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authorcrobibero <cody@robibe.ro>2020-09-03 09:29:07 -0600
committercrobibero <cody@robibe.ro>2020-09-03 09:29:07 -0600
commit5ad81f7fe6e37a7e513c3b06c5bed7a229704bbc (patch)
tree807660528f6117b151288645119af4227286433b /Emby.Server.Implementations/HttpServer/HttpResultFactory.cs
parentb216b91e219541b805c420ebd64cdc13d3023be4 (diff)
parent3711a1978e8a400aa28dd75ce8ffb08ac43106e1 (diff)
Merge remote-tracking branch 'upstream/master' into 3.1.7
Diffstat (limited to 'Emby.Server.Implementations/HttpServer/HttpResultFactory.cs')
-rw-r--r--Emby.Server.Implementations/HttpServer/HttpResultFactory.cs721
1 files changed, 0 insertions, 721 deletions
diff --git a/Emby.Server.Implementations/HttpServer/HttpResultFactory.cs b/Emby.Server.Implementations/HttpServer/HttpResultFactory.cs
deleted file mode 100644
index 688216373..000000000
--- a/Emby.Server.Implementations/HttpServer/HttpResultFactory.cs
+++ /dev/null
@@ -1,721 +0,0 @@
-#pragma warning disable CS1591
-
-using System;
-using System.Collections.Generic;
-using System.Globalization;
-using System.IO;
-using System.IO.Compression;
-using System.Net;
-using System.Runtime.Serialization;
-using System.Text;
-using System.Threading.Tasks;
-using System.Xml;
-using Emby.Server.Implementations.Services;
-using MediaBrowser.Controller.Net;
-using MediaBrowser.Model.IO;
-using MediaBrowser.Model.Serialization;
-using MediaBrowser.Model.Services;
-using Microsoft.Extensions.Logging;
-using Microsoft.Extensions.Primitives;
-using Microsoft.Net.Http.Headers;
-using IRequest = MediaBrowser.Model.Services.IRequest;
-using MimeTypes = MediaBrowser.Model.Net.MimeTypes;
-
-namespace Emby.Server.Implementations.HttpServer
-{
- /// <summary>
- /// Class HttpResultFactory.
- /// </summary>
- public class HttpResultFactory : IHttpResultFactory
- {
- // Last-Modified and If-Modified-Since must follow strict date format,
- // see https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/If-Modified-Since
- private const string HttpDateFormat = "ddd, dd MMM yyyy HH:mm:ss \"GMT\"";
- // We specifically use en-US culture because both day of week and month names require it
- private static readonly CultureInfo _enUSculture = new CultureInfo("en-US", false);
-
- /// <summary>
- /// The logger.
- /// </summary>
- private readonly ILogger<HttpResultFactory> _logger;
- private readonly IFileSystem _fileSystem;
- private readonly IJsonSerializer _jsonSerializer;
- private readonly IStreamHelper _streamHelper;
-
- /// <summary>
- /// Initializes a new instance of the <see cref="HttpResultFactory" /> class.
- /// </summary>
- public HttpResultFactory(ILoggerFactory loggerfactory, IFileSystem fileSystem, IJsonSerializer jsonSerializer, IStreamHelper streamHelper)
- {
- _fileSystem = fileSystem;
- _jsonSerializer = jsonSerializer;
- _streamHelper = streamHelper;
- _logger = loggerfactory.CreateLogger<HttpResultFactory>();
- }
-
- /// <summary>
- /// Gets the result.
- /// </summary>
- /// <param name="requestContext">The request context.</param>
- /// <param name="content">The content.</param>
- /// <param name="contentType">Type of the content.</param>
- /// <param name="responseHeaders">The response headers.</param>
- /// <returns>System.Object.</returns>
- public object GetResult(IRequest requestContext, byte[] content, string contentType, IDictionary<string, string> responseHeaders = null)
- {
- return GetHttpResult(requestContext, content, contentType, true, responseHeaders);
- }
-
- public object GetResult(string content, string contentType, IDictionary<string, string> responseHeaders = null)
- {
- return GetHttpResult(null, content, contentType, true, responseHeaders);
- }
-
- public object GetResult(IRequest requestContext, Stream content, string contentType, IDictionary<string, string> responseHeaders = null)
- {
- return GetHttpResult(requestContext, content, contentType, true, responseHeaders);
- }
-
- public object GetResult(IRequest requestContext, string content, string contentType, IDictionary<string, string> responseHeaders = null)
- {
- return GetHttpResult(requestContext, content, contentType, true, responseHeaders);
- }
-
- public object GetRedirectResult(string url)
- {
- var responseHeaders = new Dictionary<string, string>();
- responseHeaders[HeaderNames.Location] = url;
-
- var result = new HttpResult(Array.Empty<byte>(), "text/plain", HttpStatusCode.Redirect);
-
- AddResponseHeaders(result, responseHeaders);
-
- return result;
- }
-
- /// <summary>
- /// Gets the HTTP result.
