PowerShell · iSazonov · Apr 24, 2023 · Mar 16, 2023 · Mar 16, 2023 · Mar 16, 2023
diff --git a/...l.Commands.Utility/commands/utility/WebCmdlet/Common/BasicHtmlWebResponseObject.Common.cs b/...l.Commands.Utility/commands/utility/WebCmdlet/Common/BasicHtmlWebResponseObject.Common.cs
@@ -1,8 +1,11 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
 
+#nullable enable
+
 using System.Collections.Generic;
 using System.Diagnostics;
+using System.Diagnostics.CodeAnalysis;
 using System.IO;
 using System.Management.Automation;
 using System.Net.Http;
@@ -33,7 +36,7 @@ public BasicHtmlWebResponseObject(HttpResponseMessage response, CancellationToke
         /// <param name="response">The response.</param>
         /// <param name="contentStream">The content stream associated with the response.</param>
         /// <param name="cancellationToken">Cancellation token.</param>
-        public BasicHtmlWebResponseObject(HttpResponseMessage response, Stream contentStream, CancellationToken cancellationToken) : base(response, contentStream, cancellationToken)
+        public BasicHtmlWebResponseObject(HttpResponseMessage response, Stream? contentStream, CancellationToken cancellationToken) : base(response, contentStream, cancellationToken)
         {
             InitializeContent(cancellationToken);
             InitializeRawContent(response);
@@ -60,9 +63,9 @@ public BasicHtmlWebResponseObject(HttpResponseMessage response, Stream contentSt
         /// Encoding of the response body from the <c>Content-Type</c> header,
         /// or <see langword="null"/> if the encoding could not be determined.
         /// </value>
-        public Encoding Encoding { get; private set; }
+        public Encoding? Encoding { get; private set; }
 
-        private WebCmdletElementCollection _inputFields;
+        private WebCmdletElementCollection? _inputFields;
 
         /// <summary>
         /// Gets the HTML input field elements parsed from <see cref="Content"/>.
@@ -87,7 +90,7 @@ public WebCmdletElementCollection InputFields
             }
         }
 
-        private WebCmdletElementCollection _links;
+        private WebCmdletElementCollection? _links;
 
         /// <summary>
         /// Gets the HTML a link elements parsed from <see cref="Content"/>.
@@ -112,7 +115,7 @@ public WebCmdletElementCollection Links
             }
         }
 
-        private WebCmdletElementCollection _images;
+        private WebCmdletElementCollection? _images;
 
         /// <summary>
         /// Gets the HTML img elements parsed from <see cref="Content"/>.
@@ -145,13 +148,14 @@ public WebCmdletElementCollection Images
         /// Reads the response content from the web response.
         /// </summary>
         /// <param name="cancellationToken">The cancellation token.</param>
+        [MemberNotNull(nameof(Content))]
         protected void InitializeContent(CancellationToken cancellationToken)
         {
-            string contentType = ContentHelper.GetContentType(BaseResponse);
+            string? contentType = ContentHelper.GetContentType(BaseResponse);
             if (ContentHelper.IsText(contentType))
             {
                 // Fill the Content buffer
-                string characterSet = WebResponseHelper.GetCharacterSet(BaseResponse);
+                string? characterSet = WebResponseHelper.GetCharacterSet(BaseResponse);
 
                 Content = StreamHelper.DecodeStream(RawContentStream, characterSet, out Encoding encoding, cancellationToken);
                 Encoding = encoding;
@@ -204,7 +208,7 @@ private static void ParseAttributes(string outerHtml, PSObject elementObject)
                     string name = nvMatches.Groups[1].Value;
 
                     // The value (if any) is captured by group #2, #3, or #4, depending on quoting or lack thereof
-                    string value = null;
+                    string? value = null;
                     if (nvMatches.Groups[2].Success)
                     {
                         value = nvMatches.Groups[2].Value;

diff --git a/...oft.PowerShell.Commands.Utility/commands/utility/WebCmdlet/Common/ContentHelper.Common.cs b/...oft.PowerShell.Commands.Utility/commands/utility/WebCmdlet/Common/ContentHelper.Common.cs
@@ -1,7 +1,10 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
 
