Make it possible to disable linked clones

This commit adds a new configuration parameter to allow setting whether to create linked clones on a global, or per pool basis. Without this change vmpooler would always attempt to create linked clones. The default behavior of creating linked clones is preserved.

lib/vmpooler.rb

@@ -64,6 +64,7 @@ module Vmpooler
     parsed_config[:config]['retry_factor'] = string_to_int(ENV['RETRY_FACTOR']) if ENV['RETRY_FACTOR']
     parsed_config[:config]['create_folders'] = ENV['CREATE_FOLDERS'] if ENV['CREATE_FOLDERS']
     parsed_config[:config]['create_template_delta_disks'] = ENV['CREATE_TEMPLATE_DELTA_DISKS'] if ENV['CREATE_TEMPLATE_DELTA_DISKS']
+    set_linked_clone(parsed_config)
     parsed_config[:config]['experimental_features'] = ENV['EXPERIMENTAL_FEATURES'] if ENV['EXPERIMENTAL_FEATURES']
     parsed_config[:config]['purge_unconfigured_folders'] = ENV['PURGE_UNCONFIGURED_FOLDERS'] if ENV['PURGE_UNCONFIGURED_FOLDERS']
     parsed_config[:config]['usage_stats'] = ENV['USAGE_STATS'] if ENV['USAGE_STATS']
@@ -183,4 +184,14 @@ module Vmpooler
     return unless s =~ /\d/
     return Integer(s)
   end
+
+  def self.true?(obj)
+    obj.to_s.downcase == "true"
+  end
+
+  def self.set_linked_clone(parsed_config)
+    parsed_config[:config]['create_linked_clones'] = parsed_config[:config]['create_linked_clones'] || true
+    parsed_config[:config]['create_linked_clones'] = ENV['CREATE_LINKED_CLONES'] if ENV['CREATE_LINKED_CLONES'] =~ /true|false/
+    parsed_config[:config]['create_linked_clones'] = true?(parsed_config[:config]['create_linked_clones']) if parsed_config[:config]['create_linked_clones']
+  end
 end

lib/vmpooler/providers/vsphere.rb

@@ -312,7 +312,7 @@ module Vmpooler
             # Put the VM in the specified folder and resource pool
             relocate_spec = RbVmomi::VIM.VirtualMachineRelocateSpec(
               datastore: find_datastore(target_datastore, connection, target_datacenter_name),
-              diskMoveType: :moveChildMostDiskBacking
+              diskMoveType: get_disk_backing(pool)
             )
 
             manage_host_selection = @config[:config]['manage_host_selection'] if @config[:config].key?('manage_host_selection')
@@ -1028,6 +1028,17 @@ module Vmpooler
           return false if template[-1] == '/'
           return true
         end
+
+        def get_disk_backing(pool)
+          return :moveChildMostDiskBacking if linked_clone?(pool)
+          return :moveAllDiskBackingsAndConsolidate
+        end
+
+        def linked_clone?(pool)
+          return if pool[:create_linked_clone] == false
+          return true if pool[:create_linked_clone]
+          return true if @config[:config]['create_linked_clones']
+        end
       end
     end
   end