Improvements in EmbedIO.Net.Internal namespace; also, component collections are back.

src/EmbedIO/EmbedIO.csproj

@@ -38,11 +38,15 @@
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers</IncludeAssets>
     </PackageReference>
+    <PackageReference Include="Nullable" Version="1.2.0">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
     <PackageReference Include="StyleCop.Analyzers" Version="1.1.118">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers</IncludeAssets>
     </PackageReference>
-    <PackageReference Include="Unosquare.Swan.Lite" Version="2.6.1" />
+    <PackageReference Include="Unosquare.Swan.Lite" Version="2.6.2" />
   </ItemGroup>
 
 </Project>

src/EmbedIO/Files/FileModule.cs

@@ -505,12 +505,12 @@ private async Task HandleResource(IHttpContext context, MappedResourceInfo info,
             var partialUpperBound = contentLength - 1;
             var isPartial = compressionMethod == CompressionMethod.None
                          && context.Request.IsRangeRequest(contentLength, entityTag, info.LastModifiedUtc, out partialStart, out partialUpperBound);
-            var partialLength = contentLength;
+            var responseContentLength = contentLength;
 
             if (isPartial)
             {
                 // Prepare a "206 Partial Content" response.
-                partialLength = partialUpperBound - partialStart + 1;
+                responseContentLength = partialUpperBound - partialStart + 1;
                 context.Response.StatusCode = (int)HttpStatusCode.PartialContent;
                 PreparePositiveResponse(context.Response, info, contentType, entityTag, setCompressionInResponse);
                 context.Response.Headers.Set(HttpHeaderNames.ContentRange, $"bytes {partialStart}-{partialUpperBound}/{contentLength}");
@@ -548,18 +548,10 @@ await source.CopyToAsync(compressor, WebServer.StreamCopyBufferSize, context.Can
             // Transfer cached content if present.
             if (content != null)
             {
-                if (isPartial)
-                {
-                    context.Response.ContentLength64 = partialLength;
-                    await context.Response.OutputStream.WriteAsync(content, (int)partialStart, (int)partialLength, context.CancellationToken)
-                        .ConfigureAwait(false);
-                }
-                else
-                {
-                    context.Response.ContentLength64 = content.Length;
-                    await context.Response.OutputStream.WriteAsync(content, 0, content.Length, context.CancellationToken)
-                        .ConfigureAwait(false);
-                }
+                context.Response.ContentLength64 = responseContentLength;
+                var offset = isPartial ? (int) partialStart : 0;
+                await context.Response.OutputStream.WriteAsync(content, offset, (int)responseContentLength, context.CancellationToken)
+                    .ConfigureAwait(false);
 
                 return;
             }
@@ -588,7 +580,7 @@ await context.Response.OutputStream.WriteAsync(content, 0, content.Length, conte
                         }
                     }
 
-                    var transferSize = partialLength;
+                    var transferSize = responseContentLength;
                     while (transferSize >= WebServer.StreamCopyBufferSize)
                     {
                         var read = await source.ReadAsync(buffer, 0, WebServer.StreamCopyBufferSize, context.CancellationToken)

src/EmbedIO/Files/Internal/FileCacheItem.cs

@@ -5,7 +5,7 @@ namespace EmbedIO.Files.Internal
 {
     internal sealed class FileCacheItem
     {
-#pragma warning disable SA1401 // Field should be private - performance is a strongest concern here.
+#pragma warning disable SA1401 // Field should be private - performance is a stronger concern here.
         // These fields create a sort of linked list of items
         // inside the cache's dictionary.
         // Their purpose is to keep track of items
@@ -21,6 +21,8 @@ internal sealed class FileCacheItem
         // Size of a WeakReference<T> in bytes
         private static readonly long SizeOfWeakReference = Environment.Is64BitProcess ? 16 : 32;
 
