Line data    Source code

       1             : /*
       2             :    This file is part of TALER
       3             :    Copyright (C) 2024 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_categories.c
      18             :  * @brief Implementation of the lookup_categories 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_categories.h"
      26             : #include "pg_helper.h"
      27             : 
      28             : 
      29             : /**
      30             :  * Context used for TMH_PG_lookup_categories().
      31             :  */
      32             : struct LookupCategoryContext
      33             : {
      34             :   /**
      35             :    * Function to call with the results.
      36             :    */
      37             :   TALER_MERCHANTDB_CategoriesCallback 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 otp_device.
      54             :  *
      55             :  * @param[in,out] cls of type `struct LookupCategoryContext *`
      56             :  * @param result the postgres result
      57             :  * @param num_results the number of results in @a result
      58             :  */
      59             : static void
      60           0 : lookup_categories_cb (void *cls,
      61             :                       PGresult *result,
      62             :                       unsigned int num_results)
      63             : {
      64           0 :   struct LookupCategoryContext *tlc = cls;
      65             : 
      66           0 :   for (unsigned int i = 0; i < num_results; i++)
      67             :   {
      68             :     uint64_t category_id;
      69             :     char *category_name;
      70             :     json_t *category_name_i18n;
      71             :     uint64_t product_count;
      72           0 :     struct GNUNET_PQ_ResultSpec rs[] = {
      73           0 :       GNUNET_PQ_result_spec_uint64 ("category_serial",
      74             :                                     &category_id),
      75           0 :       GNUNET_PQ_result_spec_string ("category_name",
      76             :                                     &category_name),
      77           0 :       TALER_PQ_result_spec_json ("category_name_i18n",
      78             :                                  &category_name_i18n),
      79           0 :       GNUNET_PQ_result_spec_uint64 ("product_count",
      80             :                                     &product_count),
      81             :       GNUNET_PQ_result_spec_end
      82             :     };
      83             : 
      84           0 :     if (GNUNET_OK !=
      85           0 :         GNUNET_PQ_extract_result (result,
      86             :                                   rs,
      87             :                                   i))
      88             :     {
      89           0 :       GNUNET_break (0);
      90           0 :       tlc->extract_failed = true;
      91           0 :       return;
      92             :     }
      93           0 :     tlc->cb (tlc->cb_cls,
      94             :              category_id,
      95             :              category_name,
      96             :              category_name_i18n,
      97             :              product_count);
      98           0 :     GNUNET_PQ_cleanup_result (rs);
      99             :   }
     100             : }
     101             : 
     102             : 
     103             : enum GNUNET_DB_QueryStatus
     104           0 : TMH_PG_lookup_categories (void *cls,
     105             :                           const char *instance_id,
     106             :                           TALER_MERCHANTDB_CategoriesCallback cb,
     107             :                           void *cb_cls)
     108             : {
     109             : 
     110           0 :   struct PostgresClosure *pg = cls;
     111           0 :   struct LookupCategoryContext tlc = {
     112             :     .cb = cb,
     113             :     .cb_cls = cb_cls,
     114             :     /* Can be overwritten by the lookup_categories_cb */
     115             :     .extract_failed = false,
     116             :   };
     117           0 :   struct GNUNET_PQ_QueryParam params[] = {
     118           0 :     GNUNET_PQ_query_param_string (instance_id),
     119             :     GNUNET_PQ_query_param_end
     120             :   };
     121             :   enum GNUNET_DB_QueryStatus qs;
     122             : 
     123           0 :   check_connection (pg);
     124           0 :   PREPARE (pg,
     125             :            "lookup_categories",
     126             :            "SELECT"
     127             :            " mc.category_serial"
     128             :            ",mc.category_name"
     129             :            ",mc.category_name_i18n"
     130             :            ",COALESCE(COUNT(mpc.product_serial),0)"
     131             :            "   AS product_count"
     132             :            " FROM merchant_categories mc"
     133             :            " LEFT JOIN merchant_product_categories mpc"
     134             :            "   USING (category_serial)"
     135             :            " JOIN merchant_instances mi"
     136             :            "   USING (merchant_serial)"
     137             :            " WHERE mi.merchant_id=$1"
     138             :            " GROUP BY mc.category_serial"
     139             :            " ORDER BY mc.category_serial;");
     140           0 :   qs = GNUNET_PQ_eval_prepared_multi_select (pg->conn,
     141             :                                              "lookup_categories",
     142             :                                              params,
     143             :                                              &lookup_categories_cb,
     144             :                                              &tlc);
     145             :   /* If there was an error inside lookup_categories_cb, return a hard error. */
     146           0 :   if (tlc.extract_failed)
     147           0 :     return GNUNET_DB_STATUS_HARD_ERROR;
     148           0 :   return qs;
     149             : }