TransactionCanceledException: Transaction cancelled, please refer cancellation reasons for specific reasons [ConditionalCheckFailed, None]

[KristianLake]

Hi, when executing the following code in a lambda function

  let user = await table.transact('write', transaction).catch((error) => {
    let errorMessage = 'Could not create user'

    console.log(error.getMessage())
    console.log(transaction.TransactItems)

    return {
      error: errorMessage
    }
  })

Assuming the transaction fails and has multiple transactions inside, it does error correctly

neTableError: OneTable execute failed "transactWrite" for "_Generic. Transaction cancelled, please refer cancellation reasons for specific reasons [ConditionalCheckFailed, None]
    at Table.execute 
    at processTicksAndRejections (internal/process/task_queues.js:95:5)
    at async Table.transact {
  context: {
    err: TransactionCanceledException: Transaction cancelled, please refer cancellation reasons for specific reasons [ConditionalCheckFailed, None]

You cant seem to get the more specific error message (cancellation reasons) though.

How do you get the specific error message

The pseudo code for this is

let errorMessage = 'foo'
if(error.cancellationreason[0].code === 'conditionalcheckfailed) {
errormessage = 'foo already exists'
} else if if(error.cancellationreason[1].code === 'conditionalcheckfailed) {
errormessage = 'bar already exists'
} 

Without being able to check which bit of the transaction failed you only know something in the transaction failed but not what.

thanks alot! :)

[mobsense]

With the AWS V3 SDK, you should see those details in

err.context.CancellationReasons.

For the AWS V2 SDK, that info does not exist in the AWS V2 Javascript API. Only in V3.

See aws/aws-sdk-go#2318

Thank you for reaching out about this @guregu. While the CancellationReason structure is present in the API model for DynamoDB, the AWS SDK for Java is the only SDK (V2) that currently supports unmarshalling this structure. I've marked this issue as a Feature Request, and will bring it up in our next sprint.

[mobsense]

Transferring to discussions.