Merge pull request #6860 from ethanmoffat/etmoffat/subnet_better_errormsg

Add a better error message when attempting to get a subnet that doesn't exist

Author: markcowl

src/ResourceManager/Network/Commands.Network.Test/ScenarioTests/VirtualNetworkTests.ps1

@@ -150,16 +150,29 @@ function Test-subnetCRUD
         Assert-AreEqual $subnetName $vnetExpected.Subnets[0].Name
         Assert-AreEqual $subnet2Name $vnetExpected.Subnets[1].Name
         Assert-AreEqual "10.0.3.0/24" $vnetExpected.Subnets[1].AddressPrefix
-        
+
         # Get subnet
         $subnet2 = Get-AzureRmvirtualNetwork -Name $vnetName -ResourceGroupName $rgname | Get-AzureRmVirtualNetworkSubnetConfig -Name $subnet2Name
         $subnetAll = Get-AzureRmvirtualNetwork -Name $vnetName -ResourceGroupName $rgname | Get-AzureRmVirtualNetworkSubnetConfig
-        
+
         Assert-AreEqual 2 @($subnetAll).Count
         Assert-AreEqual $subnetName $subnetAll[0].Name
         Assert-AreEqual $subnet2Name $subnetAll[1].Name
         Assert-AreEqual $subnet2Name $subnet2.Name
 
+        # Get non-existing subnet
+        try
+        {
+            $subnetNotExists = $vnetExpected | Get-AzureRmVirtualNetworkSubnetConfig -Name "Subnet-DoesNotExist"
+        }
+        catch
+        {
+            if ($_.Exception.GetType() -ne [System.ArgumentException])
+            {
+                throw;
+            }
+        }
+
         # Remove a subnet
         Get-AzureRmvirtualNetwork -Name $vnetName -ResourceGroupName $rgname | Remove-AzureRmVirtualNetworkSubnetConfig -Name $subnet2Name | Set-AzureRmVirtualNetwork
 

src/ResourceManager/Network/Commands.Network/ChangeLog.md

@@ -26,6 +26,7 @@
 * Added example for Set-AzureRmVirtualNetworkGatewayConnectionSharedKey
 * Added example for Set-AzureRmVirtualNetworkGatewayConnection
 * Re-generated cmdlets for ApplicationSecurityGroup, RouteTable and Usage using latest code generator
+* Clarified error message for Get-AzureRmVirtualNetworkSubnetConfig when attempting to get a subnet that does not exitc
 
 ## Version 6.4.1
 * Updated all help files to include full parameter types and correct input/output types.

src/ResourceManager/Network/Commands.Network/VirtualNetwork/Subnet/GetAzureVirtualNetworkSubnetConfigCommand.cs

@@ -13,6 +13,7 @@
 // ----------------------------------------------------------------------------------
 
 using Microsoft.Azure.Commands.Network.Models;
+using System;
 using System.Linq;
 using System.Management.Automation;
 
@@ -34,14 +35,18 @@ public class GetAzureVirtualNetworkSubnetConfigCommand : NetworkBaseCmdlet
 
         public override void Execute()
         {
-
             base.Execute();
             if (!string.IsNullOrEmpty(this.Name))
             {
                 var subnet =
-                    this.VirtualNetwork.Subnets.First(
+                    this.VirtualNetwork.Subnets.FirstOrDefault(
                         resource =>
-                            string.Equals(resource.Name, this.Name, System.StringComparison.CurrentCultureIgnoreCase));
+                            string.Equals(resource.Name, this.Name, StringComparison.CurrentCultureIgnoreCase));
+
+                if (subnet == null)
+                {
+                    throw new ArgumentException(string.Format(Properties.Resources.ResourceNotFound, this.Name));
+                }
 
                 WriteObject(subnet);
             }
@@ -50,7 +55,6 @@ public override void Execute()
                 var subnets = this.VirtualNetwork.Subnets;
                 WriteObject(subnets, true);
             }
-
         }
     }
 }