Line data    Source code

       1             : /*
       2             :    This file is part of TALER
       3             :    Copyright (C) 2022 Taler Systems SA
       4             : 
       5             :    TALER is free software; you can redistribute it and/or modify it under the
       6             :    terms of the GNU General Public License as published by the Free Software
       7             :    Foundation; either version 3, or (at your option) any later version.
       8             : 
       9             :    TALER is distributed in the hope that it will be useful, but WITHOUT ANY
      10             :    WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
      11             :    A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
      12             : 
      13             :    You should have received a copy of the GNU General Public License along with
      14             :    TALER; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
      15             :  */
      16             : /**
      17             :  * @file exchangedb/pg_preflight.c
      18             :  * @brief Implementation of the preflight function for Postgres
      19             :  * @author Christian Grothoff
      20             :  */
      21             : #include "taler/platform.h"
      22             : #include "taler/taler_error_codes.h"
      23             : #include "taler/taler_dbevents.h"
      24             : #include "taler/taler_pq_lib.h"
      25             : #include "pg_preflight.h"
      26             : #include "pg_helper.h"
      27             : #include "plugin_exchangedb_postgres.h"
      28             : 
      29             : 
      30             : /**
      31             :  * Connect to the database if the connection does not exist yet
      32             :  * and check that we are ready to operate.
      33             :  *
      34             :  * @param pg the plugin-specific state
      35             :  * @return #GNUNET_OK on success
      36             :  */
      37             : static enum GNUNET_GenericReturnValue
      38       32454 : internal_setup (struct PostgresClosure *pg)
      39             : {
      40       32454 :   if (NULL == pg->conn)
      41             :   {
      42             : #if AUTO_EXPLAIN
      43             :     /* Enable verbose logging to see where queries do not
      44             :        properly use indices */
      45             :     struct GNUNET_PQ_ExecuteStatement es[] = {
      46             :       GNUNET_PQ_make_try_execute ("LOAD 'auto_explain';"),
      47             :       GNUNET_PQ_make_try_execute ("SET auto_explain.log_min_duration=50;"),
      48             :       GNUNET_PQ_make_try_execute ("SET auto_explain.log_timing=TRUE;"),
      49             :       GNUNET_PQ_make_try_execute ("SET auto_explain.log_analyze=TRUE;"),
      50             :       /* https://wiki.postgresql.org/wiki/Serializable suggests to really
      51             :          force the default to 'serializable' if SSI is to be used. */
      52             :       GNUNET_PQ_make_try_execute (
      53             :         "SET SESSION CHARACTERISTICS AS TRANSACTION ISOLATION LEVEL SERIALIZABLE;"),
      54             :       GNUNET_PQ_make_try_execute ("SET enable_sort=OFF;"),
      55             :       GNUNET_PQ_make_try_execute ("SET enable_seqscan=OFF;"),
      56             :       GNUNET_PQ_make_try_execute ("SET search_path TO exchange;"),
      57             :       /* Mergejoin causes issues, see Postgres #18380 */
      58             :       GNUNET_PQ_make_try_execute ("SET enable_mergejoin=OFF;"),
      59             :       GNUNET_PQ_EXECUTE_STATEMENT_END
      60             :     };
      61             : #else
      62         871 :     struct GNUNET_PQ_ExecuteStatement es[] = {
      63         871 :       GNUNET_PQ_make_try_execute (
      64             :         "SET SESSION CHARACTERISTICS AS TRANSACTION ISOLATION LEVEL SERIALIZABLE;"),
      65         871 :       GNUNET_PQ_make_try_execute ("SET enable_sort=OFF;"),
      66         871 :       GNUNET_PQ_make_try_execute ("SET enable_seqscan=OFF;"),
      67             :       /* Mergejoin causes issues, see Postgres #18380 */
      68         871 :       GNUNET_PQ_make_try_execute ("SET enable_mergejoin=OFF;"),
      69         871 :       GNUNET_PQ_make_try_execute ("SET search_path TO exchange;"),
      70             :       GNUNET_PQ_EXECUTE_STATEMENT_END
      71             :     };
      72             : #endif
      73             :     struct GNUNET_PQ_Context *db_conn;
      74             : 
      75         871 :     db_conn = GNUNET_PQ_connect_with_cfg2 (pg->cfg,
      76             :                                            "exchangedb-postgres",
      77             :                                            "exchange-", /* load_path_suffix */
      78             :                                            es,
      79             :                                            NULL /* prepared statements */,
      80             :                                            GNUNET_PQ_FLAG_CHECK_CURRENT);
      81         871 :     if (NULL == db_conn)
      82           0 :       return GNUNET_SYSERR;
      83             : 
      84         871 :     pg->prep_gen++;
      85         871 :     pg->conn = db_conn;
      86             :   }
      87       32454 :   if (NULL == pg->transaction_name)
      88       32450 :     GNUNET_PQ_reconnect_if_down (pg->conn);
      89       32454 :   return GNUNET_OK;
      90             : }
      91             : 
      92             : 
      93             : enum GNUNET_GenericReturnValue
      94       32454 : TEH_PG_preflight (void *cls)
      95             : {
      96       32454 :   struct PostgresClosure *pg = cls;
      97       32454 :   struct GNUNET_PQ_ExecuteStatement es[] = {
      98       32454 :     GNUNET_PQ_make_execute ("ROLLBACK"),
      99             :     GNUNET_PQ_EXECUTE_STATEMENT_END
     100             :   };
     101             : 
     102       32454 :   if (GNUNET_OK !=
     103       32454 :       internal_setup (pg))
     104           0 :     return GNUNET_SYSERR;
     105       32454 :   if (NULL == pg->transaction_name)
     106       32450 :     return GNUNET_OK; /* all good */
     107           4 :   if (GNUNET_OK ==
     108           4 :       GNUNET_PQ_exec_statements (pg->conn,
     109             :                                  es))
     110             :   {
     111           4 :     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
     112             :                 "BUG: Preflight check rolled back transaction `%s'!\n",
     113             :                 pg->transaction_name);
     114             :   }
     115             :   else
     116             :   {
     117           0 :     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
     118             :                 "BUG: Preflight check failed to rollback transaction `%s'!\n",
     119             :                 pg->transaction_name);
     120             :   }
     121           4 :   pg->transaction_name = NULL;
     122           4 :   return GNUNET_NO;
     123             : }