+        private readonly object _syncRoot = new object();
+
         // Educated guess about the size of an Item in memory (see comments on constructor).
         // 3 * SizeOfPointer + total size of fields, rounded up to a multiple of 16.
         //
@@ -122,7 +124,7 @@ internal FileCacheItem(FileCache.Section section, DateTime lastModifiedUtc, long
             // This is the bare minimum locking we need
             // to ensure we don't mess sizes up.
             byte[]? oldContent;
-            lock (this)
+            lock (_syncRoot)
             {
                 switch (compressionMethod)
                 {

src/EmbedIO/HttpContextExtensions-Redirect.cs

@@ -0,0 +1,33 @@
+using System;
+using System.Net;
+using EmbedIO.Utilities;
+
+namespace EmbedIO
+{
+    partial class HttpContextExtensions
+    {
+        /// <summary>
+        /// Sets a redirection status code and adds a <c>Location</c> header to the response.
+        /// </summary>
+        /// <param name="this">The <see cref="IHttpContext"/> interface on which this method is called.</param>
+        /// <param name="location">The URL to which the user agent should be redirected.</param>
+        /// <param name="statusCode">The status code to set on the response.</param>
+        /// <exception cref="NullReferenceException"><paramref name="this"/> is <see langword="null"/>.</exception>
+        /// <exception cref="ArgumentNullException"><paramref name="location"/> is <see langword="null"/>.</exception>
+        /// <exception cref="ArgumentException">
+        /// <para><paramref name="location"/> is not a valid relative or absolute URL.<see langword="null"/>.</para>
+        /// <para>- or -</para>
+        /// <para><paramref name="statusCode"/> is not a redirection (3xx) status code.</para>
+        /// </exception>
+        public static void Redirect(this IHttpContext @this, string location, int statusCode = (int)HttpStatusCode.Found)
+        {
+            location = Validate.Url(nameof(location), location, @this.Request.Url);
+
+            if (statusCode < 300 || statusCode > 399)
+                throw new ArgumentException("Redirect status code is not valid.", nameof(statusCode));
+
+            @this.Response.SetEmptyResponse(statusCode);
+            @this.Response.Headers[HttpHeaderNames.Location] = location;
+        }
+    }
+}

src/EmbedIO/HttpContextExtensions-Responses.cs

@@ -12,30 +12,6 @@ partial class HttpContextExtensions
         private const string StandardHtmlHeaderFormat = "<html><head><meta charset=\"{2}\"><title>{0} - {1}</title></head><body><h1>{0} - {1}</h1>";
         private const string StandardHtmlFooter = "</body></html>";
 
-        /// <summary>
-        /// Sets a redirection status code and adds a <c>Location</c> header to the response.
-        /// </summary>
-        /// <param name="this">The <see cref="IHttpContext"/> interface on which this method is called.</param>
-        /// <param name="location">The URL to which the user agent should be redirected.</param>
-        /// <param name="statusCode">The status code to set on the response.</param>
-        /// <exception cref="NullReferenceException"><paramref name="this"/> is <see langword="null"/>.</exception>
-        /// <exception cref="ArgumentNullException"><paramref name="location"/> is <see langword="null"/>.</exception>
-        /// <exception cref="ArgumentException">
-        /// <para><paramref name="location"/> is not a valid relative or absolute URL.<see langword="null"/>.</para>
-        /// <para>- or -</para>
-        /// <para><paramref name="statusCode"/> is not a redirection (3xx) status code.</para>
-        /// </exception>
-        public static void Redirect(this IHttpContext @this, string location, int statusCode = (int)HttpStatusCode.Found)
-        {
-            location = Validate.Url(nameof(location), location, @this.Request.Url);
-
-            if (statusCode < 300 || statusCode > 399)
-                throw new ArgumentException("Redirect status code is not valid.", nameof(statusCode));
-
-            @this.Response.SetEmptyResponse(statusCode);
-            @this.Response.Headers[HttpHeaderNames.Location] = location;
-        }
-
         /// <summary>
         /// Asynchronously sends a string as response.
         /// </summary>

src/EmbedIO/HttpResponseExtensions.cs

@@ -36,7 +36,7 @@ public static void SetEmptyResponse(this IHttpResponse @this, int statusCode)
 
