))
+    {
+        int len;
+        char *buf = odr_getbuf(odr, &len, 0);
+        
+        int ret = cs_connect(conn, add);
+        if (ret > 0 || (ret == 0 && wait_conn(conn, 1)))
+        {
+            while (1)
+            {
+                ret = cs_put(conn, buf, len);
+                if (ret != 1)
+                    break;
+                if (!wait_conn(conn, proxy_timeout))
+                    break;
+            }
+        }
+    }
+    cs_close(conn);
+    return outcome;
+}
+
 void yf::Zoom::Frontend::handle_search(mp::Package &package)
 {
     Z_GDU *gdu = package.request().get();
@@ -1664,6 +1933,8 @@ void yf::Zoom::Frontend::handle_search(mp::Package &package)
         return;
     }
     int proxy_step = 0;
+    int same_retries = 0;
+    int proxy_retries = 0;
 
 next_proxy:
 
@@ -1673,11 +1944,31 @@ next_proxy:
 
     BackendPtr b = get_backend_from_databases(package, db, &error,
                                               &addinfo, odr, &proxy_step);
-    if (error && proxy_step)
+    if (error)
     {
-        package.log("zoom", YLOG_WARN,
-                    "create backend failed: trying next proxy");
-        goto next_proxy;
+        if (b && b->m_proxy.length() && !m_p->check_proxy(b->m_proxy.c_str()))
+        {
+            log_diagnostic(package, error, addinfo);
+            package.log("zoom", YLOG_LOG, "proxy %s fails", b->m_proxy.c_str());
+            m_backend.reset();
+            if (proxy_step) // there is a failover
+            {
+                proxy_retries++;
+                package.log("zoom", YLOG_WARN, "search failed: trying next proxy");
+                goto next_proxy;
+            }
+            error = YAZ_BIB1_INIT_AC_AUTHENTICATION_SYSTEM_ERROR;
+            addinfo = odr_strdup(odr, "proxy failure");
+        }
+        else if (same_retries == 0 && proxy_retries == 0)
+        {
+            log_diagnostic(package, error, addinfo);
+            same_retries++;
+            package.log("zoom", YLOG_WARN, "search failed: retry");
+            m_backend.reset();
+            proxy_step = 0;
+            goto next_proxy;
+        }
     }
     if (error)
     {
@@ -1693,28 +1984,28 @@ next_proxy:
 
     bool enable_pz2_retrieval = false;
     bool enable_pz2_transform = false;
+    bool enable_record_transform = false;
     bool assume_marc8_charset = false;
     prepare_elements(b, sr->preferredRecordSyntax, 0 /*element_set_name */,
                      enable_pz2_retrieval,
                      enable_pz2_transform,
+                     enable_record_transform,
                      assume_marc8_charset);
 
     Odr_int hits = 0;
     Z_Query *query = sr->query;
-    WRBUF ccl_wrbuf = 0;
-    WRBUF pqf_wrbuf = 0;
+    mp::wrbuf ccl_wrbuf;
+    mp::wrbuf pqf_wrbuf;
     std::string sortkeys;
 
     if (query->which == Z_Query_type_1 || query->which == Z_Query_type_101)
     {
         // RPN
-        pqf_wrbuf = wrbuf_alloc();
         yaz_rpnquery_to_wrbuf(pqf_wrbuf, query->u.type_1);
     }
     else if (query->which == Z_Query_type_2)
     {
         // CCL
-        ccl_wrbuf = wrbuf_alloc();
         wrbuf_write(ccl_wrbuf, (const char *) query->u.type_2->buf,
                     query->u.type_2->len);
     }
@@ -1767,7 +2058,7 @@ next_proxy:
             return;
         }
 
-        WRBUF sru_sortkeys_wrbuf = wrbuf_alloc();
+        mp::wrbuf sru_sortkeys_wrbuf;
         if (cql_sortby_to_sortkeys(cn, wrbuf_vp_puts, sru_sortkeys_wrbuf))
         {
             error = YAZ_BIB1_ILLEGAL_SORT_RELATION;
@@ -1776,16 +2067,12 @@ next_proxy:
             log_diagnostic(package, error, addinfo);
             apdu_res = odr.create_searchResponse(apdu_req, error, addinfo);
             package.response() = apdu_res;
-            wrbuf_destroy(sru_sortkeys_wrbuf);
             cql_parser_destroy(cp);
             return;
         }
-        WRBUF sort_spec_wrbuf = wrbuf_alloc();
+        mp::wrbuf sort_spec_wrbuf;
         yaz_srw_sortkeys_to_sort_spec(wrbuf_cstr(sru_sortkeys_wrbuf),
                                       sort_spec_wrbuf);
-        wrbuf_destroy(sru_sortkeys_wrbuf);
-
-        ccl_wrbuf = wrbuf_alloc();
         wrbuf_puts(ccl_wrbuf, ccl_buf);
         
