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             : }