Custom_function nilClass

#Parse_databases.rb snip
module Puppet::Parser::Functions
  newfunction(:parse_databases, :type => :rvalue, :doc =>
    "This function accepts an input hash, a filter and a matcher value.
    It then parses the hash based on the filter, and any matches are returned in a hash.
    If no results are found, then nil is returned.

    Valid filters are:
     * 'database',
     * 'netapp_primary_controller',
     * 'netapp_snapmirror_controller',
     * 'database_primary_server',
     * 'database_replication_server'"
  ) do |arguments|

Puppet::Parser::Functions.autoloader.loadall
...
          db_servers = function_foreman(['fact_values', "fact = ipaddress and (host = #{value['database_primary_server']} or host = #{value['database_replication_server']})"])
          raise Puppet::ParseError, "Foreman function returned no details." if db_servers.nil?
          function_notice(["DB_servers looks like: #{db_servers}. Nil = #{db_servers.nil?}. Class = #{db_servers.class}."])
          db_servers.each do |name, details|
            # Add ipaddress value to allowed_hosts array
            debug "Name = #{name}"
            debug "IPAddress = #{details['ipaddress']}"
            allowed_hosts << details['ipaddress'] unless details['ipaddress'].nil?
          end

# Puppet error
Error: Could not retrieve catalog from remote server: Error 400 on SERVER: undefined method `each' for nil:NilClass at /etc/puppet/modules/common/act/manifests/server/linux/db/oracle.pp:175 on node act-star-db05.card.co.uk
Warning: Not using cache on failed catalog
Error: Could not retrieve catalog; skipping run