How to backup a file before changing it with "REX Configuration management" (rexify)

Question

How do I backup files when making a change with rex cm (rexify.org) - or do I have to do this manually?

I see no option in the File.pm API - description. I hope there is some undocumented feature.

Background: It's mostly about the initial configuration. If I push a file, I want to make sure, that potential individual changes are saved somewhere.

Answer 1

The release notes for rex version 0.44 mention:

Rex::Ext::Backup - a simple backup module. This module creates a backup of a file before rex changes it.

include qw/Rex::Ext::Backup/;

set backup_location => "backup/%h";

task yourtask => sub {
   file "/etc/foo.conf", content => "new content\n";
};

Here are the docs for the module. Google doesn't see them, probably because of the expired SSL certificate. But there is a bit more info there:

You can use the following modifiers for your backup_location.

• %h - the hostname
• %t - the time (epoch seconds)

If this doesn't work I'd reach out the the rexify folks directly.