Make get_peadm_config handle nil values better

In the event a group doesn't exist, or a key doesn't return a value.
Don't error, just return nil for those values.

Author: reidmv

tasks/get_peadm_config.rb

@@ -36,8 +36,8 @@ def config
         'replica_postgresql_host' => postgresql[replica_letter],
         'compilers' => compilers,
         'compiler_pool_address' => groups.dig('PE Master', 'config_data', 'pe_repo', 'compile_master_pool_address'),
-        'internal_compiler_a_pool_address' => groups.dig('PE Compiler Group A', 'classes', 'puppet_enterprise::profile::master', 'puppetdb_host')[1],
-        'internal_compiler_b_pool_address' => groups.dig('PE Compiler Group B', 'classes', 'puppet_enterprise::profile::master', 'puppetdb_host')[1],
+        'internal_compiler_a_pool_address' => groups.dig('PE Compiler Group A', 'classes', 'puppet_enterprise::profile::master', 'puppetdb_host', 1),
+        'internal_compiler_b_pool_address' => groups.dig('PE Compiler Group B', 'classes', 'puppet_enterprise::profile::master', 'puppetdb_host', 1),
       },
       'role-letter' => {
         'server' => {
@@ -106,8 +106,13 @@ def initialize(data)
     # Aids in digging into node groups by name, rather than UUID
     def dig(name, *args)
       group = @data.find { |obj| obj['name'] == name }
-      return group if args.empty?
-      group.dig(*args)
+      if group.nil?
+        nil
+      elsif args.empty?
+        group
+      else
+        group.dig(*args)
+      end
     end
 
     # Return the node pinned to the named group