Consider other way of letting registrars know about indirect changes

[artur-intech]

It is not yet confirmed, but as I understand, currently to identify a domain that has been deleted registrars parse <msg> element from the following EPP poll response:

<?xml version="1.0" encoding="UTF-8"?>

<epp xmlns="https://epp.tld.ee/schema/epp-ee-1.0.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="lib/schemas/epp-ee-1.0.xsd">
  <response>
    <result code="1301">
      <msg>Command completed successfully; ack to dequeue</msg>
    </result>
    <msgQ count="1" id="1">
      <qDate>2018-04-20T06:17:17Z</qDate>
      <msg>Domain deleted!: bestnames.example</msg>
    </msgQ>
  </response>
</epp>

Parsing plain text of <msg> element is unreliable and inflexible (any single character matters and can potentially lead to an error. Cannot be changed without informing all parties). Instead, we could return machine-readable response like this:

<?xml version="1.0" encoding="UTF-8"?>
<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
  <response>
    <result code="1301">
      <msg>Command completed successfully; ack to dequeue</msg>
    </result>
    <msgQ id="201" count="1">
      <msg>Registry initiated delete of domain.</msg>
    </msgQ>
    <resData>
      <domain:infData xmlns:domain="urn:ietf:params:xml:ns:domain-1.0">
        <domain:name>bestnames.example</domain:name>
      </domain:infData>
    </resData>
    <extension>
      <changePoll:changeData xmlns:changePoll="urn:ietf:params:xml:ns:changePoll-1.0">
        <changePoll:operation op="purge">delete</changePoll:operation>
        <changePoll:date>2013-10-22T14:25:57.0Z</changePoll:date>
      </changePoll:changeData>
    </extension>
  </response>
</epp>

P.S. Some elements are omitted for brevity