Github user bbende commented on the issue:
https://github.com/apache/nifi/pull/2552
@claudiu-stanciu since the principal property supports expression language,
can you just do this?
`foo/${hostname(true)}@ABC.COM`
The parameter to the hostname function indicates to use a fully qualified
hostname:
https://nifi.apache.org/docs/nifi-docs/html/expression-language-guide.html#hostname---
