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 backenddb/pg_lookup_templates.c
      18              :  * @brief Implementation of the lookup_templates function for Postgres
      19              :  * @author Christian Grothoff
      20              :  */
      21              : #include "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_lookup_templates.h"
      26              : #include "pg_helper.h"
      27              : 
      28              : 
      29              : /**
      30              :  * Context used for TMH_PG_lookup_templates().
      31              :  */
      32              : struct LookupTemplateContext
      33              : {
      34              :   /**
      35              :    * Function to call with the results.
      36              :    */
      37              :   TALER_MERCHANTDB_TemplatesCallback cb;
      38              : 
      39              :   /**
      40              :    * Closure for @a cb.
      41              :    */
      42              :   void *cb_cls;
      43              : 
      44              :   /**
      45              :    * Did database result extraction fail?
      46              :    */
      47              :   bool extract_failed;
      48              : };
      49              : 
      50              : 
      51              : /**
      52              :  * Function to be called with the results of a SELECT statement
      53              :  * that has returned @a num_results results about template.
      54              :  *
      55              :  * @param[in,out] cls of type `struct LookupTemplateContext *`
      56              :  * @param result the postgres result
      57              :  * @param num_results the number of results in @a result
      58              :  */
      59              : static void
      60            4 : lookup_templates_cb (void *cls,
      61              :                      PGresult *result,
      62              :                      unsigned int num_results)
      63              : {
      64            4 :   struct LookupTemplateContext *tlc = cls;
      65              : 
      66            6 :   for (unsigned int i = 0; i < num_results; i++)
      67              :   {
      68              :     char *template_id;
      69              :     char *template_description;
      70            2 :     struct GNUNET_PQ_ResultSpec rs[] = {
      71            2 :       GNUNET_PQ_result_spec_string ("template_id",
      72              :                                     &template_id),
      73            2 :       GNUNET_PQ_result_spec_string ("template_description",
      74              :                                     &template_description),
      75              :       GNUNET_PQ_result_spec_end
      76              :     };
      77              : 
      78            2 :     if (GNUNET_OK !=
      79            2 :         GNUNET_PQ_extract_result (result,
      80              :                                   rs,
      81              :                                   i))
      82              :     {
      83            0 :       GNUNET_break (0);
      84            0 :       tlc->extract_failed = true;
      85            0 :       return;
      86              :     }
      87            2 :     tlc->cb (tlc->cb_cls,
      88              :              template_id,
      89              :              template_description);
      90            2 :     GNUNET_PQ_cleanup_result (rs);
      91              :   }
      92              : }
      93              : 
      94              : 
      95              : enum GNUNET_DB_QueryStatus
      96            4 : TMH_PG_lookup_templates (void *cls,
      97              :                          const char *instance_id,
      98              :                          TALER_MERCHANTDB_TemplatesCallback cb,
      99              :                          void *cb_cls)
     100              : {
     101            4 :   struct PostgresClosure *pg = cls;
     102            4 :   struct LookupTemplateContext tlc = {
     103              :     .cb = cb,
     104              :     .cb_cls = cb_cls,
     105              :     /* Can be overwritten by the lookup_template_cb */
     106              :     .extract_failed = false,
     107              :   };
     108            4 :   struct GNUNET_PQ_QueryParam params[] = {
     109            4 :     GNUNET_PQ_query_param_string (instance_id),
     110              :     GNUNET_PQ_query_param_end
     111              :   };
     112              :   enum GNUNET_DB_QueryStatus qs;
     113              : 
     114            4 :   check_connection (pg);
     115            4 :   PREPARE (pg,
     116              :            "lookup_templates",
     117              :            "SELECT"
     118              :            " template_id"
     119              :            ",template_description"
     120              :            " FROM merchant_template"
     121              :            " JOIN merchant_instances"
     122              :            "   USING (merchant_serial)"
     123              :            " WHERE merchant_instances.merchant_id=$1");
     124            4 :   qs = GNUNET_PQ_eval_prepared_multi_select (pg->conn,
     125              :                                              "lookup_templates",
     126              :                                              params,
     127              :                                              &lookup_templates_cb,
     128              :                                              &tlc);
     129              :   /* If there was an error inside lookup_templates_cb, return a hard error. */
     130            4 :   if (tlc.extract_failed)
     131            0 :     return GNUNET_DB_STATUS_HARD_ERROR;
     132            4 :   return qs;
     133              : }