make_coin_known can experience serialization failures, add retry logic

1 files changed, 18 insertions, 6 deletions

diff --git a/src/exchange/taler-exchange-httpd_deposit.c b/src/exchange/taler-exchange-httpd_deposit.c
index ea319f23..66cbe04c 100644
--- a/src/exchange/taler-exchange-httpd_deposit.c
+++ b/src/exchange/taler-exchange-httpd_deposit.c
@@ -442,12 +442,24 @@ TEH_handler_deposit (struct MHD_Connection *connection,
     enum GNUNET_DB_QueryStatus qs;
 
     /* make sure coin is 'known' in database */
-    qs = TEH_make_coin_known (&deposit.coin,
-                              connection,
-                              &dc.known_coin_id,
-                              &mhd_ret);
-    /* no transaction => no serialization failures should be possible */
-    GNUNET_break (GNUNET_DB_STATUS_SOFT_ERROR != qs);
+    for (unsigned int tries = 0; tries<MAX_TRANSACTION_COMMIT_RETRIES; tries++)
+    {
+      qs = TEH_make_coin_known (&deposit.coin,
+                                connection,
+                                &dc.known_coin_id,
+                                &mhd_ret);
+      /* no transaction => no serialization failures should be possible */
+      if (GNUNET_DB_STATUS_SOFT_ERROR != qs)
+        break;
+    }
+    if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
+    {
+      GNUNET_break (0);
+      return TALER_MHD_reply_with_error (connection,
+                                         MHD_HTTP_INTERNAL_SERVER_ERROR,
+                                         TALER_EC_GENERIC_DB_COMMIT_FAILED,
+                                         "make_coin_known");
+    }
     if (qs < 0)
       return mhd_ret;
   }