PowerShell · daxian-dbw · Feb 14, 2023 · Jan 5, 2023 · Jan 5, 2023 · Jan 5, 2023
diff --git a/...owerShell.Commands.Utility/commands/utility/WebCmdlet/Common/WebRequestPSCmdlet.Common.cs b/...owerShell.Commands.Utility/commands/utility/WebCmdlet/Common/WebRequestPSCmdlet.Common.cs
@@ -351,6 +351,12 @@ public virtual string CustomMethod
 
         private string _custommethod;
 
+        /// <summary>
+        /// Gets or sets the PreserveHttpMethodOnRedirect property.
+        /// </summary>
+        [Parameter]
+        public virtual SwitchParameter PreserveHttpMethodOnRedirect { get; set; }
+
         #endregion Method
 
         #region NoProxy
@@ -509,7 +515,7 @@ protected override void ProcessRecord()
                 bool keepAuthorizationOnRedirect = PreserveAuthorizationOnRedirect.IsPresent
                                                    && WebSession.Headers.ContainsKey(HttpKnownHeaderNames.Authorization);
 
-                bool handleRedirect = keepAuthorizationOnRedirect || AllowInsecureRedirect;
+                bool handleRedirect = keepAuthorizationOnRedirect || AllowInsecureRedirect || PreserveHttpMethodOnRedirect;
 
                 using (HttpClient client = GetHttpClient(handleRedirect))
                 {
@@ -1239,9 +1245,8 @@ internal virtual HttpResponseMessage GetResponse(HttpClient client, HttpRequestM
                     }
 
                     // For selected redirects, GET must be used with the redirected Location.
-                    if (currentRequest.Method == HttpMethod.Post && IsRedirectToGet(response.StatusCode))
+                    if (RequestRequiresForceGet(response.StatusCode, currentRequest.Method) && !PreserveHttpMethodOnRedirect)
                     {
-                        // See https://msdn.microsoft.com/library/system.net.httpstatuscode(v=vs.110).aspx
                         Method = WebRequestMethod.Get;
                         CustomMethod = string.Empty;
                     }
@@ -1713,7 +1718,7 @@ private static StreamContent GetMultipartStreamContent(object fieldName, Stream
         private static StreamContent GetMultipartFileContent(object fieldName, FileInfo file)
         {
             StreamContent result = GetMultipartStreamContent(fieldName: fieldName, stream: new FileStream(file.FullName, FileMode.Open));
-            
+
             // .NET does not enclose field names in quotes, however, modern browsers and curl do.
             result.Headers.ContentDisposition.FileName = "\"" + file.Name + "\"";
 
@@ -1773,43 +1778,34 @@ private static string FormatErrorMessage(string error, string contentType)
         }
 
         // Returns true if the status code is one of the supported redirection codes.
-        private static bool IsRedirectCode(HttpStatusCode code)
+        private static bool IsRedirectCode(HttpStatusCode statusCode) => statusCode switch
         {
-            int intCode = (int)code;
-            return
-            (
-                (intCode >= 300 && intCode < 304) ||
-                intCode == 307 ||
-                intCode == 308
-            );
-        }
+            HttpStatusCode.Found
+            or HttpStatusCode.Moved
+            or HttpStatusCode.MultipleChoices
+            or HttpStatusCode.PermanentRedirect
+            or HttpStatusCode.SeeOther
+            or HttpStatusCode.TemporaryRedirect => true,
+            _ => false
+        };
 
-        // Returns true if the status code is a redirection code and the action requires switching from POST to GET on redirection.
-        // NOTE: Some of these status codes map to the same underlying value but spelling them out for completeness.
-        private static bool IsRedirectToGet(HttpStatusCode code)
+        // Returns true if the status code is a redirection code and the action requires switching to GET on redirection.
+        // See https://learn.microsoft.com/en-us/dotnet/api/system.net.httpstatuscode
+        private static bool RequestRequiresForceGet(HttpStatusCode statusCode, HttpMethod requestMethod) => statusCode switch
         {
-            return
-            (
-                code == HttpStatusCode.Found ||
-                code == HttpStatusCode.Moved ||
-                code == HttpStatusCode.Redirect ||
-                code == HttpStatusCode.RedirectMethod ||
-                code == HttpStatusCode.SeeOther ||
-                code == HttpStatusCode.Ambiguous ||
-                code == HttpStatusCode.MultipleChoices
-            );
-        }
+            HttpStatusCode.Found
+            or HttpStatusCode.Moved
+            or HttpStatusCode.MultipleChoices => requestMethod == HttpMethod.Post,
+            HttpStatusCode.SeeOther => requestMethod != HttpMethod.Get && requestMethod != HttpMethod.Head,
+            _ => false
+        };
 
         // Returns true if the status code shows a server or client error and MaximumRetryCount > 0
-        private bool ShouldRetry(HttpStatusCode code)
+        private static bool ShouldRetry(HttpStatusCode statusCode) => (int)statusCode switch
         {
-            int intCode = (int)code;
-
-            return
-            (
-                (intCode == 304 || (intCode >= 400 && intCode <= 599)) && WebSession.MaximumRetryCount > 0
-            );
-        }
+            304 or (>= 400 and <= 599) => true,
+            _ => false
+        };
 
         private static HttpMethod GetHttpMethod(WebRequestMethod method) => method switch
         {

diff --git a/test/powershell/Modules/Microsoft.PowerShell.Utility/WebCmdlets.Tests.ps1 b/test/powershell/Modules/Microsoft.PowerShell.Utility/WebCmdlets.Tests.ps1
@@ -139,6 +139,9 @@ function ExecuteRedirectRequest {
         [switch]
         $PreserveAuthorizationOnRedirect,
 
