If you're using a configurable logging library like logback for Java, it is fairly easy to have your application support both structured logging directly to Elasticsearch, and logging a more human readable format to disk or stderr for development.

It would be nice if there was a standard format you could just ship to a logging service, but the closest seems to be syslog, which is somewhat janky.

Re-parsing logs after they have been formatted for human consumption feels like an anti-pattern motivated by anemic logging libraries.