- /// </summary>
- private IHasHeaders GetHttpResult(IRequest requestContext, Stream content, string contentType, bool addCachePrevention, IDictionary<string, string> responseHeaders = null)
- {
- var result = new StreamWriter(content, contentType);
-
- if (responseHeaders == null)
- {
- responseHeaders = new Dictionary<string, string>();
- }
-
- if (addCachePrevention && !responseHeaders.TryGetValue(HeaderNames.Expires, out _))
- {
- responseHeaders[HeaderNames.Expires] = "0";
- }
-
- AddResponseHeaders(result, responseHeaders);
-
- return result;
- }
-
- /// <summary>
- /// Gets the HTTP result.
- /// </summary>
- private IHasHeaders GetHttpResult(IRequest requestContext, byte[] content, string contentType, bool addCachePrevention, IDictionary<string, string> responseHeaders = null)
- {
- string compressionType = null;
- bool isHeadRequest = false;
-
- if (requestContext != null)
- {
- compressionType = GetCompressionType(requestContext, content, contentType);
- isHeadRequest = string.Equals(requestContext.Verb, "head", StringComparison.OrdinalIgnoreCase);
- }
-
- IHasHeaders result;
- if (string.IsNullOrEmpty(compressionType))
- {
- var contentLength = content.Length;
-
- if (isHeadRequest)
- {
- content = Array.Empty<byte>();
- }
-
- result = new StreamWriter(content, contentType, contentLength);
- }
- else
- {
- result = GetCompressedResult(content, compressionType, responseHeaders, isHeadRequest, contentType);
- }
-
- if (responseHeaders == null)
- {
- responseHeaders = new Dictionary<string, string>();
- }
-
- if (addCachePrevention && !responseHeaders.TryGetValue(HeaderNames.Expires, out string _))
- {
- responseHeaders[HeaderNames.Expires] = "0";
- }
-
- AddResponseHeaders(result, responseHeaders);
-
- return result;
- }
-
- /// <summary>
- /// Gets the HTTP result.
- /// </summary>
- private IHasHeaders GetHttpResult(IRequest requestContext, string content, string contentType, bool addCachePrevention, IDictionary<string, string> responseHeaders = null)
- {
- IHasHeaders result;
-
- var bytes = Encoding.UTF8.GetBytes(content);
-
- var compressionType = requestContext == null ? null : GetCompressionType(requestContext, bytes, contentType);
-
- var isHeadRequest = requestContext == null ? false : string.Equals(requestContext.Verb, "head", StringComparison.OrdinalIgnoreCase);
-
- if (string.IsNullOrEmpty(compressionType))
- {
- var contentLength = bytes.Length;
-
- if (isHeadRequest)
- {
- bytes = Array.Empty<byte>();
- }
-
- result = new StreamWriter(bytes, contentType, contentLength);
- }
- else
- {
- result = GetCompressedResult(bytes, compressionType, responseHeaders, isHeadRequest, contentType);
- }
-
- if (responseHeaders == null)
- {
- responseHeaders = new Dictionary<string, string>();
- }
-
- if (addCachePrevention && !responseHeaders.TryGetValue(HeaderNames.Expires, out string _))
- {
- responseHeaders[HeaderNames.Expires] = "0";
- }
-
- AddResponseHeaders(result, responseHeaders);
-
- return result;
- }
-
- /// <summary>
- /// Gets the optimized result.
