Merge pull request Azure#3849 from krkhan/backup_enc_settings_rebased

Backup encryption settings and restore on failure (Supersedes Azure#3824)

Author: cormacpayne

src/ResourceManager/Compute/ChangeLog.md

@@ -1,4 +1,4 @@
-<!--
+<!--
     Please leave this section at the top of the change log.
 
     Changes for the current release should go under the section titled "Current Release", and should adhere to the following format:
@@ -19,6 +19,8 @@
 -->
 ## Current Release
 
+* Backup encryption settings for IaaS VMs and restore on failure
+
 ## Version 2.9.0
 
 * Fix bug in Get-* cmdlets, to allow retrieving multiple pages of data (more than 120 items)

src/ResourceManager/Compute/Commands.Compute/Extension/AzureDiskEncryption/SetAzureDiskEncryptionExtension.cs

@@ -282,6 +282,14 @@ private AzureOperationResponse<VirtualMachine> UpdateVmEncryptionSettings()
                                                       null));
             }
 
+            DiskEncryptionSettings encryptionSettingsBackup = vmParameters.StorageProfile.OsDisk.EncryptionSettings;
+
+            if (encryptionSettingsBackup == null)
+            {
+                encryptionSettingsBackup = new DiskEncryptionSettings();
+                encryptionSettingsBackup.Enabled = false;
+            }
+
             DiskEncryptionSettings encryptionSettings = new DiskEncryptionSettings();
             encryptionSettings.Enabled = true;
             encryptionSettings.DiskEncryptionKey = new KeyVaultSecretReference();
@@ -306,10 +314,25 @@ private AzureOperationResponse<VirtualMachine> UpdateVmEncryptionSettings()
                 Location = vmParameters.Location,
                 Tags = vmParameters.Tags
             };
-            return this.ComputeClient.ComputeManagementClient.VirtualMachines.CreateOrUpdateWithHttpMessagesAsync(
+
+            AzureOperationResponse<VirtualMachine> updateResult = this.ComputeClient.ComputeManagementClient.VirtualMachines.CreateOrUpdateWithHttpMessagesAsync(
                 this.ResourceGroupName,
                 vmParameters.Name,
                 parameters).GetAwaiter().GetResult();
+
+            if(!updateResult.Response.IsSuccessStatusCode)
+            {
+                vmParameters = (this.ComputeClient.ComputeManagementClient.VirtualMachines.Get(
+                   this.ResourceGroupName, this.VMName));
+                vmParameters.StorageProfile.OsDisk.EncryptionSettings = encryptionSettingsBackup;
+
+                this.ComputeClient.ComputeManagementClient.VirtualMachines.CreateOrUpdateWithHttpMessagesAsync(
+                    this.ResourceGroupName,
+                    vmParameters.Name,
+                    parameters).GetAwaiter().GetResult();
+            }
+
+            return updateResult;
         }
 
         private Hashtable GetExtensionPublicSettings()
@@ -444,12 +467,23 @@ public override void ExecuteCmdlet()
 
                     VirtualMachineExtension parameters = GetVmExtensionParameters(virtualMachineResponse);
 
-                    this.VirtualMachineExtensionClient.CreateOrUpdateWithHttpMessagesAsync(
+                    AzureOperationResponse<VirtualMachineExtension> extensionPushResult = this.VirtualMachineExtensionClient.CreateOrUpdateWithHttpMessagesAsync(
                         this.ResourceGroupName,
                         this.VMName,
                         this.Name,
                         parameters).GetAwaiter().GetResult();
 
+                    if (!extensionPushResult.Response.IsSuccessStatusCode)
+                    {
+                        ThrowTerminatingError(new ErrorRecord(new ApplicationException(string.Format(CultureInfo.CurrentUICulture,
+                                                                                       "Installation failed for extension {0} with error {1}",
+                                                                                       parameters.VirtualMachineExtensionType,
+                                                                                       extensionPushResult.Response.Content.ReadAsStringAsync().GetAwaiter().GetResult())),
+                                                              "InvalidResult",
+                                                              ErrorCategory.InvalidResult,
+                                                              null));
+                    }
+
                     var op = UpdateVmEncryptionSettings();
                     var result = Mapper.Map<PSAzureOperationResponse>(op);
                     WriteObject(result);