title: DMS replication to Kinesis omit certain fields
body: <p>We have a use case where we have enabled a AWS DMS replication task which streams changes to our Aurora Postgres cluster to a Kinesis Data stream. The replication task is working as expected but the data that its sending to Kinesis Data Stream as json contains fields like <code>metadata</code> that we don't care about and would ideally like to omit them. Is there a way to do this without triggering a Lambda on KDS to remove the unwanted fields from the json?</p>
  <p>I was looking at using table mappings config of the DMS task when KDS is the target, documentation here - <a href="https://docs.aws.amazon.com/dms/latest/userguide/CHAP_Target.Kinesis.html" rel="nofollow noreferrer">https://docs.aws.amazon.com/dms/latest/userguide/CHAP_Target.Kinesis.html</a>. The docs don't mention anything of this sort. Maybe I am missing something.</p>
  <p>The current table mapping for my usecase is as follows -</p>
  <pre><code>{
      &quot;rules&quot;: [
          {
              &quot;rule-type&quot;: &quot;selection&quot;,
              &quot;rule-id&quot;: &quot;1&quot;,
              &quot;rule-name&quot;: &quot;1&quot;,
              &quot;rule-action&quot;: &quot;include&quot;,
              &quot;object-locator&quot;: {
                  &quot;schema-name&quot;: &quot;public&quot;,
                  &quot;table-name&quot;: &quot;%&quot;
              }
          },
          {
              &quot;rule-type&quot;: &quot;object-mapping&quot;,
              &quot;rule-id&quot;: &quot;2&quot;,
              &quot;rule-name&quot;: &quot;DefaultMapToKinesis&quot;,
              &quot;rule-action&quot;: &quot;map-record-to-record&quot;,
              &quot;object-locator&quot;: {
                  &quot;schema-name&quot;: &quot;public&quot;,
                  &quot;table-name&quot;: &quot;testing&quot;
              }
          }
      ]
  }
  </code></pre>
  <p>The table testing only has two columns namely <code>id</code> and <code>value</code> of type <code>varchar</code> and <code>decimal</code> respectively.</p>
  <p>The result I am getting in KDS is as follows -</p>
  <pre><code>{
      &quot;data&quot;: {
          &quot;id&quot;:   &quot;5&quot;,
          &quot;value&quot;:    1111.22
      },
      &quot;metadata&quot;: {
          &quot;timestamp&quot;:    &quot;2022-08-23T09:32:34.222745Z&quot;,
          &quot;record-type&quot;:  &quot;data&quot;,
          &quot;operation&quot;:    &quot;insert&quot;,
          &quot;partition-key-type&quot;:   &quot;schema-table&quot;,
          &quot;schema-name&quot;:  &quot;public&quot;,
          &quot;table-name&quot;:   &quot;testing&quot;,
          &quot;transaction-id&quot;:   145524
      }
  }
  </code></pre>
  <p>As seen above we are only interested in the <code>data</code> key of the json.</p>
  <p>Is there any way in DMS config or KDS to filter on the data portion of the json sent by DMS without involving any new infra like Lambda?</p>