         yaz_tok_cfg_t tc = yaz_tok_cfg_create();
@@ -1820,8 +2107,6 @@ next_proxy:
             }
         }
         yaz_tok_parse_destroy(tp);
-        wrbuf_destroy(sort_spec_wrbuf);
-
         cql_parser_destroy(cp);
     }
     else
@@ -1834,19 +2119,18 @@ next_proxy:
         return;
     }
 
-    if (ccl_wrbuf)
+    if (ccl_wrbuf.len())
     {
         // CCL to PQF
-        assert(pqf_wrbuf == 0);
+        assert(pqf_wrbuf.len() == 0);
         int cerror, cpos;
         struct ccl_rpn_node *cn;
         package.log("zoom", YLOG_LOG, "CCL: %s", wrbuf_cstr(ccl_wrbuf));
         cn = ccl_find_str(b->sptr->ccl_bibset, wrbuf_cstr(ccl_wrbuf),
                           &cerror, &cpos);
-        wrbuf_destroy(ccl_wrbuf);
         if (!cn)
         {
-            char *addinfo = odr_strdup(odr, ccl_err_msg(cerror));
+            char *addinfo = odr_strdup_null(odr, ccl_err_msg(cerror));
             error = YAZ_BIB1_MALFORMED_QUERY;
 
             switch (cerror)
@@ -1869,13 +2153,12 @@ next_proxy:
             package.response() = apdu_res;
             return;
         }
-        pqf_wrbuf = wrbuf_alloc();
         ccl_pquery(pqf_wrbuf, cn);
         package.log("zoom", YLOG_LOG, "RPN: %s", wrbuf_cstr(pqf_wrbuf));
         ccl_rpn_delete(cn);
     }
     
-    assert(pqf_wrbuf);
+    assert(pqf_wrbuf.len());
 
     ZOOM_query q = ZOOM_query_create();
     ZOOM_query_sortby2(q, b->sptr->sortStrategy.c_str(), sortkeys.c_str());
@@ -1885,7 +2168,7 @@ next_proxy:
         int status = 0;
         Z_RPNQuery *zquery;
         zquery = p_query_rpn(odr, wrbuf_cstr(pqf_wrbuf));
-        WRBUF wrb = wrbuf_alloc();
+        mp::wrbuf wrb;
             
         if (!strcmp(b->get_option("sru"), "solr"))
         {
@@ -1911,8 +2194,6 @@ next_proxy:
         }
         ZOOM_query_destroy(q);
         
-        wrbuf_destroy(wrb);
-        wrbuf_destroy(pqf_wrbuf);
         if (status)
         {
             error = YAZ_BIB1_MALFORMED_QUERY;
@@ -1929,15 +2210,33 @@ next_proxy:
         package.log("zoom", YLOG_LOG, "search PQF: %s", wrbuf_cstr(pqf_wrbuf));
         b->search(q, &hits, &error, &addinfo, odr);
         ZOOM_query_destroy(q);
-        wrbuf_destroy(pqf_wrbuf);
     }
 
-    if (error && proxy_step)
+    if (error)
     {
-        // reset below prevent reuse in get_backend_from_databases
-        m_backend.reset();
-        package.log("zoom", YLOG_WARN, "search failed: trying next proxy");
-        goto next_proxy;
+        if (b->m_proxy.length() && !m_p->check_proxy(b->m_proxy.c_str()))
+        {
+            log_diagnostic(package, error, addinfo);
+            package.log("zoom", YLOG_LOG, "proxy %s fails", b->m_proxy.c_str());
+            m_backend.reset();
+            if (proxy_step) // there is a failover
+            {
+                proxy_retries++;
+                package.log("zoom", YLOG_WARN, "search failed: trying next proxy");
+                goto next_proxy;
+            }
+            error = YAZ_BIB1_INIT_AC_AUTHENTICATION_SYSTEM_ERROR;
+            addinfo = odr_strdup(odr, "proxy failure");
+        }
+        else if (same_retries == 0 && proxy_retries == 0)
+        { 
+            log_diagnostic(package, error, addinfo);
+            same_retries++;
+            package.log("zoom", YLOG_WARN, "search failed: retry");
+            m_backend.reset();
+            proxy_step = 0;
+            goto next_proxy;
+        }
     }
 
     const char *element_set_name = 0;