Remove config disk support

Originally added in response to issue #472, which doesn't have a lot of details, but does mention
Virtual Machine Scale Sets. This doesn't seem to be a fully implemented feature and there is no
recent progress on making a real feature.

The config disk code is current breaking due to new api changes introduce as part of PR #674
Rather than fix those failures, it makes more sense to remove an unused feature.

src/bosh_azure_cpi/.rubocop_todo.yml

@@ -451,7 +451,6 @@ Style/OpenStructUse:
     - 'spec/manual_tests/performance/upload_image.rb'
     - 'spec/manual_tests/resource_group_name/helpers.rb'
     - 'spec/unit/bosh_release/jobs/cpi/templates/cpi.json.erb_spec.rb'
-    - 'spec/unit/vm_manager/create/use_config_disk_spec.rb'
 
 # Offense count: 4
 # Configuration parameters: AllowedMethods.

src/bosh_azure_cpi/lib/cloud/azure.rb

@@ -84,7 +84,6 @@ module AzureCloud; end
 require 'cloud/azure/disk/vhd_utils'
 require 'cloud/azure/storage/blob_manager'
 require 'cloud/azure/disk/disk_manager'
-require 'cloud/azure/disk/config_disk_manager'
 require 'cloud/azure/stemcell/stemcell_manager'
 require 'cloud/azure/meta_store/meta_store'
 require 'cloud/azure/meta_store/stemcell_meta'

src/bosh_azure_cpi/lib/cloud/azure/cloud.rb

@@ -838,8 +838,7 @@ def _init_azure
       @disk_manager2           = Bosh::AzureCloud::DiskManager2.new(@azure_client)
       @stemcell_manager2       = Bosh::AzureCloud::StemcellManager2.new(@blob_manager, @meta_store, @storage_account_manager, @azure_client)
       @light_stemcell_manager  = Bosh::AzureCloud::LightStemcellManager.new(@blob_manager, @storage_account_manager, @azure_client)
-      @config_disk_manager     = Bosh::AzureCloud::ConfigDiskManager.new(@blob_manager, @disk_manager2, @storage_account_manager)
-      @vm_manager              = Bosh::AzureCloud::VMManager.new(_azure_config, @registry.endpoint, @disk_manager, @disk_manager2, @azure_client, @storage_account_manager, @stemcell_manager, @stemcell_manager2, @light_stemcell_manager, @config_disk_manager)
+      @vm_manager              = Bosh::AzureCloud::VMManager.new(_azure_config, @registry.endpoint, @disk_manager, @disk_manager2, @azure_client, @storage_account_manager, @stemcell_manager, @stemcell_manager2, @light_stemcell_manager)
       @instance_type_mapper    = Bosh::AzureCloud::InstanceTypeMapper.new
     rescue Net::OpenTimeout => e
       cloud_error("Please make sure the CPI has proper network access to Azure. #{e.inspect}") # TODO: Will it throw the error when initializing the client and manager

src/bosh_azure_cpi/lib/cloud/azure/models/config.rb

@@ -60,15 +60,6 @@ def initialize(azure_stack_config_hash)
     end
   end
 
-  # TODO: Refactoring: Move class to new file: ConfigDisk
-  class ConfigDisk
-    attr_reader :enabled
-
-    def initialize(config_disk_config_hash)
-      @enabled = config_disk_config_hash['enabled']
-    end
-  end
-
   # TODO: Refactoring: Move class to new file: AzureConfig
   class AzureConfig
     include Helpers
@@ -84,7 +75,6 @@ class AzureConfig
     attr_reader :pip_idle_timeout_in_minutes
     attr_reader :parallel_upload_thread_num
     attr_reader :ssh_user, :ssh_public_key
-    attr_reader :config_disk
     attr_reader :stemcell_api_version
     attr_reader :use_default_account_for_cleaning
 
@@ -127,8 +117,6 @@ def initialize(azure_config_hash)
       @ssh_user = azure_config_hash['ssh_user']
       @ssh_public_key = azure_config_hash['ssh_public_key']
 
-      @config_disk = ConfigDisk.new(azure_config_hash.fetch('config_disk', 'enabled' => false))
-
       # Flag to skip looping all storage account in subscription
       @use_default_account_for_cleaning = false
       @use_default_account_for_cleaning = azure_config_hash['use_default_account_for_cleaning'] unless azure_config_hash['use_default_account_for_cleaning'].nil?

src/bosh_azure_cpi/lib/cloud/azure/models/disk_id.rb

@@ -57,7 +57,7 @@ def disk_name
     end
 
     def caching
-      invalid = !disk_name.start_with?(DATA_DISK_PREFIX, MANAGED_DATA_DISK_PREFIX, MANAGED_CONFIG_DISK_PREFIX)
+      invalid = !disk_name.start_with?(DATA_DISK_PREFIX, MANAGED_DATA_DISK_PREFIX)
       cloud_error('This function should only be called for data disks') if invalid
 
       return _parse_data_disk_caching_plain(@plain_id) unless @plain_id.nil?

src/bosh_azure_cpi/lib/cloud/azure/restapi/azure_client.rb

@@ -435,18 +435,6 @@ def create_virtual_machine(resource_group_name, vm_params, network_interfaces, a
         end
       end
 
