Jira doesn't recognize en_US.utf8 as a supported collation

Bug Summary:

After upgrading Jira in environments using the collation 'en_US.utf8', an error message is displayed and needs to be manually ignored on each node, if in a clustered environment.

Steps to replicate

1. Have a Postgres database with en_US.utf8 collation/cset:

   CREATE DATABASE jiradb WITH ENCODING 'UTF-8' LC_COLLATE 'en_US.utf8' LC_CTYPE 'en_US.utf8'TEMPLATE template;
   

1. Upgrade Jira to a newer version
2. Start the Application

Expected results

The application is started up without any warning.

Actual results

A warning is displayed that the collation is not supported:

Database: Your database is using an unsupported collation
Your postgres72 database is currently using an unsupported collation: en_US.UTF8. You should change this to a supported collation:
C.UTF-8
C
en_US.UTF-8
POSIX.UTF-8
English_United States.1252
POSIX

Notes

This occurs because the health check verifies against all utf-8 collations, and does not include utf8. utf8 is a supported collation, we are incorrectly reporting this as a failure.

Workaround

Follow the steps in Configuring system properties and add in the following JVM flag for each node:

-Djira.startup.warnings.disable=true

Please note that all other warnings will be ignored as well.