+#nullable enable
+
 using System;
+using System.Diagnostics.CodeAnalysis;
 using System.Management.Automation;
 using System.Net.Http;
 using System.Net.Http.Headers;
@@ -16,7 +19,7 @@ internal static class ContentHelper
         #region Internal Methods
 
         // ContentType may not exist in response header.  Return null if not.
-        internal static string GetContentType(HttpResponseMessage response) => response.Content.Headers.ContentType?.MediaType;
+        internal static string? GetContentType(HttpResponseMessage response) => response.Content.Headers.ContentType?.MediaType;
 
         internal static Encoding GetDefaultEncoding() => Encoding.UTF8;
 
@@ -35,7 +38,7 @@ internal static StringBuilder GetRawContentHeader(HttpResponseMessage response)
             HttpHeaders[] headerCollections =
             {
                 response.Headers,
-                response.Content?.Headers
+                response.Content.Headers
             };
 
             foreach (var headerCollection in headerCollections)
@@ -59,7 +62,7 @@ internal static StringBuilder GetRawContentHeader(HttpResponseMessage response)
             return raw;
         }
 
-        internal static bool IsJson(string contentType)
+        internal static bool IsJson([NotNullWhen(true)] string? contentType)
         {
             if (string.IsNullOrEmpty(contentType))
             {
@@ -80,7 +83,7 @@ internal static bool IsJson(string contentType)
             return isJson;
         }
 
-        internal static bool IsText(string contentType)
+        internal static bool IsText([NotNullWhen(true)] string? contentType)
         {
             if (string.IsNullOrEmpty(contentType))
             {
@@ -96,19 +99,18 @@ internal static bool IsText(string contentType)
             if (Platform.IsWindows && !isText)
             {
                 // Media types registered with Windows as having a perceived type of text, are text
-                using (RegistryKey contentTypeKey = Registry.ClassesRoot.OpenSubKey(@"MIME\Database\Content Type\" + contentType))
+                using (RegistryKey? contentTypeKey = Registry.ClassesRoot.OpenSubKey(@"MIME\Database\Content Type\" + contentType))
                 {
                     if (contentTypeKey != null)
                     {
-                        string extension = contentTypeKey.GetValue("Extension") as string;
-                        if (extension != null)
+                        if (contentTypeKey.GetValue("Extension") is string extension)
                         {
-                            using (RegistryKey extensionKey = Registry.ClassesRoot.OpenSubKey(extension))
+                            using (RegistryKey? extensionKey = Registry.ClassesRoot.OpenSubKey(extension))
                             {
                                 if (extensionKey != null)
                                 {
-                                    string perceivedType = extensionKey.GetValue("PerceivedType") as string;
-                                    isText = (perceivedType == "text");
+                                    string? perceivedType = extensionKey.GetValue("PerceivedType") as string;
+                                    isText = perceivedType == "text";
                                 }
                             }
                         }
@@ -119,7 +121,7 @@ internal static bool IsText(string contentType)
             return isText;
         }
 
-        internal static bool IsXml(string contentType)
+        internal static bool IsXml([NotNullWhen(true)] string? contentType)
         {
             if (string.IsNullOrEmpty(contentType))
             {

diff --git a/...hell.Commands.Utility/commands/utility/WebCmdlet/Common/InvokeRestMethodCommand.Common.cs b/...hell.Commands.Utility/commands/utility/WebCmdlet/Common/InvokeRestMethodCommand.Common.cs
@@ -1,7 +1,10 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
 
+#nullable enable
+
 using System;
+using System.Diagnostics.CodeAnalysis;
 using System.IO;
 using System.Management.Automation;
 using System.Net.Http;
@@ -56,13 +59,13 @@ public int MaximumFollowRelLink
         /// </summary>
         [Parameter]
         [Alias("RHV")]
-        public string ResponseHeadersVariable { get; set; }
+        public string? ResponseHeadersVariable { get; set; }
 
         /// <summary>
         /// Gets or sets the variable name to use for storing the status code from the response.
         /// </summary>
         [Parameter]
-        public string StatusCodeVariable { get; set; }
+        public string? StatusCodeVariable { get; set; }
 
         #endregion Parameters
 
@@ -95,12 +98,12 @@ internal override void ProcessResponse(HttpResponseMessage response)
                     RestReturnType returnType = CheckReturnType(response);
 
