Feature: Add HOSTNAME to environment for ENV filter

Description

$HOSTNAME is a bash specific variable, and not exported by default.

This PR will check to see if the BASH $HOSTNAME is available, otherwise set it using the hostname command.

Then, EXPORT this variable for access using the ENV filter.

PR: https://github.com/elasticsearch/logstash/pull/1396

Environment

None

Status

Assignee

Jason Kendall

Reporter

Jason Kendall

Labels

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Affects versions

Priority

Configure