-      unless vm_params[:config_disk].nil?
-        # append the config disk into the vm.
-        vm['properties']['storageProfile']['dataDisks'] = [] if vm['properties']['storageProfile']['dataDisks'].nil?
-        vm['properties']['storageProfile']['dataDisks'].push(
-          'lun' => 1,
-          'createOption' => 'Attach',
-          'managedDisk' => {
-            'id' => vm_params[:config_disk][:id].to_s
-          }
-        )
-      end
-
       unless availability_set.nil?
         vm['properties']['availabilitySet'] = {
           'id' => availability_set[:id]

src/bosh_azure_cpi/lib/cloud/azure/utils/bosh_agent_util.rb

@@ -46,10 +46,10 @@ def encode_user_data(user_data)
       Base64.strict_encode64(JSON.dump(user_data))
     end
 
-    # Obtain the full VM metadata to write in config disk or custom data.
+    # Obtain the full VM metadata to write custom data.
     #
     # As of CPI API version 2, and stemcell API version 2, the registry is bypassed.
-    # The agent settings are written directly to config disk if used, or the VM's custom data.
+    # The agent settings are written directly to the VM's custom data.
     # The stemcell API version is used to determine compatibility with the agent on the stemcell.
     # An updated agent will read the base metadata, and additionally the agent settings, bypassing the registry.
     def user_data_obj(registry_endpoint, instance_id, dns, agent_id, network_spec, environment, vm_params, config, computer_name = nil)
@@ -88,7 +88,7 @@ def meta_data_obj(instance_id, ssh_public_key)
     #
     # Note:
     # As of CPI API version 2, and stemcell API version 2, the registry is bypassed.
-    # The agent settings are written directly to config disk if used, or the VM's custom data.
+    # The agent settings are written directly to the VM's custom data.
     #
     # @param [String] agent_id Agent id (will be picked up by agent to
     #   assume its identity

src/bosh_azure_cpi/lib/cloud/azure/utils/helpers.rb

@@ -114,7 +114,6 @@ module Helpers
     DATA_DISK_PREFIX                = 'bosh-data'
     MANAGED_OS_DISK_PREFIX          = 'bosh-disk-os'
     MANAGED_DATA_DISK_PREFIX        = 'bosh-disk-data'
-    MANAGED_CONFIG_DISK_PREFIX      = 'bosh-cfg-disk'
     EPHEMERAL_DISK_POSTFIX          = 'ephemeral-disk'
     STEMCELL_PREFIX                 = 'bosh-stemcell'
     LIGHT_STEMCELL_PREFIX           = 'bosh-light-stemcell'

src/bosh_azure_cpi/lib/cloud/azure/vms/vm_manager.rb

@@ -4,10 +4,9 @@ module Bosh::AzureCloud
   class VMManager # rubocop:todo Metrics/ClassLength
     include Helpers
 
-    def initialize(azure_config, registry_endpoint, disk_manager, disk_manager2, azure_client, storage_account_manager, stemcell_manager, stemcell_manager2, light_stemcell_manager, config_disk_manager = nil)
+    def initialize(azure_config, registry_endpoint, disk_manager, disk_manager2, azure_client, storage_account_manager, stemcell_manager, stemcell_manager2, light_stemcell_manager)
       @azure_config = azure_config
       @registry_endpoint = registry_endpoint
-      @config_disk_manager = config_disk_manager
       @disk_manager = disk_manager
       @disk_manager2 = disk_manager2
       @azure_client = azure_client
@@ -156,16 +155,7 @@ def create(bosh_vm_meta, location, vm_props, disk_cids, network_configurator, en
         vm_params[:ssh_username]  = @azure_config.ssh_user
         vm_params[:ssh_cert_data] = @azure_config.ssh_public_key
         user_data = agent_settings.user_data_obj(@registry_endpoint, instance_id.to_s, network_configurator.default_dns, bosh_vm_meta.agent_id, network_spec, env, vm_params, config)
-        if @azure_config.config_disk.enabled
-          meta_data_obj = agent_settings.meta_data_obj(
-            instance_id.to_s,
-            @azure_config.ssh_public_key
-          )
-          config_disk = @config_disk_manager.prepare_config_disk(resource_group_name, vm_name, location, meta_data_obj, user_data)
-          vm_params[:config_disk] = config_disk
-        else
-          vm_params[:custom_data] = agent_settings.encode_user_data(user_data)
-        end
+        vm_params[:custom_data] = agent_settings.encode_user_data(user_data)
       when 'windows'
         # Generate secure random strings as username and password for Windows VMs
         # Users do not use this credential to logon to Windows VMs
@@ -211,8 +201,6 @@ def create(bosh_vm_meta, location, vm_props, disk_cids, network_configurator, en
             ephemeral_disk_name = @disk_manager2.generate_ephemeral_disk_name(vm_name)
             error_message += "\t Managed Ephemeral Disk: #{ephemeral_disk_name}\n"
           end
-
-          # TODO: Output message to delete config disk
         else
           storage_account_name = instance_id.storage_account_name
           os_disk_name = @disk_manager.generate_os_disk_name(vm_name)
@@ -266,8 +254,6 @@ def create(bosh_vm_meta, location, vm_props, disk_cids, network_configurator, en
             end
           )
 
-          # TODO: delete the config disk.
-
           tasks.map(&:wait)
           tasks.map(&:wait!)
         rescue StandardError => error

src/bosh_azure_cpi/spec/spec_helper.rb

@@ -73,10 +73,7 @@ def mock_cloud_options
         'default_security_group' => MOCK_DEFAULT_SECURITY_GROUP,
         'debug_mode' => false,
         'use_managed_disks' => false,
-        'request_id' => MOCK_REQUEST_ID,
-        'config_disk' => {
-          'enabled' => false
-        }
+        'request_id' => MOCK_REQUEST_ID
       },
       'registry' => {
         'endpoint' => 'localhost:42288',