handle case where purse expiration refunded the coin's deposited amount

src/exchange/taler-exchange-httpd_responses.c

@@ -411,6 +411,8 @@ TEH_RESPONSE_compile_transaction_history (
                                          : pd->exchange_base_url),
                 GNUNET_JSON_pack_data_auto ("purse_pub",
                                             &pd->purse_pub),
+                GNUNET_JSON_pack_bool ("refunded",
+                                       pd->refunded),
                 GNUNET_JSON_pack_data_auto ("coin_sig",
                                             &pd->coin_sig))))
         {
@@ -420,56 +422,6 @@ TEH_RESPONSE_compile_transaction_history (
         }
         break;
       }
-
-#if FIXME_PURSE_REFUND
-    case TALER_EXCHANGEDB_TT_PURSE_REFUND:
-      {
-        struct TALER_EXCHANGEDB_PurseRefundListEntry *pr
-          = pos->details.purse_refund;
-        struct TALER_ExchangePublicKeyP epub;
-        struct TALER_ExchangeSignatureP esig;
-
-        if (TALER_EC_NONE !=
-            TALER_exchange_online_purse_refund_sign (
-              &TEH_keys_exchange_sign_,
-              &pr->amount,
-              &pr->refund_fee,
-              &pr->purse_share_fee,
-              &pr->purse_pub,
-              coin_pub,
-              &epub,
-              &esig))
-        {
-          GNUNET_break (0);
-          json_decref (history);
-          return NULL;
-        }
-        if (0 !=
-            json_array_append_new (
-              history,
-              GNUNET_JSON_PACK (
-                GNUNET_JSON_pack_string ("type",
-                                         "PURSE-REFUND"),
-                TALER_JSON_pack_amount ("amount",
-                                        &pd->amount),
-                TALER_JSON_pack_amount ("refund_fee",
-                                        &pd->refund_fee),
-                TALER_JSON_pack_amount ("purse_share_fee",
-                                        &pd->purse_share_fee),
-                GNUNET_JSON_pack_data_auto ("purse_pub",
-                                            &pd->purse_pub),
-                GNUNET_JSON_pack_data_auto ("exchange_sig",
-                                            &esig),
-                GNUNET_JSON_pack_data_auto ("exchange_pub",
-                                            &epub))))
-        {
-          GNUNET_break (0);
-          json_decref (history);
-          return NULL;
-        }
-        break;
-      }
-#endif
     }
   }
   return history;

src/exchangedb/plugin_exchangedb_postgres.c

@@ -1269,9 +1269,12 @@ prepare_statements (struct PostgresClosure *pg)
       ",purse_pub"
       ",coin_sig"
       ",purse_deposit_serial_id"
+      ",pr.refunded"
       " FROM purse_deposits pd"
       " LEFT JOIN partners"
       "   USING (partner_serial_id)"
+      " JOIN purse_requests pr"
+      "   USING (purse_pub)"
       " JOIN known_coins kc"
       "   ON (pd.coin_pub = kc.coin_pub)"
       " JOIN denominations denoms"
@@ -8314,6 +8317,8 @@ add_coin_purse_deposit (void *cls,
           NULL),
         GNUNET_PQ_result_spec_auto_from_type ("coin_sig",
                                               &deposit->coin_sig),
+        GNUNET_PQ_result_spec_bool ("refunded",
+                                    &deposit->refunded),
         GNUNET_PQ_result_spec_end
       };
 

src/include/taler_exchangedb_plugin.h

@@ -1679,6 +1679,11 @@ struct TALER_EXCHANGEDB_PurseDepositListEntry
    */
   struct TALER_CoinSpendSignatureP coin_sig;
 
+  /**
+   * Set to true if the coin was refunded.
+   */
+  bool refunded;
+
 };
 
 /**

src/lib/exchange_api_common.c

@@ -1185,6 +1185,7 @@ help_purse_deposit (struct CoinHistoryParseContext *pc,
   struct TALER_PurseContractPublicKeyP purse_pub;
   struct TALER_CoinSpendSignatureP coin_sig;
   const char *exchange_base_url;
+  bool refunded;
   struct GNUNET_JSON_Specification spec[] = {
     GNUNET_JSON_spec_fixed_auto ("purse_pub",
                                  &purse_pub),
@@ -1192,6 +1193,8 @@ help_purse_deposit (struct CoinHistoryParseContext *pc,
                                  &coin_sig),
     GNUNET_JSON_spec_string ("exchange_base_url",
                              &exchange_base_url),
+    GNUNET_JSON_spec_bool ("refunded",
+                           &refunded),
     GNUNET_JSON_spec_end ()
   };
 
@@ -1214,6 +1217,23 @@ help_purse_deposit (struct CoinHistoryParseContext *pc,
     GNUNET_break_op (0);
     return GNUNET_SYSERR;
   }
+  if (refunded)
+  {
+    /* We add the amount to refunds here, the original
+       deposit will be added to the balance later because
+       we still return GNUNET_YES, thus effectively
+       cancelling out this operation with respect to
+       the final balance. */
+    if (0 >
+        TALER_amount_add (&pc->rtotal,
+                          &pc->rtotal,
+                          amount))
+    {
+      /* overflow in refund history? inconceivable! Bad exchange! */
+      GNUNET_break_op (0);
+      return GNUNET_SYSERR;
+    }
+  }
   return GNUNET_YES;
 }