                     // Try to get the response encoding from the ContentType header.
-                    string charSet = WebResponseHelper.GetCharacterSet(response);
+                    string? characterSet = WebResponseHelper.GetCharacterSet(response);
 
-                    string str = StreamHelper.DecodeStream(responseStream, charSet, out Encoding encoding, _cancelToken.Token);
+                    string str = StreamHelper.DecodeStream(responseStream, characterSet, out Encoding encoding, _cancelToken.Token);
 
-                    object obj = null;
-                    Exception ex = null;
+                    object? obj = null;
+                    Exception? ex = null;
 
                     string encodingVerboseName;
                     try
@@ -167,7 +170,7 @@ private static RestReturnType CheckReturnType(HttpResponseMessage response)
             ArgumentNullException.ThrowIfNull(response);
 
             RestReturnType rt = RestReturnType.Detect;
-            string contentType = ContentHelper.GetContentType(response);
+            string? contentType = ContentHelper.GetContentType(response);
             if (string.IsNullOrEmpty(contentType))
             {
                 rt = RestReturnType.Detect;
@@ -223,7 +226,7 @@ private bool TryProcessFeedStream(Stream responseStream)
                            )
                         {
                             // This one will do reader.Read() internally
-                            XmlNode result = workingDocument.ReadNode(reader);
+                            XmlNode? result = workingDocument.ReadNode(reader);
                             WriteObject(result);
                         }
                         else
@@ -262,7 +265,7 @@ private static XmlReaderSettings GetSecureXmlReaderSettings()
             return xrs;
         }
 
-        private static bool TryConvertToXml(string xml, out object doc, ref Exception exRef)
+        private static bool TryConvertToXml(string xml, [NotNullWhen(true)] out object? doc, ref Exception? exRef)
         {
             try
             {
@@ -284,13 +287,12 @@ private static bool TryConvertToXml(string xml, out object doc, ref Exception ex
             return doc != null;
         }
 
-        private static bool TryConvertToJson(string json, out object obj, ref Exception exRef)
+        private static bool TryConvertToJson(string json, [NotNullWhen(true)] out object? obj, ref Exception? exRef)
         {
             bool converted = false;
             try
             {
-                ErrorRecord error;
-                obj = JsonObject.ConvertFromJson(json, out error);
+                obj = JsonObject.ConvertFromJson(json, out ErrorRecord error);
 
                 if (obj == null)
                 {
@@ -340,7 +342,7 @@ public enum RestReturnType
             /// <summary>
             /// Json return type.
             /// </summary>
-            [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Naming", "CA1704:IdentifiersShouldBeSpelledCorrectly")]
+            [SuppressMessage("Microsoft.Naming", "CA1704:IdentifiersShouldBeSpelledCorrectly")]
             Json,
 
             /// <summary>

diff --git a/...PowerShell.Commands.Utility/commands/utility/WebCmdlet/Common/WebResponseObject.Common.cs b/...PowerShell.Commands.Utility/commands/utility/WebCmdlet/Common/WebResponseObject.Common.cs
@@ -1,6 +1,8 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
 
+#nullable enable
+
 using System;
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
@@ -26,22 +28,22 @@ public class WebResponseObject
         /// <summary>
         /// Gets or protected sets the response body content.
         /// </summary>
-        public byte[] Content { get; protected set; }
+        public byte[]? Content { get; protected set; }
 
         /// <summary>
         /// Gets the Headers property.
         /// </summary>
         public Dictionary<string, IEnumerable<string>> Headers => _headers ??= WebResponseHelper.GetHeadersDictionary(BaseResponse);
 
-        private Dictionary<string, IEnumerable<string>> _headers = null;
+        private Dictionary<string, IEnumerable<string>>? _headers;
 
         /// <summary>
         /// Gets or protected sets the full response content.
         /// </summary>
         /// <value>
         /// Full response content, including the HTTP status line, headers, and body.
         /// </value>
-        public string RawContent { get; protected set; }
+        public string? RawContent { get; protected set; }
 