             @this.StatusCode = statusCode;
             @this.StatusDescription = statusDescription;
-            @this.ContentType = string.Empty;
+            @this.ContentType = MimeType.Default;
             @this.ContentEncoding = null;
         }
     }

src/EmbedIO/ICookieCollection.cs

@@ -20,7 +20,7 @@ public interface ICookieCollection : IEnumerable<Cookie>, ICollection
         /// </value>
         /// <param name="name">The name.</param>
         /// <returns>The cookie matching the specified name.</returns>
-        Cookie this[string name] { get; }
+        Cookie? this[string name] { get; }
 
         /// <summary>
         /// Determines whether this <see cref="ICookieCollection"/> contains the specified <see cref="Cookie"/>.

src/EmbedIO/IHttpMessage.cs

@@ -23,4 +23,4 @@ public interface IHttpMessage
         /// </value>
         Version ProtocolVersion { get; }
     }
-}
+}

src/EmbedIO/IWebModuleContainer.cs

@@ -1,5 +1,5 @@
 using System.Collections.Concurrent;
-using Swan.Collections;
+using EmbedIO.Utilities;
 
 namespace EmbedIO
 {

src/EmbedIO/Internal/DummyWebModuleContainer.cs

@@ -1,7 +1,7 @@
 using System.Collections.Concurrent;
 using System.Runtime.CompilerServices;
 using Swan;
-using Swan.Collections;
+using EmbedIO.Utilities;
 
 namespace EmbedIO.Internal
 {

src/EmbedIO/Internal/WebModuleCollection.cs

@@ -1,7 +1,7 @@
 using System;
 using System.Threading;
 using System.Threading.Tasks;
-using Swan.Collections;
+using EmbedIO.Utilities;
 using Swan.Logging;
 
 namespace EmbedIO.Internal

src/EmbedIO/ModuleGroup.cs

@@ -4,7 +4,7 @@
 using System.Threading;
 using System.Threading.Tasks;
 using EmbedIO.Internal;
-using Swan.Collections;
+using EmbedIO.Utilities;
 
 namespace EmbedIO
 {

src/EmbedIO/Net/Internal/HttpListenerRequest.cs

@@ -111,7 +111,7 @@ public Encoding ContentEncoding
         public bool IsAuthenticated => false;
 
         /// <inheritdoc />
-        public bool IsLocal => LocalEndPoint?.Address?.Equals(RemoteEndPoint?.Address) ?? true;
+        public bool IsLocal => LocalEndPoint.Address?.Equals(RemoteEndPoint.Address) ?? true;
 
         /// <inheritdoc />
         public bool IsSecureConnection => _context.Connection.IsSecure;
@@ -124,28 +124,12 @@ public bool KeepAlive
                 if (_kaSet)
                     return _keepAlive;
 
-                _kaSet = true;
-
-                // 1. Connection header
-                // 2. Protocol (1.1 == keep-alive by default)
-                // 3. Keep-Alive header
-                var cnc = Headers[HttpHeaderNames.Connection];
-                if (!string.IsNullOrEmpty(cnc))
-                {
-                    _keepAlive = string.Compare(cnc, "keep-alive", StringComparison.OrdinalIgnoreCase) == 0;
-                }
-                else if (ProtocolVersion == HttpVersion.Version11)
-                {
-                    _keepAlive = true;
-                }
-                else
-                {
-                    cnc = Headers[HttpHeaderNames.KeepAlive];
-
-                    if (!string.IsNullOrEmpty(cnc))
-                        _keepAlive = string.Compare(cnc, "closed", StringComparison.OrdinalIgnoreCase) != 0;
-                }
+                var cnc = Headers.GetValues(HttpHeaderNames.Connection);
+                _keepAlive = ProtocolVersion < HttpVersion.Version11
+                    ? cnc != null && cnc.Length == 1 && string.Compare(cnc[0], "keep-alive", StringComparison.OrdinalIgnoreCase) == 0
+                    : cnc == null || cnc.All(s => string.Compare(s, "close", StringComparison.OrdinalIgnoreCase) != 0);
 
+                _kaSet = true;
                 return _keepAlive;
             }
         }