merchant

commit 4fa367bbcb35bc369df92787eac3fd6ac03e4d8e
parent 2858649b80ef74dfd1687d59a7ba6d4feeeeb57f
Author: Christian Grothoff <christian@grothoff.org>
Date:   Fri, 26 Dec 2025 14:51:35 +0100

implement select_product_groups

Diffstat:
M
src/backenddb/pg_select_product_groups.c
 | 
128
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

1 file changed, 128 insertions(+), 0 deletions(-)
diff --git a/src/backenddb/pg_select_product_groups.c b/src/backenddb/pg_select_product_groups.c
@@ -26,6 +26,76 @@
 #include "pg_helper.h"
 
 
+/**
+ * Context used for TMH_PG_lookup_product_groups().
+ */
+struct LookupProductGroupsContext
+{
+  /**
+   * Function to call with the results.
+   */
+  TALER_MERCHANTDB_ProductGroupsCallback cb;
+
+  /**
+   * Closure for @a cb.
+   */
+  void *cb_cls;
+
+  /**
+   * Did database result extraction fail?
+   */
+  bool extract_failed;
+};
+
+
+/**
+ * Function to be called with the results of a SELECT statement
+ * that has returned @a num_results results about product groups.
+ *
+ * @param[in,out] cls of type `struct LookupProductGroupsContext *`
+ * @param result the postgres result
+ * @param num_results the number of results in @a result
+ */
+static void
+lookup_product_groups_cb (void *cls,
+                          PGresult *result,
+                          unsigned int num_results)
+{
+  struct LookupProductGroupsContext *plc = cls;
+
+  for (unsigned int i = 0; i < num_results; i++)
+  {
+    uint64_t product_group_serial;
+    char *product_group_name;
+    char *product_group_description;
+    struct GNUNET_PQ_ResultSpec rs[] = {
+      GNUNET_PQ_result_spec_uint64 ("product_group_serial",
+                                    &product_group_serial),
+      GNUNET_PQ_result_spec_string ("product_group_name",
+                                    &product_group_name),
+      GNUNET_PQ_result_spec_string ("product_group_description",
+                                    &product_group_description),
+      GNUNET_PQ_result_spec_end
+    };
+
+    if (GNUNET_OK !=
+        GNUNET_PQ_extract_result (result,
+                                  rs,
+                                  i))
+    {
+      GNUNET_break (0);
+      plc->extract_failed = true;
+      return;
+    }
+    plc->cb (plc->cb_cls,
+             product_group_serial,
+             product_group_name,
+             product_group_description);
+    GNUNET_PQ_cleanup_result (rs);
+  }
+}
+
+
 enum GNUNET_DB_QueryStatus
 TMH_PG_select_product_groups (void *cls,
                               const char *instance_id,
@@ -34,4 +104,62 @@ TMH_PG_select_product_groups (void *cls,
                               TALER_MERCHANTDB_ProductGroupsCallback cb,
                               void *cb_cls)
 {
+  struct PostgresClosure *pg = cls;
+  uint64_t plimit = (uint64_t) ((limit < 0) ? -limit : limit);
+  struct LookupProductGroupsContext plc = {
+    .cb = cb,
+    .cb_cls = cb_cls,
+    /* Can be overwritten by the lookup_product_groups_cb */
+    .extract_failed = false,
+  };
+  struct GNUNET_PQ_QueryParam params[] = {
+    GNUNET_PQ_query_param_string (instance_id),
+    GNUNET_PQ_query_param_uint64 (&offset),
+    GNUNET_PQ_query_param_uint64 (&plimit),
+    GNUNET_PQ_query_param_end
+  };
+  enum GNUNET_DB_QueryStatus qs;
+
+  check_connection (pg);
+  PREPARE (pg,
+           "lookup_product_groups_asc",
+           "SELECT"
+           "  product_group_serial"
+           " ,product_group_name"
+           " ,product_group_description"
+           " FROM merchant_product_groups"
+           " JOIN merchant_instances"
+           "   USING (merchant_serial)"
+           " WHERE merchant_instances.merchant_id=$1"
+           "   AND product_group_serial > $2"
+           " ORDER BY product_group_serial ASC"
+           " LIMIT $3");
+  PREPARE (pg,
+           "lookup_product_groups_desc",
+           "SELECT"
+           "  product_group_serial"
+           " ,product_group_name"
+           " ,product_group_description"
+           " FROM merchant_product_groups"
+           " JOIN merchant_instances"
+           "   USING (merchant_serial)"
+           " WHERE merchant_instances.merchant_id=$1"
+           "   AND product_group_serial < $2"
+           " ORDER BY product_group_serial DESC"
+           " LIMIT $3");
+  qs = GNUNET_PQ_eval_prepared_multi_select (
+    pg->conn,
+    (limit > 0)
+    ? "lookup_product_groups_asc"
+    : "lookup_product_groups_desc",
+    params,
+    &lookup_product_groups_cb,
+    &plc);
+  /* If there was an error inside lookup_product_groups_cb, return a hard error. */
+  if (plc.extract_failed)
+  {
+    GNUNET_break (0);
+    return GNUNET_DB_STATUS_HARD_ERROR;
+  }
+  return qs;
 }