+        [switch]
+        $PreserveHttpMethodOnRedirect,
+
         [ValidateRange(0, [int]::MaxValue)]
         [int]
         $MaximumRedirection
@@ -153,7 +156,7 @@ function ExecuteRedirectRequest {
             } elseif ($CustomMethod) {
                 $result.Output = Invoke-WebRequest -Uri $uri -Headers $headers -PreserveAuthorizationOnRedirect:$PreserveAuthorizationOnRedirect.IsPresent -CustomMethod $CustomMethod
             } else {
-                $result.Output = Invoke-WebRequest -Uri $uri -Headers $headers -PreserveAuthorizationOnRedirect:$PreserveAuthorizationOnRedirect.IsPresent -Method $Method
+                $result.Output = Invoke-WebRequest -Uri $uri -Headers $headers -PreserveAuthorizationOnRedirect:$PreserveAuthorizationOnRedirect.IsPresent -PreserveHttpMethodOnRedirect:$PreserveHttpMethodOnRedirect.IsPresent -Method $Method
             }
             $result.Content = $result.Output.Content | ConvertFrom-Json
         } else {
@@ -162,7 +165,7 @@ function ExecuteRedirectRequest {
             } elseif ($CustomMethod) {
                 $result.Output = Invoke-RestMethod -Uri $uri -Headers $headers -PreserveAuthorizationOnRedirect:$PreserveAuthorizationOnRedirect.IsPresent -CustomMethod $CustomMethod
             } else {
-                $result.Output = Invoke-RestMethod -Uri $uri -Headers $headers -PreserveAuthorizationOnRedirect:$PreserveAuthorizationOnRedirect.IsPresent -Method $Method
+                $result.Output = Invoke-RestMethod -Uri $uri -Headers $headers -PreserveAuthorizationOnRedirect:$PreserveAuthorizationOnRedirect.IsPresent -PreserveHttpMethodOnRedirect:$PreserveHttpMethodOnRedirect.IsPresent -Method $Method
             }
             # NOTE: $result.Output should already be a PSObject (Invoke-RestMethod converts the returned json automatically)
             # so simply reference $result.Output
@@ -1023,6 +1026,20 @@ Describe "Invoke-WebRequest tests" -Tags "Feature", "RequireAdminOnWindows" {
             $response.Content.Method | Should -Be $redirectedMethod
         }
 
+        It "Validates Invoke-WebRequest -PreserveHttpMethodOnRedirect keeps the authorization header redirects and do remains POST when it handles the redirect: <redirectType>" -TestCases $redirectTests {
+            param($redirectType)
+            $uri = Get-WebListenerUrl -Test 'Redirect' -Query @{type = $redirectType}
+            $response = ExecuteRedirectRequest -PreserveHttpMethodOnRedirect -Uri $uri -Method 'POST'
+
+            $response.Error | Should -BeNullOrEmpty
+            # ensure user-agent is present (i.e., no false positives )
+            $response.Content.Headers."User-Agent" | Should -Not -BeNullOrEmpty
+            # ensure Authorization header has been kept.
+            $response.Content.Headers."Authorization" | Should -BeExactly 'test'
+            # ensure POST doesn't change.
+            $response.Content.Method | Should -Be 'POST'
+        }
+
         It "Validates Invoke-WebRequest handles responses without Location header for requests with Authorization header and redirect: <redirectType>" -TestCases $redirectTests {
             param($redirectType, $redirectedMethod)
             # Skip relative test as it is not a valid response type.
@@ -2745,6 +2762,20 @@ Describe "Invoke-RestMethod tests" -Tags "Feature", "RequireAdminOnWindows" {
         $response.Content.Method | Should -Be $redirectedMethod
     }
 
+    It "Validates Invoke-RestMethod -PreserveHttpMethodOnRedirect keeps the authorization header redirects and remains POST when it handles the redirect: <redirectType>" -TestCases $redirectTests {
+        param($redirectType)
+        $uri = Get-WebListenerUrl -Test 'Redirect' -Query @{type = $redirectType}
+        $response = ExecuteRedirectRequest -PreserveHttpMethodOnRedirect -Cmdlet 'Invoke-RestMethod' -Uri $uri -Method 'POST'
+
+        $response.Error | Should -BeNullOrEmpty
+        # ensure user-agent is present (i.e., no false positives )
+        $response.Content.Headers."User-Agent" | Should -Not -BeNullOrEmpty
+        # ensure Authorization header has been kept.
+        $response.Content.Headers."Authorization" | Should -BeExactly 'test'
+        # ensure POST doesn't change.
+        $response.Content.Method | Should -Be 'POST'
+    }
+
     It "Validates Invoke-RestMethod handles responses without Location header for requests with Authorization header and redirect: <redirectType>" -TestCases $redirectTests {
         param($redirectType, $redirectedMethod)
         # Skip relative test as it is not a valid response type.