Create partition in disk

lib/linux_admin/disk.rb

@@ -34,30 +34,59 @@ def partitions
         out.each_line do |l|
           if l =~ /^ [0-9].*/
             p = l.split
-            id,size,fs_type = p[0], p[3], p[5]
-            if size =~ /([0-9\.]*)([KMG])B/
-              size = case $2
-                     when 'K' then
-                       $1.to_f.kilobytes
-                     when 'M' then
-                       $1.to_f.megabytes
-                     when 'G' then
-                       $1.to_f.gigabytes
-                     end
+            args = {:disk => self}
+            fields = [:id, :start_sector, :end_sector,
+                      :size, :partition_type, :fs_type]
+
+            fields.each_index do |i|
+              val = p[i]
+              case fields[i]
+              when :start_sector, :end_sector, :size
+                if val =~ /([0-9\.]*)([KMG])B/
+                  val = case $2
+                        when 'K' then
+                          $1.to_f.kilobytes
+                        when 'M' then
+                          $1.to_f.megabytes
+                        when 'G' then
+                          $1.to_f.gigabytes
+                        end
+                end
+
+              when :id
+                val = val.to_i
+
+              end
+
+              args[fields[i]] = val
             end
-            partitions << Partition.new(:disk => self,
-                                        :id => id.to_i,
-                                        :size => size,
-                                        :fs_type => fs_type)
+            partitions << Partition.new(args)
+
           end
         end
 
         partitions
       end
     end
 
-    def create_partition
-      # TODO
+    def create_partition(partition_type, size)
+      id, start =
+        partitions.empty? ? [1, 0] :
+          [(partitions.last.id + 1),
+            partitions.last.end_sector]
+
+      run(cmd(:parted),
+          :params => { nil => [path, 'mkpart', partition_type,
+                               start, start + size]})
+
+      partition = Partition.new(:disk           => self,
+                                :id             => id,
+                                :start_sector   => start,
+                                :end_sector     => start+size,
+                                :size           => size,
+                                :partition_type => partition_type)
+      partitions << partition
+      partition
     end
   end
 end

lib/linux_admin/partition.rb

@@ -8,7 +8,10 @@
 class LinuxAdmin
   class Partition < LinuxAdmin
     attr_accessor :id
+    attr_accessor :partition_type
     attr_accessor :fs_type
+    attr_accessor :start_sector
+    attr_accessor :end_sector
     attr_accessor :size
     attr_accessor :disk
     attr_accessor :mount_point
@@ -18,6 +21,9 @@ def initialize(args={})
       @size    = args[:size]
       @disk    = args[:disk]
       @fs_type = args[:fs_type]
+      @start_sector   = args[:start_sector]
+      @end_sector     = args[:end_sector]
+      @partition_type = args[:partition_type]
     end
 
     def path

spec/disk_spec.rb

@@ -49,15 +49,66 @@
       disk.partitions[0].id.should == 1
       disk.partitions[0].disk.should == disk
       disk.partitions[0].size.should == 80.5.gigabytes
+      disk.partitions[0].start_sector.should == 1259.megabytes
+      disk.partitions[0].end_sector.should == 81.8.gigabytes
+      disk.partitions[0].partition_type.should == 'primary'
       disk.partitions[0].fs_type.should == 'ntfs'
       disk.partitions[1].id.should == 2
       disk.partitions[1].disk.should == disk
       disk.partitions[1].size.should == 80.5.gigabytes
+      disk.partitions[1].start_sector.should == 81.8.gigabytes
+      disk.partitions[1].end_sector.should == 162.gigabytes
+      disk.partitions[1].partition_type.should == 'primary'
       disk.partitions[1].fs_type.should == 'ext4'
       disk.partitions[2].id.should == 3
       disk.partitions[2].disk.should == disk
       disk.partitions[2].size.should == 1074.megabytes
+      disk.partitions[2].start_sector.should == 162.gigabytes
+      disk.partitions[2].end_sector.should == 163.gigabytes
+      disk.partitions[2].partition_type.should == 'logical'
       disk.partitions[2].fs_type.should == 'linux-swap(v1)'
     end
   end
+
+  describe "#create_partition" do
+    before(:each) do
+      # test disk w/ existing partition
+      @disk = LinuxAdmin::Disk.new :path => '/dev/hda'
+      @disk.instance_variable_set(:@partitions,
+                                  [LinuxAdmin::Partition.new(:id => 1,
+                                                 :end_sector => 1024)])
+    end
+
+    it "uses parted" do
+      @disk.should_receive(:run).
+        with(@disk.cmd(:parted),
+             :params => { nil => ['/dev/hda', 'mkpart', 'primary', 1024, 2048] })
+      @disk.create_partition 'primary', 1024
+    end
+
+    it "returns partition" do
+      @disk.should_receive(:run) # stub out call to parted
+      partition = @disk.create_partition 'primary', 1024
+      partition.should be_an_instance_of(LinuxAdmin::Partition)
+    end
+
+    it "increments partition id" do
+      @disk.should_receive(:run) # stub out call to parted
+      partition = @disk.create_partition 'primary', 1024
+      partition.id.should == 2
+    end
+
+    it "sets partition start to first unused sector on disk" do
+      @disk.should_receive(:run) # stub out call to parted
+      partition = @disk.create_partition 'primary', 1024
+      partition.start_sector.should == 1024
+    end
+
+    it "stores new partition locally" do
+      @disk.should_receive(:run) # stub out call to parted
+      lambda {
+        @disk.create_partition 'primary', 1024
+      }.should change{@disk.partitions.size}.by(1)
+    end
+  end
 end