Use singleton

src/lib/storage/singleton.rb

@@ -0,0 +1,78 @@
+#!/usr/bin/env ruby
+#
+# encoding: utf-8
+
+# Copyright (c) [2015] SUSE LLC
+#
+# All Rights Reserved.
+#
+# This program is free software; you can redistribute it and/or modify it
+# under the terms of version 2 of the GNU General Public License as published
+# by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+# more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, contact SUSE LLC.
+#
+# To contact SUSE LLC about this file by physical or electronic mail, you may
+# find current contact information at www.suse.com.
+
+require "yast"
+require "storage"
+
+module Yast
+  module Storage
+    # Singleton class for the libstorage object.
+    #
+    # You can simply use Storage.instance to use it and create a libstorage
+    # instance if there isn't one yet; this will use common default parameters
+    # for creating it.
+    #
+    # If you need special parameters for creating it, you can use
+    # Storage.create_instance with a custom ::Storage::Environment (notice the
+    # difference between the global ::Storage namespace which is libstorage and
+    # this Yast::Storage namespace).
+    #
+    # By default (unless disabled in the ::Storage::Environment), creating the
+    # instance will also start hardware probing. This is why there is an alias
+    # name Storage.start_probing to make this explicit.
+    #
+    class Storage
+      class << self
+        @instance = nil
+
+        # Return the singleton for the libstorage object. This will create one
+        # for the first call, which will also trigger hardware probing.
+        def instance
+          create_instance unless @instance
+          @instance
+        end
+
+        # Create the singleton for the libstorage object.
+        #
+        # Create your own Storage::Environment for custom purposes like mocking
+        # the hardware probing etc.
+        def create_instance(storage_environment = nil)
+          if storage_environment.nil?
+            storage_environment = ::Storage::Environment.new(true)
+            # TO DO: Set up logging
+          end
+          # FIXME: Remove this
+          print "Creating Storage object\n"
+          @instance = ::Storage::Storage.new(storage_environment)
+        end
+
+        alias_method :start_probing, :create_instance
+
+        # Destroy the singleton for the libstorage object.
+        def destroy_instance
+          @instance = nil
+        end
+      end
+    end
+  end
+end

src/lib/storage/storage_proposal.rb

@@ -24,6 +24,7 @@
 require "yast"
 require "storage"
 require_relative "./disk_size"
+require_relative "./singleton"
 require "pp"
 
 # This file can be invoked separately for minimal testing.
@@ -125,17 +126,47 @@ def initialize(mount_point)
       # or by resizing an existing Windows partiton.
       #
       class SpaceMaker
+        attr_reader :volumes
+
+        # Initialize.
+        # @param volumes [list of Storage::Volume] volumes to find space for.
+        # The volumes might be changed by this class.
+        #
+        # @param settings [Storage::Settings] parameters to use
+        #
+        def initialize(volumes, settings)
+          @volumes  = volumes
+          @settings = settings
+          storage = Storage.instance
+          storage = Storage.instance
+          storage = Storage.instance
+        end
+
+        # Try to detect empty (unpartitioned) space.
         def find_space
         end
 
+        # Use force to create space: Try to resize an existing Windows
+        # partition or delete partitions until there is enough free space.
         def make_space
         end
 
+        # Check if there are any Linux partitions on any of the disks.
+        # This may be a normal Linux partition (type 0x83), a Linux swap
+        # partition (type 0x82), an LVM partition, or a RAID partition.
+        def linux_partitions?
+        end
+
+        # Check if there is a MS Windows partition that could possibly be
+        # resized.
+        #
+        # @return [bool] 'true# if there is a Windows partition, 'false' if not.
         def windows_partition?
           # TO DO
           false
         end
 
+        # Resize an existing MS Windows partition to free up disk space.
         def resize_windows_partition
           # TO DO
         end
@@ -195,6 +226,13 @@ def choose_disk
 
       # Create a storage proposal.
       def propose
+        # TO DO: Reset staging
+        Storage.start_probing
+        space_maker = SpaceMaker.new(@volumes, @settings)
+      end
+
+      def proposal_text
+        # TO DO
         "No disks found - no storage proposal possible"
       end
     end
@@ -207,5 +245,6 @@ def propose
   proposal = Yast::Storage::Proposal.new
   proposal.settings.root_filesystem_type = :XFS
   proposal.settings.use_separate_home = false
+  proposal.propose
   pp proposal
 end