Hello #CL09KU1K7 I have setup a Webhook that will receive notifications from AWS SNS. The notifications will be about new files being created in a S3 Bucket. I want to capture the name of the new files created in the Bucket using the Webhook's template. The body of the notification looks like this (I've removed some fields for simplicity and formatted it for clarity):

{
'Type': 'Notification',
'MessageId': 'd4aa09a0-6d51-5219-bcb2-68b12345bd7b',
'TopicArn': 'arn:aws:sns:us-east-1:1234567890:sns_topic',
'Subject': 'Amazon S3 Notification',
'Message': '{
  "Records":
    [
      {
        "eventVersion":"2.1",
        "eventSource":"aws:s3",
        "eventTime":"2025-08-12T16:25:24.066Z",
        "s3":{"s3SchemaVersion":"1.0","configurationId":"New file",
          "bucket":{"name":"testing.data","arn":"arn:aws:s3:::testing.data"},
          "object":{"key":"data_file.csv","size":34}
        }
      }
    ]
  }',
'Timestamp': '2025-08-12T16:25:24.883Z',
}

I want to capture the object key "_data_file.csv_" but i haven't been able to. What I've tested is: In the Webhook's template, if I extract, for example, the

MessageId

like this:

"messageId": "{{ body.MessageId }}"

There is no issue. This works fine. But if I try to extract something from inside the

Message

of the body using something like this:

"file_name": "{{ body.Message.Records[0].s3.object.key }}"

Nothing happens, file_name ends up being empty. I thought that maybe the whole

Message

was being parsed as a single string so I did this just to test:

"file_name": "{{ body.Message }}"

This made the Webhook fail with this error: "_unexpected character: line 8 column 23 (char 425)_" It seems like I just cannot access

Message

, not even as a string(?) Does anyone understand this issue and know how to extract the value I'm trying to obtain? Thanks for the help!

The

message

field is a string, so trying to do

Records[0].s3.object.key

will fail.