sync

commit 24227de303ceeecd73c447bd1058851081d23352
parent 0301428cc8d1cc3bc0006003a9abbdf9bcdfdb0b
Author: Iván Ávalos <avalos@disroot.org>
Date:   Sun,  9 Aug 2026 17:16:54 +0200

create a fresh payment order when the merchant lost the pending one

Diffstat:
M
src/sync/sync-httpd2_payments.c
 | 
67
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++----------

1 file changed, 57 insertions(+), 10 deletions(-)
diff --git a/src/sync/sync-httpd2_payments.c b/src/sync/sync-httpd2_payments.c
@@ -242,8 +242,11 @@ ongoing_payment_cb (void *cls,
  *
  * @param bpc our payment context
  * @param osr order status
+ * @return true if the caller should resume the request, false if a
+ *         fresh order creation was initiated instead (the request was
+ *         re-suspended and will be resumed once that order exists)
  */
-static void
+static bool
 set_payment_response (
   struct BackupPaymentContext *bpc,
   const struct TALER_MERCHANT_GetPrivateOrderResponse *osr)
@@ -257,7 +260,48 @@ set_payment_response (
     bpc->resp = TALER_MHD2_make_error (
       TALER_EC_SYNC_GENERIC_BACKEND_TIMEOUT,
       NULL);
-    return;
+    return true;
+  case MHD_HTTP_STATUS_NOT_FOUND:
+    /* The merchant no longer knows the order we stored as pending (it
+       expired, or the merchant's data was reset).  The stored order is
+       stale and can never be paid: forget it and create a fresh one, so
+       the account payment can still be set up instead of failing every
+       upload with a 502 until the order expires from our own database. */
+    if (NULL != bpc->existing_order_id)
+    {
+      bool suspend;
+
+      GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+                  "Pending order `%s' no longer exists at the merchant,"
+                  " creating a fresh order\n",
+                  bpc->existing_order_id);
+      GNUNET_free (bpc->existing_order_id);
+      bpc->existing_order_id = NULL;
+      bpc->force_fresh_order = true;
+      bpc->resp = SH_begin_payment (bpc,
+                                    GNUNET_NO,
+                                    &suspend);
+      if (suspend)
+        return false; /* fresh order is being created; do not resume yet */
+      return true;
+    }
+    /* The order the client promised to pay (`paying') is gone; tell
+       them to start over. */
+    bpc->resp = TALER_MHD2_MAKE_JSON_PACK (
+      MHD_HTTP_STATUS_BAD_GATEWAY,
+      GNUNET_JSON_pack_uint64 ("code",
+                               TALER_EC_SYNC_GENERIC_BACKEND_ERROR),
+      GNUNET_JSON_pack_string ("hint",
+                               TALER_ErrorCode_get_hint (
+                                 TALER_EC_SYNC_GENERIC_BACKEND_ERROR)),
+      GNUNET_JSON_pack_uint64 ("backend-ec",
+                               (json_int_t) hr->ec),
+      GNUNET_JSON_pack_uint64 ("backend-http-status",
+                               (json_int_t) hr->http_status),
+      GNUNET_JSON_pack_allow_null (
+        GNUNET_JSON_pack_object_incref ("backend-reply",
+                                        (json_t *) hr->reply)));
+    return true;
   case MHD_HTTP_STATUS_OK:
     break; /* handled below */
   default:
@@ -276,7 +320,7 @@ set_payment_response (
       GNUNET_JSON_pack_allow_null (
         GNUNET_JSON_pack_object_incref ("backend-reply",
                                         (json_t *) hr->reply)));
-    return;
+    return true;
   }
 
   GNUNET_assert (MHD_HTTP_STATUS_OK == hr->http_status);
@@ -294,12 +338,12 @@ set_payment_response (
         bpc->order_id,
         GNUNET_TIME_UNIT_YEARS); /* always annual */
       if (0 <= qs)
-        return; /* continue as planned */
+        return true; /* continue as planned */
       GNUNET_break (0);
       bpc->resp = TALER_MHD2_make_error (TALER_EC_GENERIC_DB_STORE_FAILED,
                                          "increment lifetime");
       GNUNET_assert (NULL != bpc->resp);
-      return; /* continue as planned */
+      return true; /* continue as planned */
     }
   case TALER_MERCHANT_OSC_UNPAID:
   case TALER_MERCHANT_OSC_CLAIMED:
@@ -316,13 +360,14 @@ set_payment_response (
                                      ? NULL
                                      : &bpc->token);
     GNUNET_assert (NULL != bpc->resp);
-    return;
+    return true;
   }
   GNUNET_log (GNUNET_ERROR_TYPE_INFO,
               "Timeout waiting for payment\n");
   bpc->resp = TALER_MHD2_make_error (TALER_EC_SYNC_PAYMENT_GENERIC_TIMEOUT,
                                      "Timeout awaiting promised payment");
   GNUNET_assert (NULL != bpc->resp);
+  return true;
 }
 
 
@@ -341,10 +386,12 @@ check_payment_cb (
   GNUNET_CONTAINER_DLL_remove (bpc_head,
                                bpc_tail,
                                bpc);
-  /* Set the response before resuming, MHD needs it in place */
-  set_payment_response (bpc,
-                        osr);
-  resume_request (bpc);
+  /* Set the response before resuming, MHD needs it in place.  A 404 from
+     the merchant for a stale order re-runs the payment initiation (which
+     re-suspends the request); only resume when a final response is set. */
+  if (set_payment_response (bpc,
+                            osr))
+    resume_request (bpc);
 }