1 files changed, 156 insertions, 0 deletions
diff --git a/src/exchangedb/pg_lookup_wire_fee_by_time.c b/src/exchangedb/pg_lookup_wire_fee_by_time.c
new file mode 100644
index 000000000..775232a48
--- /dev/null
+++ b/src/exchangedb/pg_lookup_wire_fee_by_time.c
@@ -0,0 +1,156 @@
+/*
+   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 exchangedb/pg_lookup_wire_fee_by_time.c
+ * @brief Implementation of the lookup_wire_fee_by_time function for Postgres
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include "taler_error_codes.h"
+#include "taler_dbevents.h"
+#include "taler_pq_lib.h"
+#include "pg_lookup_wire_fee_by_time.h"
+#include "pg_helper.h"
+
+
+/**
+ * Closure for #wire_fee_by_time_helper()
+ */
+struct WireFeeLookupContext
+{
+
+  /**
+   * Set to the wire fees. Set to invalid if fees conflict over
+   * the given time period.
+   */
+  struct TALER_WireFeeSet *fees;
+
+  /**
+   * Plugin context.
+   */
+  struct PostgresClosure *pg;
+};
+
+
+/**
+ * Helper function for #TEH_PG_lookup_wire_fee_by_time().
+ * Calls the callback with the wire fee structure.
+ *
+ * @param cls a `struct WireFeeLookupContext`
+ * @param result db results
+ * @param num_results number of results in @a result
+ */
+static void
+wire_fee_by_time_helper (void *cls,
+                         PGresult *result,
+                         unsigned int num_results)
+{
+  struct WireFeeLookupContext *wlc = cls;
+  struct PostgresClosure *pg = wlc->pg;
+
+  for (unsigned int i = 0; i<num_results; i++)
+  {
+    struct TALER_WireFeeSet fs;
+    struct GNUNET_PQ_ResultSpec rs[] = {
+      TALER_PQ_RESULT_SPEC_AMOUNT ("wire_fee",
+                                   &fs.wire),
+      TALER_PQ_RESULT_SPEC_AMOUNT ("closing_fee",
+                                   &fs.closing),
+      GNUNET_PQ_result_spec_end
+    };
+
+    if (GNUNET_OK !=
+        GNUNET_PQ_extract_result (result,
+                                  rs,
+                                  i))
+    {
+      GNUNET_break (0);
+      /* invalidate */
+      memset (wlc->fees,
+              0,
+              sizeof (struct TALER_WireFeeSet));
+      return;
+    }
+    if (0 == i)
+    {
+      *wlc->fees = fs;
+      continue;
+    }
+    if (0 !=
+        TALER_wire_fee_set_cmp (&fs,
+                                wlc->fees))
+    {
+      /* invalidate */
+      memset (wlc->fees,
+              0,
+              sizeof (struct TALER_WireFeeSet));
+      return;
+    }
+  }
+}
+
+
+/**
+ * Lookup information about known wire fees.  Finds all applicable
+ * fees in the given range. If they are identical, returns the
+ * respective @a fees. If any of the fees
+ * differ between @a start_time and @a end_time, the transaction
+ * succeeds BUT returns an invalid amount for both fees.
+ *
+ * @param cls closure
+ * @param wire_method the wire method to lookup fees for
+ * @param start_time starting time of fee
+ * @param end_time end time of fee
+ * @param[out] fees wire fees for that time period; if
+ *             different fees exists within this time
+ *             period, an 'invalid' amount is returned.
+ * @return transaction status code
+ */
+enum GNUNET_DB_QueryStatus
+TEH_PG_lookup_wire_fee_by_time (
+  void *cls,
+  const char *wire_method,
+  struct GNUNET_TIME_Timestamp start_time,
+  struct GNUNET_TIME_Timestamp end_time,
+  struct TALER_WireFeeSet *fees)
+{
+  struct PostgresClosure *pg = cls;
+  struct GNUNET_PQ_QueryParam params[] = {
+    GNUNET_PQ_query_param_string (wire_method),
+    GNUNET_PQ_query_param_timestamp (&start_time),
+    GNUNET_PQ_query_param_timestamp (&end_time),
+    GNUNET_PQ_query_param_end
+  };
+  struct WireFeeLookupContext wlc = {
+    .fees = fees,
+    .pg = pg
+  };
+  /* used in #postgres_lookup_wire_fee_by_time() */
+  PREPARE (pg,
+           "lookup_wire_fee_by_time",
+           "SELECT"
+           " wire_fee"
+           ",closing_fee"
+           " FROM wire_fee"
+           " WHERE wire_method=$1"
+           " AND end_date > $2"
+           " AND start_date < $3;");
+  return GNUNET_PQ_eval_prepared_multi_select (pg->conn,
+                                               "lookup_wire_fee_by_time",
+                                               params,
+                                               &wire_fee_by_time_helper,
+                                               &wlc);
+}