Improve StringBuilder usage (#44691)

4 files changed, 45 insertions, 38 deletions

diff --git a/src/Mvc/Mvc.Core/src/Infrastructure/ResourceInvoker.Log.cs b/src/Mvc/Mvc.Core/src/Infrastructure/ResourceInvoker.Log.cs
index f34b1e5e53..5e997ba924 100644
--- a/src/Mvc/Mvc.Core/src/Infrastructure/ResourceInvoker.Log.cs
+++ b/src/Mvc/Mvc.Core/src/Infrastructure/ResourceInvoker.Log.cs
@@ -1,7 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
-using System.Linq;
+using System.Globalization;
 using System.Reflection;
 using System.Text;
 using Microsoft.AspNetCore.Mvc.Abstractions;
@@ -21,20 +21,21 @@ internal partial class ResourceInvoker
         {
             if (logger.IsEnabled(LogLevel.Information))
             {
-                var routeKeys = action.RouteValues.Keys.ToArray();
-                var routeValues = action.RouteValues.Values.ToArray();
                 var stringBuilder = new StringBuilder();
                 stringBuilder.Append('{');
-                for (var i = 0; i < routeValues.Length; i++)
+                var index = 0;
+                var count = action.RouteValues.Count;
+                foreach (var (key, value) in action.RouteValues)
                 {
-                    if (i == routeValues.Length - 1)
+                    if (index == count - 1)
                     {
-                        stringBuilder.Append(FormattableString.Invariant($"{routeKeys[i]} = \"{routeValues[i]}\""));
+                        stringBuilder.Append(CultureInfo.InvariantCulture, $"{key} = \"{value}\"");
                     }
                     else
                     {
-                        stringBuilder.Append(FormattableString.Invariant($"{routeKeys[i]} = \"{routeValues[i]}\", "));
+                        stringBuilder.Append(CultureInfo.InvariantCulture, $"{key} = \"{value}\", ");
                     }
+                    index++;
                 }
                 stringBuilder.Append('}');
 
diff --git a/src/Security/Authentication/Facebook/src/FacebookHandler.cs b/src/Security/Authentication/Facebook/src/FacebookHandler.cs
index 0c91dfc664..c2e65e59fc 100644
--- a/src/Security/Authentication/Facebook/src/FacebookHandler.cs
+++ b/src/Security/Authentication/Facebook/src/FacebookHandler.cs
@@ -64,7 +64,7 @@ public class FacebookHandler : OAuthHandler<FacebookOptions>
         var builder = new StringBuilder();
         for (int i = 0; i < hash.Length; i++)
         {
-            builder.Append(hash[i].ToString("x2", CultureInfo.InvariantCulture));
+            builder.Append(CultureInfo.InvariantCulture, $"{hash[i]:x2}");
         }
         return builder.ToString();
     }
diff --git a/src/Security/Authentication/Twitter/src/TwitterHandler.cs b/src/Security/Authentication/Twitter/src/TwitterHandler.cs
index 6c91b2d9f2..00147aa4cc 100644
--- a/src/Security/Authentication/Twitter/src/TwitterHandler.cs
+++ b/src/Security/Authentication/Twitter/src/TwitterHandler.cs
@@ -203,46 +203,48 @@ public partial class TwitterHandler : RemoteAuthenticationHandler<TwitterOptions
             }
         }
 
-        var parameterBuilder = new StringBuilder();
+        var stringBuilder = new StringBuilder();
         foreach (var signaturePart in signatureParts)
         {
-            parameterBuilder.AppendFormat(CultureInfo.InvariantCulture, "{0}={1}&", Uri.EscapeDataString(signaturePart.Key), Uri.EscapeDataString(signaturePart.Value));
+            stringBuilder.AppendFormat(CultureInfo.InvariantCulture, "{0}={1}&", Uri.EscapeDataString(signaturePart.Key), Uri.EscapeDataString(signaturePart.Value));
         }
-        parameterBuilder.Length--;
-        var parameterString = parameterBuilder.ToString();
-
-        var canonicalizedRequestBuilder = new StringBuilder();
-        canonicalizedRequestBuilder.Append(httpMethod.Method);
-        canonicalizedRequestBuilder.Append('&');
-        canonicalizedRequestBuilder.Append(Uri.EscapeDataString(url));
-        canonicalizedRequestBuilder.Append('&');
-        canonicalizedRequestBuilder.Append(Uri.EscapeDataString(parameterString));
-
-        var signature = ComputeSignature(Options.ConsumerSecret!, accessToken?.TokenSecret, canonicalizedRequestBuilder.ToString());
+        stringBuilder.Length--;
+        var parameterString = stringBuilder.ToString();
+        stringBuilder.Clear();
+
+        stringBuilder.Append(httpMethod.Method);
+        stringBuilder.Append('&');
+        stringBuilder.Append(Uri.EscapeDataString(url));
+        stringBuilder.Append('&');
+        stringBuilder.Append(Uri.EscapeDataString(parameterString));
+
+        var signature = ComputeSignature(Options.ConsumerSecret!, accessToken?.TokenSecret, stringBuilder.ToString());
+        stringBuilder.Clear();
         authorizationParts.Add("oauth_signature", signature);
 
