Investigate Stellar XDR Decode error

[ebma]

Context

The vault clients seem to encounter the following error periodically.

XDRConversionError(SdkError("DecodeError(\n    [\n        83,\n        116,\n        101,\n        108,\n        108,\n        97,\n        114,\n        77,\n        101,\n        115,\n        115,\n        97,\n        103,\n        101,\n    ],\n)"))

Encoding the bytes in this array translates to 'Stellar Relay Error'.

It also seems like the error itself happens randomly as during testing it both happened while the vault was idling as well as after fulfilling issue and redeem requests.

The first occurrence of this error was logged on Nov 13th 2024, though it might be that it already happened before that day.

Logs

Jan 22 12:47:08.871  INFO vault::issue: listen_for_issue_requests(): started
Jan 22 12:47:08.871  INFO vault::cancellation: handle_cancellation(): started
Jan 22 12:47:08.871  INFO vault::cancellation: handle_cancellation(): started
Jan 22 12:51:26.511 ERROR stellar_relay_lib::connection::connector::message_reader: poll_messages_from_stellar(): Error occurred during processing xdr message: XDRConversionError(SdkError("DecodeError(\n    [\n        83,\n        116,\n        101,\n        108,\n        108,\n        97,\n        114,\n        77,\n        101,\n        115,\n        115,\n        97,\n        103,\n        101,\n    ],\n)"))
Jan 22 12:51:26.512  INFO stellar_relay_lib::connection::connector::message_reader: poll_messages_from_stellar(): stopped.
Jan 22 12:51:26.513 ERROR stellar_relay_lib::connection::connector::connector: stop(): failed to shutdown tcp stream: Socket is not connected (os error 57)
Jan 22 12:51:26.514 ERROR vault::oracle::agent: listen_for_stellar_messages(): received error message from Stellar: Error { code: ErrMisc, msg: LimitedString([83, 116, 101, 108, 108, 97, 114, 32, 82, 101, 108, 97, 121, 32, 69, 114, 114, 111, 114]) }
Jan 22 12:51:26.514  INFO vault::oracle::agent: listen_for_stellar_messages(): shutting down overlay connection
Jan 22 12:51:26.514  INFO stellar_relay_lib::overlay: stop(): closing connection to overlay network
Jan 22 12:51:26.515  INFO vault::system: try_shutdown_wallet(): stop the resubmission scheduler

TODO

Look into the root cause of this error. Possibly define a different handling for this as the vault client currently restarts once this error is caught. Maybe it's okay to ignore this particular error instead.

[ebma]

This is not a high-priority fix as it does not affect the general execution of the vault client but only causes as restart.