MM2 doesn't retry querying electrums on failed RPC requests

[artemii235]

More info in Discord DM.

[sergeyboyko0791]

@artemii235 did the user get in touch?

[artemii235]

@sergeyboyko0791 Could you please DM cipi on Discord in regards to it?

[artemii235]

@sergeyboyko0791 Any updates? 🙂

[sergeyboyko0791]

If I'm not mistaken, the user has refunded his payment.
@cipig could you please confirm this?

[cipig]

user (taker) has spent makerpayment one week later
https://kmdexplorer.io/address/bJ8tZio1PZZEhdw4CJxauEWYtdHqESNsQm is the KMD address from that swap, maker RB8yufv3YTfdzYnwz5paNnnDynGJG6WsqD sent makerpayment, user RT3WtuEPyxPojQHsQPPP7HWviXA23DLr43 spent it one week later
this is the initial sequence on taker side

      {
         "timestamp" : 1636051505007,
         "event" : {
            "type" : "TakerPaymentWaitForSpendFailed",
            "data" : {
               "error" : "swap:319] swap:756] history:679] JsonRpcError { client_info: \"coin: QC\", request: JsonRpcRequest { jsonrpc: \"2.0\", id: \"24798\", method: \"blockchain.contract.event.get_history\", params: [String(\"1462c3dd3f936d595c9af55978003b27c250441f\"), String(\"f2033ede578e17fa6231047265010445bca8cf1c\"), String(\"ddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef\")] }, error: Transport(\"rpc_clients:1258] rpc_clients:1260] [\\\"rpc_clients:2097] rpc_clients:2095] 20s timed out waiting for the future to complete\\\", \\\"rpc_clients:2097] rpc_clients:2095] 20s timed out waiting for the future to complete\\\", \\\"rpc_clients:2097] rpc_clients:2095] 20s timed out waiting for the future to complete\\\"]\") }"
            }
         }
      },
      {
         "event" : {
            "type" : "TakerPaymentWaitRefundStarted",
            "data" : {
               "wait_until" : 1636079813
            }
         },
         "timestamp" : 1636051505008
      },
      {
         "event" : {
            "type" : "TakerPaymentRefundFailed",
            "data" : {
               "error" : "taker_swap:1219] swap:99] Payment state is not PAYMENT_STATE_SENT, got 2"
            }
         },
         "timestamp" : 1636076114083
      },

the TakerPaymentWaitForSpendFailed error was because of timeouts on the electrums, but the tx was sent and later spent by the maker https://qtum.info/tx/e49635badde717d97179672ef6d077f659ab3d5c305ae1368f4de2fd5aa0512f
swap uuid was 7426a8af-bb9b-4ee1-85f7-f04f4e2bd6ac btw, but it does not contain infos on how the taker was able to finally spend the makerpayment

[artemii235]

@cipig @sergeyboyko0791 Can we close this?

[sergeyboyko0791]

I rechecked it, and this issue is not related to QRC20 protocol.

The only problem is that we stop the swap and try to refund payments if an RPC request fails (in this case Electrum timeout).
Probably we need to try multiple times to execute Electrum/HTTP requests during the swap.

[artemii235]

The only problem is that we stop the swap and try to refund payments if an RPC request fails (in this case Electrum timeout).

Yeah, if it's transport error, then we should retry (maybe unlimited times before timeout). This can even be a good test task.