Improvements in processing redirects with cookie containers.

src/RestSharp/KnownHeaders.cs

@@ -36,6 +36,7 @@ public static class KnownHeaders {
     public const string Cookie             = "Cookie";
     public const string SetCookie          = "Set-Cookie";
     public const string UserAgent          = "User-Agent";
+    public const string TransferEncoding   = "Transfer-Encoding";
 
     internal static readonly string[] ContentHeaders = {
         Allow, Expires, ContentDisposition, ContentEncoding, ContentLanguage, ContentLength, ContentLocation, ContentRange, ContentType, ContentMD5,

src/RestSharp/Options/RestClientOptions.cs

@@ -50,6 +50,12 @@ public RestClientOptions(string baseUrl) : this(new Uri(Ensure.NotEmptyString(ba
     /// <summary>
     /// Custom configuration for the underlying <seealso cref="HttpMessageHandler"/>
     /// </summary>
+    /// <remarks>
+    /// With the addition of all redirection processing being implemented directly by <see cref="RestClient"/>
+    /// please do not alter the <see cref="System.Net.Http.HttpClientHandler.AllowAutoRedirect"/> from its default supplied by RestClient.
+    /// If you set <see cref="System.Net.Http.HttpClientHandler.AllowAutoRedirect"/> to true, then redirection cookie
+    /// processing improvements in RestClient will be skipped since <see cref="System.Net.Http.HttpClient"/> will hide the details from us.
+    /// </remarks>
     public Func<HttpMessageHandler, HttpMessageHandler>? ConfigureMessageHandler { get; set; }
 
     /// <summary>
@@ -60,7 +66,7 @@ public RestClientOptions(string baseUrl) : this(new Uri(Ensure.NotEmptyString(ba
             ? ResponseStatus.Completed
             : ResponseStatus.Error;
 
-    /// <summary>
+    /// <summary>s
     /// Authenticator that will be used to populate request with necessary authentication data
     /// </summary>
     public IAuthenticator? Authenticator { get; set; }
@@ -86,7 +92,7 @@ public RestClientOptions(string baseUrl) : this(new Uri(Ensure.NotEmptyString(ba
     public bool UseDefaultCredentials { get; set; }
 
     /// <summary>
-    /// Set to true if you need the Content-Type not to have the charset 
+    /// Set to true if you need the Content-Type not to have the charset
     /// </summary>
     public bool DisableCharset { get; set; }
 
@@ -131,10 +137,25 @@ public RestClientOptions(string baseUrl) : this(new Uri(Ensure.NotEmptyString(ba
     /// </summary>
     public CacheControlHeaderValue? CachePolicy { get; set; }
 
+    /// <summary>
+    /// Policy settings for redirect processing
+    /// </summary>
+    public RestClientRedirectionOptions RedirectOptions { get; set; } = new RestClientRedirectionOptions();
+
     /// <summary>
     /// Instruct the client to follow redirects. Default is true.
     /// </summary>
-    public bool FollowRedirects { get; set; } = true;
+    /// <remarks>
+    /// Note: This now delegates the property implementation to <see cref="RestClientRedirectionOptions"/>.
+    /// </remarks>
+    public bool FollowRedirects {
+        get {
+            return RedirectOptions.FollowRedirects;
+        }
+        set {
+            RedirectOptions.FollowRedirects = value;
+        }
+    }
 
     /// <summary>
     /// Gets or sets a value that indicates if the <see langword="Expect" /> header for an HTTP request contains Continue.

