def form_var_string
      terraform_vars = terraform_metadata
      ec2_credentials = @node.network_driver.raw_fog_credentials
     
      cleaned_data = terraform_vars.select{|k,v|
        !v.is_a?(Hash) && !v.is_a?(Array)
      } # we can't yet handle nested terraform metadata on the command line so no arrays or hashes

      all_vars = cleaned_data.merge({
        :access_key => ec2_credentials["aws_access_key_id"],
        :secret_key => ec2_credentials["aws_secret_access_key"]
      })

      all_vars.collect{|key, value| "-var #{key}=\"#{value}\""}.join("\s")
    end
def form_var_string
      terraform_vars = terraform_metadata
      ec2_credentials = @node.network_driver.raw_fog_credentials
     
      cleaned_data = terraform_vars.select{|k,v|
        !v.is_a?(Hash) && !v.is_a?(Array)
      } # we can't yet handle nested terraform metadata on the command line so no arrays or hashes

      all_vars = cleaned_data.merge({
        :access_key => ec2_credentials["aws_access_key_id"],
        :secret_key => ec2_credentials["aws_secret_access_key"]
      })

      all_vars.collect{|key, value| "-var #{key}=\"#{value}\""}.join("\s")
    end
Get the terraform variables for this stack, and merge in with our EC2 access keys