WiP: age-withdraw implementation, part 2/n

Commit phase of the age-withdraw protocol implemented, according to
https://docs.taler.net/core/api-exchange.html#withdraw-with-age-restriction

- added new files, forgot in previous commit

2 files changed, 125 insertions, 0 deletions

diff --git a/src/exchangedb/pg_get_age_withdraw_info.c b/src/exchangedb/pg_get_age_withdraw_info.c
new file mode 100644
index 000000000..7662d4b51
--- /dev/null
+++ b/src/exchangedb/pg_get_age_withdraw_info.c
@@ -0,0 +1,80 @@
+/*
+   This file is part of TALER
+   Copyright (C) 2023 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 exchangedb/pg_get_age_withdraw_info.c
+ * @brief Implementation of the get_age_withdraw_info function for Postgres
+ * @author Özgür Kesim
+ */
+#include "platform.h"
+#include "taler_error_codes.h"
+#include "taler_dbevents.h"
+#include "taler_pq_lib.h"
+#include "pg_get_age_withdraw_info.h"
+#include "pg_helper.h"
+
+
+enum GNUNET_DB_QueryStatus
+TEH_PG_get_age_withdraw_info (
+  void *cls,
+  const struct TALER_ReservePublicKeyP *reserve_pub,
+  const struct TALER_AgeWithdrawCommitmentHashP *ach,
+  struct TALER_EXCHANGEDB_AgeWithdrawCommitment *awc)
+{
+  struct PostgresClosure *pg = cls;
+  struct GNUNET_PQ_QueryParam params[] = {
+    GNUNET_PQ_query_param_auto_from_type (ach),
+    GNUNET_PQ_query_param_end
+  };
+  struct GNUNET_PQ_ResultSpec rs[] = {
+    GNUNET_PQ_result_spec_auto_from_type ("h_commitment",
+                                          &awc->h_commitment),
+    GNUNET_PQ_result_spec_auto_from_type ("reserve_sig",
+                                          &awc->reserve_sig),
+    GNUNET_PQ_result_spec_auto_from_type ("reserve_pub",
+                                          &awc->reserve_pub),
+    GNUNET_PQ_result_spec_uint32 ("max_age_group",
+                                  &awc->max_age_group),
+    TALER_PQ_RESULT_SPEC_AMOUNT ("amount_with_fee",
+                                 &awc->amount_with_fee),
+    GNUNET_PQ_result_spec_uint32 ("noreveal_index",
+                                  &awc->noreveal_index),
+    GNUNET_PQ_result_spec_timestamp ("timtestamp",
+                                     &awc->timestamp),
+    GNUNET_PQ_result_spec_end
+  };
+
+  /* Used in #postgres_get_age_withdraw_info() to
+     locate the response for a /reserve/$RESERVE_PUB/age-withdraw request using
+     the hash of the blinded message.  Used to make sure
+     /reserve/$RESERVE_PUB/age-withdraw requests are idempotent. */
+  PREPARE (pg,
+           "get_age_withdraw_info",
+           "SELECT"
+           " h_commitment"
+           ",reserve_sig"
+           ",reserve_pub"
+           ",max_age_group"
+           ",amount_with_fee_val"
+           ",amount_with_fee_frac"
+           ",noreveal_index"
+           ",timestamp"
+           " FROM withdraw_age_commitments"
+           " WHERE h_commitment=$1;");
+  return GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
+                                                   "get_age_withdraw_info",
+                                                   params,
+                                                   rs);
+}
diff --git a/src/exchangedb/pg_get_age_withdraw_info.h b/src/exchangedb/pg_get_age_withdraw_info.h
new file mode 100644
index 000000000..0844b1a19
--- /dev/null
+++ b/src/exchangedb/pg_get_age_withdraw_info.h
@@ -0,0 +1,45 @@
+/*
+   This file is part of TALER
+   Copyright (C) 2023 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 exchangedb/pg_get_age_withdraw_info.h
+ * @brief implementation of the get_age_withdraw_info function for Postgres
+ * @author Özgür KESIM
+ */
+#ifndef PG_GET_AGE_WITHDRAW_INFO_H
+#define PG_GET_AGE_WITHDRAW_INFO_H
+
+#include "taler_util.h"
+#include "taler_json_lib.h"
+#include "taler_exchangedb_plugin.h"
+
+/**
+   * Locate the response for a age-withdraw request under a hash that uniquely
+   * identifies the age-withdraw operation.  Used to ensure idempotency of the
+   * request.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param reserve_pub public key of the reserve for which the age-withdraw request is made
+   * @param ach hash that uniquely identifies the age-withdraw operation
+   * @param[out] awc corresponding details of the previous age-withdraw request if an entry was found
+   * @return statement execution status
+   */
+enum GNUNET_DB_QueryStatus
+TEH_PG_get_age_withdraw_info (
+  void *cls,
+  const struct TALER_ReservePublicKeyP *reserve_pub,
+  const struct TALER_AgeWithdrawCommitmentHashP *ach,
+  struct TALER_EXCHANGEDB_AgeWithdrawCommitment *awc);
+#endif