module-concat/README.markdown

What is it?
===========

A Puppet module that can construct files from fragments.

Please see the comments in the various .pp files for details
as well as posts on my blog at http://www.devco.net/

Released under the Apache 2.0 licence

Usage:
------

If you wanted a /etc/motd file that listed all the major modules
on the machine.  And that would be maintained automatically even
if you just remove the include lines for other modules you could
use code like below, a sample /etc/motd would be:

<pre>
Puppet modules on this server:

    -- Apache
    -- MySQL
</pre>

Local sysadmins can also append to the file by just editing /etc/motd.local
their changes will be incorporated into the puppet managed motd.

<pre>
# class to setup basic motd, include on all nodes
class motd {
   concat{"/etc/motd":
      owner => root,
      group => root,
      mode  => 644
   }

   concat::fragment{"motd_header":
      content => "\nPuppet modules on this server:\n\n",
      order   => 1,
   }

   # local users on the machine can append to motd by just creating
   # /etc/motd.local
   concat::fragment{"motd_local":
      ensure  => "/etc/motd.local",
      order   => 15
   }
}

# used by other modules to register themselves in the motd
define motd::register($content="", $order=10) {
   if $content == "" {
      $body = $name
   } else {
      $body = $content
   }

   concat::fragment{"motd_fragment_$name":
      target  => "/etc/motd",
      content => "    -- $body\n"
   }
}

# a sample apache module
class apache {
   include apache::install, apache::config, apache::service

   motd::register{"Apache": }
}
</pre>

Known Issues:
-------------
* In 0.24.8 you will see inintended notifies, if you build a file
  in a run, the next run will also see it as changed.  This is due
  to how 0.24.8 does the purging of unhandled files, this is improved
  in 0.25.x and we cannot work around it in our code.

Contributors:
-------------
**Paul Elliot**   

 * Provided 0.24.8 support, shell warnings and empty file creation support.

**Chad Netzer**

 * Various patches to improve safety of file operations
 * Symlink support

**David Schmitt**

 * Patch to remove hard coded paths relying on OS path
 * Patch to use file{} to copy the resulting file to the final destination.  This means Puppet client will show diffs and that hopefully we can change file ownerships now

Contact:
--------
You can contact me on rip@devco.net or follow my blog at http://www.devco.net I am also on twitter as ripienaar