src/RestSharp/Options/RestClientRedirectionOptions.cs

@@ -0,0 +1,143 @@
+using RestSharp.Extensions;
+using System.Net;
+using System.Reflection;
+
+namespace RestSharp;
+
+/// <summary>
+/// Options related to redirect processing.
+/// </summary>
+[GenerateImmutable]
+public class RestClientRedirectionOptions {
+    static readonly Version Version = new AssemblyName(typeof(RestClientOptions).Assembly.FullName!).Version!;
+
+    /// <summary>
+    /// Set to true (default), when you want to follow redirects
+    /// </summary>
+    public bool FollowRedirects { get; set; } = true;
+
+    /// <summary>
+    /// Set to true (default is false), when you want to follow a
+    /// redirect from HTTPS to HTTP.
+    /// </summary>
+    public bool FollowRedirectsToInsecure { get; set; } = false;
+
+    /// <summary>
+    /// Set to true (default), when you want to include the originally
+    /// requested headers in redirected requests.
+    /// </summary>
+    /// <remarks>NOTE: The 'Authorization' header is controlled by <see cref="ForwardAuthorization"/>,
+    /// and the 'Cookie' header is controlled by <see cref="ForwardCookies"/>.
+    /// </remarks>
+    public bool ForwardHeaders { get; set; } = true;
+
+    /// <summary>
+    /// Set to true (default is false), when you want to send the original
+    /// Authorization header to the redirected destination.
+    /// </summary>
+    public bool ForwardAuthorization { get; set; } = false;
+
+    /// <summary>
+    /// Set to true (default), when you want to include cookies from the
+    /// <see cref="CookieContainer"/> on the redirected URL.
+    /// </summary>
+    /// <remarks>
+    /// NOTE: The exact cookies sent to the redirected url DEPENDS directly
+    /// on the redirected url. A redirection to a completly differnet FQDN
+    /// for example is unlikely to actually propagate any cookies from the
+    /// <see cref="CookieContainer"/>.
+    /// </remarks>
+    public bool ForwardCookies { get; set; } = true;
+
+    /// <summary>
+    /// Set to true (default) in order to send the body to the
+    /// redirected URL, unless the force verb to GET behavior is triggered.
+    /// <see cref="ForceForwardBody"/>
+    /// </summary>
+    public bool ForwardBody { get; set; } = false;
+
+    /// <summary>
+    /// Set to true (default is false) to force forwarding the body of the
+    /// request even when normally, the verb might be altered to GET based
+    /// on backward compatiblity with browser processing of HTTP status codes.
+    /// </summary>
+    /// <remarks>
+    /// Based on Wikipedia https://en.wikipedia.org/wiki/HTTP_302:
+    /// <pre>
+    ///  Many web browsers implemented this code in a manner that violated this standard, changing
+    ///  the request type of the new request to GET, regardless of the type employed in the original request
+    ///  (e.g. POST). For this reason, HTTP/1.1 (RFC 2616) added the new status codes 303 and 307 to disambiguate
+    ///  between the two behaviours, with 303 mandating the change of request type to GET, and 307 preserving the
+    ///  request type as originally sent. Despite the greater clarity provided by this disambiguation, the 302 code
+    ///  is still employed in web frameworks to preserve compatibility with browsers that do not implement the HTTP/1.1
+    ///  specification.
+    /// </pre>
+    /// </remarks>
+    public bool ForceForwardBody { get; set; } = false;
+
+    /// <summary>
+    /// Set to true (default) to forward the query string to the redirected URL.
+    /// </summary>
+    public bool ForwardQuery { get; set; } = true;
+
+    /// <summary>
+    /// The maximum number of redirects to follow.
+    /// </summary>
+    public int MaxRedirects { get; set; } = 50;
+
+    /// <summary>
+    /// Set to true (default), to supply any requested fragment portion of the original URL to the destination URL.
+    /// </summary>
+    /// <remarks>
+    /// Per https://tools.ietf.org/html/rfc7231#section-7.1.2, a redirect location without a
+    /// fragment should inherit the fragment from the original URI.
+    /// </remarks>
+    public bool ForwardFragment { get; set; } = true;
+
+    /// <summary>
+    /// Set to true (default), to allow the HTTP Method used on the original request to
+    /// be replaced with GET when the status code 303 (HttpStatusCode.RedirectMethod)
+    /// was returned. Setting this to false will disallow the altering of the verb.
+    /// </summary>
+    public bool AllowRedirectMethodStatusCodeToAlterVerb { get; set; } = true;
+
+    /// <summary>
+    /// Set to true (default), to allow the backward compatibility behavior of
+    /// changing the verb to GET with non 303 redirection status codes.
+    /// </summary>
+    /// <remarks>
+    /// NOTE: Even though the below text only references 302, this also allows some other scenarios.
+    /// See <see cref="RestClient.RedirectRequestRequiresForceGet(HttpStatusCode, HttpMethod)"/> for the specifics.
+    /// Based on Wikipedia https://en.wikipedia.org/wiki/HTTP_302:
+    ///  Many web browsers implemented this code in a manner that violated this standard, changing
+    ///  the request type of the new request to GET, regardless of the type employed in the original request
+    ///  (e.g. POST). For this reason, HTTP/1.1 (RFC 2616) added the new status codes 303 and 307 to disambiguate
+    ///  between the two behaviours, with 303 mandating the change of request type to GET, and 307 preserving the
+    ///  request type as originally sent. Despite the greater clarity provided by this disambiguation, the 302 code
+    ///  is still employed in web frameworks to preserve compatibility with browsers that do not implement the HTTP/1.1
+    ///  specification.
+    /// </remarks>
+    public bool AllowForcedRedirectVerbChange { get; set; } = true;
+
+    /// <summary>
+    /// HttpStatusCodes that trigger redirect processing. Defaults to MovedPermanently (301),
+    /// SeeOther/RedirectMethod (303),
+    /// TemporaryRedirect (307),
+    /// Redirect (302),
+    /// PermanentRedirect (308)
+    /// </summary>
+    public IReadOnlyList<HttpStatusCode> RedirectStatusCodes { get; set; }
+
+    public RestClientRedirectionOptions() {
+        RedirectStatusCodes = new List<HttpStatusCode>() {
+            HttpStatusCode.MovedPermanently,
+            HttpStatusCode.SeeOther,
+            HttpStatusCode.TemporaryRedirect,
+            HttpStatusCode.Redirect,
+#if NET
+            HttpStatusCode.PermanentRedirect,
+#endif
+        }.AsReadOnly();
+    }
+}
+

