How to get a substring in the mapped value on a DMS task

Question

I'm trying to create an AWS DMS task to migrate from MongoDB to DynamoDB. While most of it is done, I'm unable to find any documentation or a sample to extract a partial value of a field.

Setup:

• 1 Source Endpoint Mongo DB
• 1 Target Endpoint DynamoDB

• 1 AWS DMS task with the following rules

                   ...
                  {
                      "target-attribute-name": "createdDt",
                      "attribute-type": "scalar",
                      "attribute-sub-type": "string",
                      "value": "${createdDtm}"
                  } 
                  ...
  

Sample value of createdDtm = ISODate("2019-09-05T17:16:33.280-05:00"). I'd like to extract only the date part above such as 2019-09-05. Any suggestions?

I'm unable to create a view in MongoDB because the server is running at 3.2 version and it is not possible to upgrade at this point in time.

Answer 1

I guess there aren't any options - So I've decided to update it in place prior to the DMS task - However if the task is Full load and ongoing - it needs to be ensured that it is corrected at source Mongo