API add_data_disk lun is optional argument.

README.md

@@ -373,13 +373,14 @@ virtual_machine_service.start_virtual_machine('vm_name', 'cloud_service_name')
 virtual_machine_service.restart_virtual_machine('vm_name', 'cloud_service_name')
 
 #API for add disk to Virtual Machine
-lun = 1  #Valid LUN values are 0 through 15.
 options = {
   :disk_label => 'disk-label',
   :disk_size => 100, #In GB
-  :import => false
+  :import => false,
+  :lun => 10,  #Valid LUN values are 0 through 15.
+  :disk_name => 'Disk name' #Required when import is true
 }
-virtual_machine_service.add_data_disk('vm_name', 'cloud_service_name', lun, options)
+virtual_machine_service.add_data_disk('vm_name', 'cloud_service_name', options)
 
 #API to add/update Virtual Machine endpoints
 endpoint1 = {

lib/azure/virtual_machine_management/serialization.rb

@@ -263,6 +263,7 @@ module Azure
               if xml_content(role, 'RoleName') == role_name
                 vm.availability_set_name = xml_content(role, 'AvailabilitySetName')
                 endpoints_from_xml(role, vm)
+                vm.data_disks = data_disks_from_xml(role)
                 vm.os_type = xml_content(role, 'OSVirtualHardDisk OS')
                 vm.disk_name = xml_content(role, 'OSVirtualHardDisk DiskName')
                 vm.media_link = xml_content(role, 'OSVirtualHardDisk MediaLink')
@@ -276,6 +277,20 @@ module Azure
         end
       end
 
+      def self.data_disks_from_xml(rolesXML)
+        data_disks = []
+        virtual_hard_disks = rolesXML.css('DataVirtualHardDisks DataVirtualHardDisk')
+        virtual_hard_disks.each do |disk|
+          data_disk = {}
+          data_disk[:name] = xml_content(disk, 'DiskName')
+          data_disk[:lun] =  xml_content(disk, 'Lun')
+          data_disk[:size_in_gb] = xml_content(disk, 'LogicalDiskSizeInGB')
+          data_disk[:media_link] = xml_content(disk, 'MediaLink')
+          data_disks << data_disk
+        end
+        data_disks
+      end
+
       def self.endpoints_from_xml(rolesXML, vm)
         vm.tcp_endpoints = []
         vm.udp_endpoints = []
@@ -370,10 +385,12 @@ module Azure
         end
       end
 
-      def self.add_data_disk_to_xml(lun, media_link, options)
+      def self.add_data_disk_to_xml(vm, options)
         if options[:import] && options[:disk_name].nil?
           Loggerx.error_with_exit "The data disk name is not valid."
         end
+        media_link = vm.media_link
+        lun = options[:lun] || (Array(0..15) - vm.data_disks.map{|x| x[:lun].to_i}).first
         builder = Nokogiri::XML::Builder.new do |xml|
           xml.DataVirtualHardDisk(
             'xmlns' => 'http://schemas.microsoft.com/windowsazure',
@@ -383,7 +400,7 @@ module Azure
             xml.DiskLabel options[:disk_label]
             xml.DiskName options[:disk_name] if options[:import]
             xml.Lun lun
-            xml.LogicalDiskSizeInGB options[:disk_size] || 1
+            xml.LogicalDiskSizeInGB options[:disk_size] || 100
             unless options[:import]
               disk_name = media_link[/([^\/]+)$/]
               media_link = media_link.gsub(/#{disk_name}/, (Time.now.strftime('disk_%Y_%m_%d_%H_%M')) + '.vhd')
@@ -399,7 +416,7 @@ module Azure
       def self.port_already_opened?(existing_ports, port)
         return false if existing_ports.nil?
         raise "Port #{port} conflicts with a port already opened. "\
-              "Please select a different port." if existing_ports.include?(port)
+          "Please select a different port." if existing_ports.include?(port)
         false
       end
 

lib/azure/virtual_machine_management/virtual_machine.rb

@@ -36,6 +36,7 @@ module Azure
       attr_accessor :virtual_network_name
       attr_accessor :availability_set_name
       attr_accessor :media_link
+      attr_accessor :data_disks
     end
   end
 end

