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::TEXT"
     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              : }