Question

I’ve create a custom type in Puppet (simplified for this example). If I use it like this (two items in collections)…

 my_type { "example1":
    ensure => present,
    collections => ["abc", "def"]
  }

…in my provider, resource[:collections] is of type Array. That is good, and right.

But if collections contains only 1 item…

 my_type { "example2":
    ensure => present,
    collections => ["abc"],
  }

…resource[:collections] is a String, which is most disconcerting, and a pain in the ass to deal with.

Is this a Ruby thing, a Puppet thing (I’m new to both) or just some cosmic wrinkle in the coding universe I’ve stumbled upon? And more importantly, is there a workaround? Or am I just plain doing it wrong? I’ve been told that before. Don’t hold back.

Answer 1

While I can’t tell you why this happens, the standard workaround for dealing with things that can be either arrays or single objects is using the splat operator like this:[*foo]. In case foo was an array its elements will be “exploded” into a new one, so you still have an array. If foo was just a plain object, you now have a one element array.