1 files changed, 76 insertions, 0 deletions
diff --git a/src/backenddb/pg_lock_product.c b/src/backenddb/pg_lock_product.c
new file mode 100644
index 00000000..205f0b67
--- /dev/null
+++ b/src/backenddb/pg_lock_product.c
@@ -0,0 +1,76 @@
+/*
+   This file is part of TALER
+   Copyright (C) 2022 Taler Systems SA
+
+   TALER is free software; you can redistribute it and/or modify it under the
+   terms of the GNU General Public License as published by the Free Software
+   Foundation; either version 3, or (at your option) any later version.
+
+   TALER is distributed in the hope that it will be useful, but WITHOUT ANY
+   WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+   A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License along with
+   TALER; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+ */
+/**
+ * @file backenddb/pg_lock_product.c
+ * @brief Implementation of the lock_product function for Postgres
+ * @author Iván Ávalos
+ */
+#include "platform.h"
+#include <taler/taler_error_codes.h>
+#include <taler/taler_dbevents.h>
+#include <taler/taler_pq_lib.h>
+#include "pg_lock_product.h"
+#include "pg_helper.h"
+
+enum GNUNET_DB_QueryStatus
+TMH_PG_lock_product (void *cls,
+                     const char *instance_id,
+                     const char *product_id,
+                     const struct GNUNET_Uuid *uuid,
+                     uint64_t quantity,
+                     struct GNUNET_TIME_Timestamp expiration_time)
+{
+  struct PostgresClosure *pg = cls;
+  struct GNUNET_PQ_QueryParam params[] = {
+    GNUNET_PQ_query_param_string (instance_id),
+    GNUNET_PQ_query_param_string (product_id),
+    GNUNET_PQ_query_param_auto_from_type (uuid),
+    GNUNET_PQ_query_param_uint64 (&quantity),
+    GNUNET_PQ_query_param_timestamp (&expiration_time),
+    GNUNET_PQ_query_param_end
+  };
+
+  check_connection (pg);
+  PREPARE (pg,
+           "lock_product",
+           "WITH ps AS"
+           "  (SELECT product_serial"
+           "   FROM merchant_inventory"
+           "   WHERE product_id=$2"
+           "     AND merchant_serial="
+           "     (SELECT merchant_serial"
+           "        FROM merchant_instances"
+           "        WHERE merchant_id=$1))"
+           "INSERT INTO merchant_inventory_locks"
+           "(product_serial"
+           ",lock_uuid"
+           ",total_locked"
+           ",expiration)"
+           " SELECT product_serial, $3, $4, $5"
+           "   FROM merchant_inventory"
+           "   JOIN ps USING (product_serial)"
+           "   WHERE "
+           "     total_stock - total_sold - total_lost - $4 >= "
+           "     (SELECT COALESCE(SUM(total_locked), 0)"
+           "        FROM merchant_inventory_locks"
+           "        WHERE product_serial=ps.product_serial) + "
+           "     (SELECT COALESCE(SUM(total_locked), 0)"
+           "        FROM merchant_order_locks"
+           "        WHERE product_serial=ps.product_serial)");
+  return GNUNET_PQ_eval_prepared_non_select (pg->conn,
+                                             "lock_product",
+                                             params);
+}