Implemented Get-AzureRmVMChefExtension command

Author: nimisha

src/ResourceManager/Compute/Commands.Compute/Commands.Compute.csproj

@@ -234,6 +234,7 @@
     <Compile Include="Extension\AzureVMBackup\SetAzureVMBackupExtension.cs" />
     <Compile Include="Extension\BGInfo\SetAzureVMBGInfoExtension.cs" />
     <Compile Include="Extension\BGInfo\VirtualMachineBGInfoExtensionContext.cs" />
+    <Compile Include="Extension\Chef\GetAzureRmVMChefExtension.cs" />
     <Compile Include="Extension\Chef\RemoveAzureRmVMChefExtension.cs" />
     <Compile Include="Extension\Chef\SetAzureVMChefExtension.cs" />
     <Compile Include="Extension\CustomScript\GetAzureVMCustomScriptExtensionCommand.cs" />

src/ResourceManager/Compute/Commands.Compute/Extension/Chef/GetAzureRmVMChefExtension.cs

@@ -0,0 +1,125 @@
+using System;
+using System.Linq;
+using System.Management.Automation;
+using Microsoft.Azure.Commands.Compute.Common;
+using Microsoft.Azure.Commands.Compute.Models;
+using Microsoft.Azure.Management.Compute;
+using Microsoft.Azure.Management.Compute.Models;
+using Microsoft.Rest.Azure;
+
+namespace Microsoft.Azure.Commands.Compute.Extension.Chef
+{
+    [Cmdlet(
+        VerbsCommon.Get,
+        ProfileNouns.VirtualMachineChefExtension),
+    OutputType(
+        typeof(PSVirtualMachineExtension))]
+    public class GetAzureRmVMChefExtension : VirtualMachineExtensionBaseCmdlet
+    {
+        private string ExtensionDefaultPublisher = "Chef.Bootstrap.WindowsAzure";
+        private string ExtensionDefaultName = "ChefClient";
+        private string LinuxExtensionName = "LinuxChefClient";
+
+        protected const string LinuxParameterSetName = "Linux";
+        protected const string WindowsParameterSetName = "Windows";
+
+        [Parameter(
+           Mandatory = true,
+           Position = 0,
+           ValueFromPipelineByPropertyName = true,
+           HelpMessage = "The resource group name.")]
+        [ValidateNotNullOrEmpty]
+        public string ResourceGroupName { get; set; }
+
+        [Alias("ResourceName")]
+        [Parameter(
+            Mandatory = true,
+            Position = 1,
+            ValueFromPipelineByPropertyName = true,
+            HelpMessage = "The virtual machine name.")]
+        [ValidateNotNullOrEmpty]
+        public string VMName { get; set; }
+
+        [Alias("ExtensionName")]
+        [Parameter(
+            Mandatory = false,
+            Position = 2,
+            ValueFromPipelineByPropertyName = true,
+            HelpMessage = "Extension Name.")]
+        public string Name { get; set; }
+
+        [Parameter(
+            Position = 3,
+            ValueFromPipelineByPropertyName = true,
+            HelpMessage = "To show the status.")]
+        [ValidateNotNullOrEmpty]
+        public SwitchParameter Status { get; set; }
+
+        [Parameter(
+            Mandatory = true,
+            ParameterSetName = LinuxParameterSetName,
+            HelpMessage = "Set extension for Linux.")]
+        public SwitchParameter Linux { get; set; }
+
+        [Parameter(
+            Mandatory = true,
+            ParameterSetName = WindowsParameterSetName,
+            HelpMessage = "Set extension for Windows.")]
+        public SwitchParameter Windows { get; set; }
+
+        public override void ExecuteCmdlet()
+        {
+            base.ExecuteCmdlet();
+
+            if (this.Linux.IsPresent)
+            {
+                this.Name = LinuxExtensionName;
+            }
+            else if (this.Windows.IsPresent)
+            {
+                this.Name = ExtensionDefaultName;
+            }
+
+            ExecuteClientAction(() =>
+            {
+                if (string.IsNullOrEmpty(this.Name))
+                {
+                    var virtualMachine = ComputeClient.ComputeManagementClient.VirtualMachines.Get(this.ResourceGroupName, this.VMName);
+                    var chefExtension = virtualMachine.Resources != null
+                            ? virtualMachine.Resources.FirstOrDefault(extension =>
+                                extension.Publisher.Equals(ExtensionDefaultPublisher, StringComparison.InvariantCultureIgnoreCase) &&
+                                extension.VirtualMachineExtensionType.Equals(this.Name, StringComparison.InvariantCultureIgnoreCase))
+                            : null;
+
+                    if (chefExtension == null)
+                    {
+                        WriteObject(null);
+                        return;
+                    }
+                    else
+                    {
+                        this.Name = chefExtension.Name;
+                    }
+                }
+
+                AzureOperationResponse<VirtualMachineExtension> virtualMachineExtensionGetResponse = null;
+                if (Status.IsPresent)
+                {
+                    virtualMachineExtensionGetResponse =
+                        this.VirtualMachineExtensionClient.GetWithInstanceView(this.ResourceGroupName,
+                            this.VMName, this.Name);
+                }
+                else
+                {
+                    virtualMachineExtensionGetResponse = this.VirtualMachineExtensionClient.GetWithHttpMessagesAsync(
+                        this.ResourceGroupName,
+                        this.VMName,
+                        this.Name).GetAwaiter().GetResult();
+                }
+
+                var returnedExtension = virtualMachineExtensionGetResponse.ToPSVirtualMachineExtension(this.ResourceGroupName);
+                WriteObject(returnedExtension);
+            });
+        }
+    }
+}