         /// <summary>
         /// Gets the length (in bytes) of <see cref="RawContentStream"/>.
@@ -56,7 +58,7 @@ public class WebResponseObject
         /// <summary>
         /// Gets the RelationLink property.
         /// </summary>
-        public Dictionary<string, string> RelationLink { get; internal set; }
+        public Dictionary<string, string>? RelationLink { get; internal set; }
 
         /// <summary>
         /// Gets the response status code.
@@ -77,8 +79,7 @@ public class WebResponseObject
         /// </summary>
         /// <param name="response">The Http response.</param>
         /// <param name="cancellationToken">The cancellation token.</param>
-        public WebResponseObject(HttpResponseMessage response, CancellationToken cancellationToken) : this(response, null, cancellationToken)
-        { }
+        public WebResponseObject(HttpResponseMessage response, CancellationToken cancellationToken) : this(response, null, cancellationToken) { }
 
         /// <summary>
         /// Initializes a new instance of the <see cref="WebResponseObject"/> class
@@ -87,7 +88,7 @@ public WebResponseObject(HttpResponseMessage response, CancellationToken cancell
         /// <param name="response">Http response.</param>
         /// <param name="contentStream">The http content stream.</param>
         /// <param name="cancellationToken">The cancellation token.</param>
-        public WebResponseObject(HttpResponseMessage response, Stream contentStream, CancellationToken cancellationToken)
+        public WebResponseObject(HttpResponseMessage response, Stream? contentStream, CancellationToken cancellationToken)
         {
             SetResponse(response, contentStream, cancellationToken);
             InitializeContent();
@@ -111,9 +112,9 @@ private void InitializeRawContent(HttpResponseMessage baseResponse)
             StringBuilder raw = ContentHelper.GetRawContentHeader(baseResponse);
 
             // Use ASCII encoding for the RawContent visual view of the content.
-            if (Content.Length > 0)
+            if (Content?.Length > 0)
             {
-                raw.Append(this.ToString());
+                raw.Append(ToString());
             }
 
             RawContent = raw.ToString();
@@ -125,26 +126,23 @@ private static bool IsPrintable(char c) => char.IsLetterOrDigit(c)
                                                 || char.IsSymbol(c)
                                                 || char.IsWhiteSpace(c);
 
-        private void SetResponse(HttpResponseMessage response, Stream contentStream, CancellationToken cancellationToken)
+        [MemberNotNull(nameof(RawContentStream))]
+        [MemberNotNull(nameof(BaseResponse))]
+        private void SetResponse(HttpResponseMessage response, Stream? contentStream, CancellationToken cancellationToken)
         {
             ArgumentNullException.ThrowIfNull(response);
 
             BaseResponse = response;
 
-            MemoryStream ms = contentStream as MemoryStream;
-            if (ms is not null)
+            if (contentStream is MemoryStream ms)
             {
                 RawContentStream = ms;
             }
             else
             {
-                Stream st = contentStream;
-                if (contentStream is null)
-                {
-                    st = StreamHelper.GetResponseStream(response, cancellationToken);
-                }
+                Stream st = contentStream ?? StreamHelper.GetResponseStream(response, cancellationToken);
 
-                long contentLength = response.Content.Headers.ContentLength.Value;
+                long contentLength = response.Content.Headers.ContentLength.GetValueOrDefault();
                 if (contentLength <= 0)
                 {
                     contentLength = StreamHelper.DefaultReadBuffer;
@@ -164,7 +162,12 @@ private void SetResponse(HttpResponseMessage response, Stream contentStream, Can
         /// <returns>The string representation of this web response.</returns>
         public sealed override string ToString()
         {
-            char[] stringContent = System.Text.Encoding.ASCII.GetChars(Content);
+            if (Content is null)
+            {
+                return string.Empty;
+            }
+
+            char[] stringContent = Encoding.ASCII.GetChars(Content);
             for (int counter = 0; counter < stringContent.Length; counter++)
             {
                 if (!IsPrintable(stringContent[counter]))

diff --git a/...ft.PowerShell.Commands.Utility/commands/utility/WebCmdlet/CoreCLR/HttpKnownHeaderNames.cs b/...ft.PowerShell.Commands.Utility/commands/utility/WebCmdlet/CoreCLR/HttpKnownHeaderNames.cs
@@ -1,6 +1,8 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
 
+#nullable enable
+
 using System;
 using System.Collections.Generic;