Sending errors are swallowed

[saibotsivad]

When using the sendBatch method (or the send which uses sendBatch), if there is a failure to send, only the Id is kept in the thrown FailedMessagesError:

// https://github.com/bbc/sqs-producer/blob/canary/src/producer.ts#L116
const failedMessagesBatch = failedMessages.concat(
  result?.Failed?.map((entry) => entry.Id) || []
);

What this means is that the results from calling the @aws-sdk/client-sqs SDK's send method are lost.

For example, here's the results from sending an invalid message:

{
  $metadata: {
    httpStatusCode: 200,
    requestId: "5c1b0781-11d5-5563-b10a-58b890adbc51",
    extendedRequestId: undefined,
    cfId: undefined,
    attempts: 1,
    totalRetryDelay: 0,
  },
  Failed: [
    {
      Code: "InvalidParameterValue",
      Id: "06170031688124646",
      Message: "The request include parameter that is not valid for this queue type",
      SenderFault: true,
    },
  ],
}

But because the FailedMessagesError.failedMessages is just string[] it only includes the Id and the Message is lost.

Would you be willing to update the FailedMessagesError to include the full object from Failed?

To avoid backwards compatibility issues, you could do something like:

+export type SqsProducerFailure = {
+  Code?: string,
+  Id?: string,
+  Message?: string
+}
export class FailedMessagesError extends Error {
  /** Ids of messages that failed to send. */
  public failedMessages: string[];
+  /** Raw SQS failure objects. */
+  public sqsFailures?: SqsProducerFailure[]
  /**
   * @param failedMessages Ids of messages that failed to send.
   */
- constructor(failedMessages: string[]) {
+ constructor(failedMessages: string[], sqsFailures?: SqsProducerFailure[]) {
    super(`Failed to send messages: ${failedMessages.join(', ')}`);
    this.failedMessages = failedMessages;
+   if (sqsFailures?.length) this.sqsFailures = sqsFailures;
  }
}