lib/azure/virtual_machine_management/virtual_machine_management_service.rb

@@ -377,8 +377,6 @@ module Azure
       #
       # * +cloud_service_name+  - String. Cloud service name.
       # * +vm_name+           - String. Virtual machine name.
-      # * +lun+                 - String. Specifies the Logical Unit Number
-      #   (LUN) for the disk. Valid LUN values are 0 through 15.
       # * +options+             - Hash. Optional parameters.
       #
       # ==== Options
@@ -392,16 +390,18 @@ module Azure
       #   The default is ReadOnly. Possible values are: None, ReadOnly, ReadWrite
       # * +:disk_label+    - String. Specifies the description of the data disk.
       # * +:disk_size+     - String. Specifies the size of disk in GB
+      # * +lun+                 - String. Specifies the Logical Unit Number
+      #   (LUN) for the disk. Valid LUN values are 0 through 15.
       #
       # See http://msdn.microsoft.com/en-us/library/windowsazure/jj157199.aspx
       #
       # Returns None
-      def add_data_disk(vm_name, cloud_service_name, lun, options = {})
+      def add_data_disk(vm_name, cloud_service_name, options = {})
         options[:import] ||= false
         vm = get_virtual_machine(vm_name, cloud_service_name)
         if vm
           path = "/services/hostedservices/#{cloud_service_name}/deployments/#{vm.deployment_name}/roles/#{vm_name}/DataDisks"
-          body = Serialization.add_data_disk_to_xml(lun, vm.media_link, options)
+          body = Serialization.add_data_disk_to_xml(vm, options)
           Loggerx.info "Adding data disk to virtual machine #{vm_name} ..."
           request = ManagementHttpRequest.new(:post, path, body)
           request.call

test/integration/vm/VM_Operations_test.rb

@@ -107,9 +107,8 @@ describe Azure::VirtualMachineManagementService do
 
     describe '#add_data_disk' do
       it 'add data disk to virtual machine' do
-        lun = rand(1..15)
         others = { disk_size: 100 }
-        subject.add_data_disk(vm_name, csn , lun, others)
+        subject.add_data_disk(vm_name, csn, others)
         dms = VirtualMachineDiskManagementService.new
         disks = dms.list_virtual_machine_disks
         disks = disks.select { |x| (/#{csn}/ =~ x.name) && x.os_type.empty? }

test/unit/virtual_machine_management/serialization_test.rb

@@ -169,22 +169,28 @@ describe Azure::VirtualMachineManagement::Serialization do
   describe '#add_data_disk_to_xml' do
 
     let(:options) do
-      {disk_size: 100}
+      {
+       disk_size: 100,
+       lun: 5
+      }
     end
     let(:media_link) { 'https://sta.blob.managment.core.net/vhds/1234.vhd' }
-    let(:lun) { 5 }
+
     before do
       Loggerx.expects(:puts).returns(nil).at_least(0)
+      @vm = Azure::VirtualMachineManagement::VirtualMachine.new
+      @vm.data_disks = []
+      @vm.media_link = media_link
     end
 
-    it 'returns an xml for newly created data disk' do
-      result = subject.add_data_disk_to_xml(lun, media_link, options)
+    it 'returns an xml for newly created data disk' do      
+      result = subject.add_data_disk_to_xml(@vm, options)
       doc = Nokogiri::XML(result)
       disk_size = doc.css('DataVirtualHardDisk LogicalDiskSizeInGB').text
       media_link = doc.css('DataVirtualHardDisk MediaLink').text
       disk_name = doc.css('DataVirtualHardDisk DiskName').text
       result.must_be_kind_of String
-      doc.css('DataVirtualHardDisk Lun').text.must_equal lun.to_s
+      doc.css('DataVirtualHardDisk Lun').text.must_equal options[:lun].to_s
       disk_size.must_equal options[:disk_size].to_s
       media_link.wont_be_empty
       disk_name.must_be_empty
@@ -192,13 +198,14 @@ describe Azure::VirtualMachineManagement::Serialization do
 
     it 'returns an xml for existing data disk' do
       options[:import] = true
+      options.delete(:lun)
       options[:disk_name] = 'disk_name'
-      result = subject.add_data_disk_to_xml(lun, media_link, options)
+      result = subject.add_data_disk_to_xml(@vm, options)
       doc = Nokogiri::XML(result)
       media_link = doc.css('DataVirtualHardDisk MediaLink').text
       disk_name = doc.css('DataVirtualHardDisk DiskName').text
       result.must_be_kind_of String
-      doc.css('DataVirtualHardDisk Lun').text.must_equal lun.to_s
+      doc.css('DataVirtualHardDisk Lun').text.must_equal '0'
       media_link.must_be_empty
       disk_name.wont_be_empty
     end
@@ -206,7 +213,7 @@ describe Azure::VirtualMachineManagement::Serialization do
     it 'raise error when disk name is empty' do
       options[:import] = true
       exception = assert_raises(RuntimeError) do
-        subject.add_data_disk_to_xml(lun, media_link, options)
+        subject.add_data_disk_to_xml(@vm, options)
       end
       assert_match(/The data disk name is not valid/i, exception.message)
     end