Fixed a bug for Get-AzKeyVaultSecret -AsPlainText (#14661)

Co-authored-by: Beisi Zhou <[email protected]>

Author: BethanyZhou

src/KeyVault/KeyVault.Test/PesterTests/Secret.Tests.ps1

@@ -15,5 +15,6 @@ Describe "Get secret" {
         $versions = Get-AzKeyVaultSecret -VaultName $vaultName -Name $secretName -IncludeVersions
         Get-AzKeyVaultSecret -VaultName $vaultName -Name $secretName -Version $versions[0].Version -AsPlainText | Should -BeExactly $secretTextV2
         Get-AzKeyVaultSecret -VaultName $vaultName -Name $secretName -Version $versions[1].Version -AsPlainText | Should -BeExactly $secretText
+        Get-AzKeyVaultSecret -VaultName $vaultName -Name "doesnotexist" -AsPlainText | Should -BeNullOrEmpty
     }
 }

src/KeyVault/KeyVault/ChangeLog.md

@@ -18,6 +18,7 @@
         - Additional information about change #1
 -->
 ## Upcoming Release
+* Fixed a bug for `Get-AzKeyVaultSecret -AsPlainText` if the secret is not found [#14645]
 
 ## Version 3.4.1
 * Supported upcoming new API design for `Export-AzKeyVaultSecurityDomain`

src/KeyVault/KeyVault/Commands/GetAzureKeyVaultSecret.cs

@@ -284,7 +284,7 @@ private void WriteSecret(PSKeyVaultSecret secret)
         {
             if (AsPlainText)
             {
-                WriteObject(ConvertFromSecureString(secret.SecretValue));
+                WriteObject(ConvertFromSecureString(secret?.SecretValue));
             }
             else
             {
@@ -294,6 +294,10 @@ private void WriteSecret(PSKeyVaultSecret secret)
 
         private string ConvertFromSecureString(SecureString secretValue)
         {
+            if(secretValue == null)
+            {
+                return null;
+            }
             var ssPtr = Marshal.SecureStringToBSTR(secretValue);
             try
             {