src/RestSharp/Parameters/FileParameter.cs

@@ -114,6 +114,7 @@ public static FileParameter FromFile(
 [PublicAPI]
 public class FileParameterOptions {
     [Obsolete("Use DisableFilenameStar instead")]
+    [CLSCompliant(false)]
     public bool DisableFileNameStar {
         get => DisableFilenameStar;
         set => DisableFilenameStar = value;

src/RestSharp/Request/RequestContent.cs

@@ -1,11 +1,11 @@
 //  Copyright (c) .NET Foundation and Contributors
-// 
+//
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
-// 
+//
 // http://www.apache.org/licenses/LICENSE-2.0
-// 
+//
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -36,7 +36,7 @@ public RequestContent(RestClient client, RestRequest request) {
         _parameters = new RequestParameters(_request.Parameters.Union(_client.DefaultParameters));
     }
 
-    public HttpContent BuildContent() {
+    public HttpContent BuildContent(bool omitBody = false) {
         var postParameters       = _parameters.GetContentParameters(_request.Method).ToArray();
         var postParametersExists = postParameters.Length > 0;
         var bodyParametersExists = _request.TryGetBodyParameter(out var bodyParameter);
@@ -51,7 +51,7 @@ public HttpContent BuildContent() {
 
         if (filesExists) AddFiles();
 
-        if (bodyParametersExists) AddBody(postParametersExists, bodyParameter!);
+        if (bodyParametersExists && !omitBody) AddBody(postParametersExists, bodyParameter!);
 
         if (postParametersExists) AddPostParameters(postParameters);
 
@@ -83,7 +83,7 @@ StreamContent ToStreamContent(FileParameter fileParameter) {
         var dispositionHeader = fileParameter.Options.DisableFilenameEncoding
             ? ContentDispositionHeaderValue.Parse($"form-data; name=\"{fileParameter.Name}\"; filename=\"{fileParameter.FileName}\"")
             : new ContentDispositionHeaderValue("form-data") { Name = $"\"{fileParameter.Name}\"", FileName = $"\"{fileParameter.FileName}\"" };
-        if (!fileParameter.Options.DisableFileNameStar) dispositionHeader.FileNameStar = fileParameter.FileName;
+        if (!fileParameter.Options.DisableFilenameStar) dispositionHeader.FileNameStar = fileParameter.FileName;
         streamContent.Headers.ContentDisposition = dispositionHeader;
 
         return streamContent;

src/RestSharp/Request/UriExtensions.cs

@@ -37,10 +37,17 @@ public static Uri MergeBaseUrlAndResource(this Uri? baseUrl, string? resource) {
     public static Uri AddQueryString(this Uri uri, string? query) {
         if (query == null) return uri;
 
-        var absoluteUri       = uri.AbsoluteUri;
-        var separator = absoluteUri.Contains('?') ? "&" : "?";
-
-        return new Uri($"{absoluteUri}{separator}{query}");
+        var absoluteUri = uri.AbsoluteUri;
+        var fragment = string.Empty;
+        if (!string.IsNullOrEmpty(uri.Fragment)) {
+            int fragmentStartIndex = absoluteUri.LastIndexOf(uri.Fragment);
+            if (fragmentStartIndex != -1) {
+                fragment = absoluteUri.Substring(fragmentStartIndex, absoluteUri.Length - fragmentStartIndex);
+                absoluteUri = absoluteUri.Substring(0, fragmentStartIndex);
+            }
+        }
+        var separator = string.IsNullOrEmpty(uri.Query) ? "?" : "&"; //absoluteUri.Contains('?') ? "&" : "?";
+        return new Uri($"{absoluteUri}{separator}{query}{fragment}");
     }
 
     public static UrlSegmentParamsValues GetUrlSegmentParamsValues(