         var queryString = "";
         if (queryParameters != null)
         {
-            var queryStringBuilder = new StringBuilder("?");
+            stringBuilder.Append('?');
             foreach (var queryParam in queryParameters)
             {
-                queryStringBuilder.AppendFormat(CultureInfo.InvariantCulture, "{0}={1}&", queryParam.Key, queryParam.Value);
+                stringBuilder.AppendFormat(CultureInfo.InvariantCulture, "{0}={1}&", queryParam.Key, queryParam.Value);
             }
-            queryStringBuilder.Length--;
-            queryString = queryStringBuilder.ToString();
+            stringBuilder.Length--;
+            queryString = stringBuilder.ToString();
+            stringBuilder.Clear();
         }
 
-        var authorizationHeaderBuilder = new StringBuilder();
-        authorizationHeaderBuilder.Append("OAuth ");
+        stringBuilder.Append("OAuth ");
         foreach (var authorizationPart in authorizationParts)
         {
-            authorizationHeaderBuilder.AppendFormat(CultureInfo.InvariantCulture, "{0}=\"{1}\",", authorizationPart.Key, Uri.EscapeDataString(authorizationPart.Value));
+            stringBuilder.AppendFormat(CultureInfo.InvariantCulture, "{0}=\"{1}\",", authorizationPart.Key, Uri.EscapeDataString(authorizationPart.Value));
         }
-        authorizationHeaderBuilder.Length--;
+        stringBuilder.Length--;
 
         var request = new HttpRequestMessage(httpMethod, url + queryString);
-        request.Headers.Add("Authorization", authorizationHeaderBuilder.ToString());
+        request.Headers.Add("Authorization", stringBuilder.ToString());
+        stringBuilder.Clear();
 
         // This header is so that the error response is also JSON - without it the success response is already JSON
         request.Headers.Add("Accept", "application/json");
@@ -380,7 +382,7 @@ public partial class TwitterHandler : RemoteAuthenticationHandler<TwitterOptions
             foreach (var error in errorResponse.Errors)
             {
                 errorMessageStringBuilder.Append(Environment.NewLine);
-                errorMessageStringBuilder.Append(FormattableString.Invariant($"Code: {error.Code}, Message: '{error.Message}'"));
+                errorMessageStringBuilder.Append(CultureInfo.InvariantCulture, $"Code: {error.Code}, Message: '{error.Message}'");
             }
         }
 
diff --git a/src/Servers/Kestrel/Core/src/Middleware/Internal/LoggingStream.cs b/src/Servers/Kestrel/Core/src/Middleware/Internal/LoggingStream.cs
index af3164df75..924398acbc 100644
--- a/src/Servers/Kestrel/Core/src/Middleware/Internal/LoggingStream.cs
+++ b/src/Servers/Kestrel/Core/src/Middleware/Internal/LoggingStream.cs
@@ -165,22 +165,25 @@ internal sealed class LoggingStream : Stream
             builder.AppendLine();
         }
 
-        var charBuilder = new StringBuilder();
+        // A maximum of 2 8 byte segments are written at once with a space between them, meaning 17 characters can be written
+        // ........ ........
+        Span<char> charBuilder = stackalloc char[17];
+        var charBuilderIndex = 0;
 
         // Write the hex
         for (int i = 0; i < buffer.Length; i++)
         {
-            builder.Append(buffer[i].ToString("X2", CultureInfo.InvariantCulture));
+            builder.Append(CultureInfo.InvariantCulture, $"{buffer[i]:X2}");
             builder.Append(' ');
 
             var bufferChar = (char)buffer[i];
             if (char.IsControl(bufferChar))
             {
-                charBuilder.Append('.');
+                charBuilder[charBuilderIndex++] = '.';
             }
             else
             {
-                charBuilder.Append(bufferChar);
+                charBuilder[charBuilderIndex++] = bufferChar;
             }
 
             if ((i + 1) % 16 == 0)
@@ -192,11 +195,12 @@ internal sealed class LoggingStream : Stream
                     builder.AppendLine();
                 }
                 charBuilder.Clear();
+                charBuilderIndex = 0;
             }
             else if ((i + 1) % 8 == 0)
             {
                 builder.Append(' ');
-                charBuilder.Append(' ');
+                charBuilder[charBuilderIndex++] = ' ';
             }
         }
 
@@ -213,8 +217,8 @@ internal sealed class LoggingStream : Stream
                 padLength++;
             }
 
-            builder.Append(new string(' ', padLength));
-            builder.Append(charBuilder);
+            builder.Append(' ', padLength);
+            builder.Append(charBuilder.Slice(0, charBuilderIndex));
         }
 
         _logger.LogDebug(builder.ToString());