[chef] Re: Re: Re: Re: testing for mounted fs, and trying shell_out

[Booker Bense < >]

On Tue, Sep 25, 2012 at 3:18 PM, Booker Bense 
<
 >
 wrote:

>
> Why not just open /proc/mounts and read it?
>
> Shelling out of ruby code to run a grep pipe seems overly complicated
> and fragile.
>

if  node['ecs']
   mnt = Array.new
   File.open '/proc/mounts' do |io|
     mnt = io.grep(/\/ebs.*md[1-9]/ )
   end
   if ( mnt.empty?)
         # Fail
   else
         # Create awesome
   end
end

If you can write your shell_out in a  few lines of Ruby, it is almost
always faster, simpler and more robust. It is very easy to generate a
false positive error return from a shell command. Because what you're
actually testing is the execution of the shell, not the actual result.

"The Ruby Way" is an excellent source of recipes for doing basic shell stuff.

- Booker C. Bense