Sending multiple transactions quickly doesn't work

Technical Discussion
#1

If I send multiple transactions within small period (seconds or minutes) then only some of them or no one at all are included in blocks.

My case:

  • testnet
  • all transactions are transfers
  • minimal fee depending on transfer amount and message is calculated and included
  • all transactions are successfully announced, but only some of them or no one are included in blockchain, others expire later
  • that’s true for even a couple of consequent transactions
  • transactions of v2 are used

What am I doing wrong? Could min fee be too low for such scenario?

That’s rather common case for exchanges, I guess, so it definitely should work.

#2

So you are verifying the announce result and you are getting hashes returned from all announced transactions?
To which node did you announce?

#3

So you are verifying the announce result and you are getting hashes returned from all announced transactions?

Yes, exactly.

To which node did you announce?

I’ve tried my own node and a public one. No difference.

#4

Can you retry using HugeTestAlice2.nem.ninja?

#5

Can you retry using HugeTestAlice2.nem.ninja?

The same result.

But I think I’ve just figured out the reason. I use C# SDK, which creates transactions using local time to calculate timestamp. But testnet time is delayed actually. If I make a delay on 30 seconds between signing and announcing then transactions are applied properly.

Ok, it seems like I need to rewrite my code a bit. But bad thing is that nodes silently accept such a transaction and then never apply it.

Anyway - thanks for trying to help!

#6

That seems unlikely to me. What exactly does the returned json object look like?

#7

I see in the log:

2019-01-10 15:01:38.435 WARNING Transaction from TDR5GJVTJT7TDGKKAUNXWY7JAEBFFQDRLH24DVFW rejected (FAILURE_TIMESTAMP_TOO_FAR_IN_FUTURE)

So you should get an error code in the response from announce.

1 Like
#8

Hmm, you are right, error message actually is there:

{
    "Type":1,
    "Code":1,
    "Status":"10",
    "Message":"FAILURE_TIMESTAMP_TOO_FAR_IN_FUTURE",
    "Hash":"d8bb2409ffc902e739c382ae8b82cb7a4353b9063deb449bb19736a217672685",
    "InnerHash":null
}

Actually I checked only the Code field which equals 1 and means Success according to https://nemproject.github.io/#nemRequestResult. Should I check the Status field value instead of Code? There is nothing about it in the docs.

#9

Type 1 means that it has to be interpreted as validation result.
Thus the message should contain a validation result. The list of validation results can be found here:

#10

So, successful result looks like

{
    "Type":1,
    "Code":1,
    "Status":"1",
    "Message":"SUCCESS",
    "Hash":"28e989f679d42aa75a11b657418b042bf0c5e96a6cc0703924f8560dc85c199c",
    "InnerHash":null
}

As I see documentation is wrong:

  1. https://nemproject.github.io/#sending-the-data-to-NIS
  2. https://nemproject.github.io/#nemAnnounceResult
  3. https://nemproject.github.io/#nemRequestResult
  4. https://nemproject.github.io/#appendix-B:-NIS-errors

Third link says that Code field contains success/error code. But actually it always equals 1 and real result is returned as Message and Status pair.

@BloodyRookie, thanks for helping!

UPDATE

Documentation is correct. Code field contains correct value. The error is in C# SDK, which parses result wrongly - https://github.com/NemProject/nem1-sdk-csharp/blob/8233bd3d2ca90e4ac0396afa546dc2ef1beef8e5/src/nem1-sdk/src/Infrastructure/Imported/Api/TransactionRoutesApi.cs#L158

#11

Sorry about that. Fix pushed to master. Thanks for spotting this.