- /// </summary>
- /// <typeparam name="T"></typeparam>
- public object GetResult<T>(IRequest requestContext, T result, IDictionary<string, string> responseHeaders = null)
- where T : class
- {
- if (result == null)
- {
- throw new ArgumentNullException(nameof(result));
- }
-
- if (responseHeaders == null)
- {
- responseHeaders = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
- }
-
- responseHeaders[HeaderNames.Expires] = "0";
-
- return ToOptimizedResultInternal(requestContext, result, responseHeaders);
- }
-
- private string GetCompressionType(IRequest request, byte[] content, string responseContentType)
- {
- if (responseContentType == null)
- {
- return null;
- }
-
- // Per apple docs, hls manifests must be compressed
- if (!responseContentType.StartsWith("text/", StringComparison.OrdinalIgnoreCase) &&
- responseContentType.IndexOf("json", StringComparison.OrdinalIgnoreCase) == -1 &&
- responseContentType.IndexOf("javascript", StringComparison.OrdinalIgnoreCase) == -1 &&
- responseContentType.IndexOf("xml", StringComparison.OrdinalIgnoreCase) == -1 &&
- responseContentType.IndexOf("application/x-mpegURL", StringComparison.OrdinalIgnoreCase) == -1)
- {
- return null;
- }
-
- if (content.Length < 1024)
- {
- return null;
- }
-
- return GetCompressionType(request);
- }
-
- private static string GetCompressionType(IRequest request)
- {
- var acceptEncoding = request.Headers[HeaderNames.AcceptEncoding].ToString();
-
- if (!string.IsNullOrEmpty(acceptEncoding))
- {
- // if (_brotliCompressor != null && acceptEncoding.IndexOf("br", StringComparison.OrdinalIgnoreCase) != -1)
- // return "br";
-
- if (acceptEncoding.Contains("deflate", StringComparison.OrdinalIgnoreCase))
- {
- return "deflate";
- }
-
- if (acceptEncoding.Contains("gzip", StringComparison.OrdinalIgnoreCase))
- {
- return "gzip";
- }
- }
-
- return null;
- }
-
- /// <summary>
- /// Returns the optimized result for the IRequestContext.
- /// Does not use or store results in any cache.
- /// </summary>
- /// <param name="request"></param>
- /// <param name="dto"></param>
- /// <returns></returns>
- public object ToOptimizedResult<T>(IRequest request, T dto)
- {
- return ToOptimizedResultInternal(request, dto);
- }
-
- private object ToOptimizedResultInternal<T>(IRequest request, T dto, IDictionary<string, string> responseHeaders = null)
- {
- // TODO: @bond use Span and .Equals
- var contentType = request.ResponseContentType?.Split(';')[0].Trim().ToLowerInvariant();
-
- switch (contentType)
- {
- case "application/xml":
- case "text/xml":
- case "text/xml; charset=utf-8": //"text/xml; charset=utf-8" also matches xml
- return GetHttpResult(request, SerializeToXmlString(dto), contentType, false, responseHeaders);
-
- case "application/json":
- case "text/json":
- return GetHttpResult(request, _jsonSerializer.SerializeToString(dto), contentType, false, responseHeaders);
- default:
- break;
- }
-
- var isHeadRequest = string.Equals(request.Verb, "head", StringComparison.OrdinalIgnoreCase);
-
- var ms = new MemoryStream();
- var writerFn = RequestHelper.GetResponseWriter(HttpListenerHost.Instance, contentType);
-
- writerFn(dto, ms);
-
- ms.Position = 0;
-
- if (isHeadRequest)
- {
- using (ms)
- {
- return GetHttpResult(request, Array.Empty<byte>(), contentType, true, responseHeaders);
- }
- }
-
- return GetHttpResult(request, ms, contentType, true, responseHeaders);
- }
-
- private IHasHeaders GetCompressedResult(
- byte[] content,
- string requestedCompressionType,
- IDictionary<string, string> responseHeaders,
- bool isHeadRequest,
- string contentType)
- {
- if (responseHeaders == null)
- {
- responseHeaders = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
- }
-
- content = Compress(content, requestedCompressionType);
- responseHeaders[HeaderNames.ContentEncoding] = requestedCompressionType;
-
- responseHeaders[HeaderNames.Vary] = HeaderNames.AcceptEncoding;
-
- var contentLength = content.Length;
-
- if (isHeadRequest)
- {
- var result = new StreamWriter(Array.Empty<byte>(), contentType, contentLength);
- AddResponseHeaders(result, responseHeaders);
- return result;
- }
- else
- {
- var result = new StreamWriter(content, contentType, contentLength);
- AddResponseHeaders(result, responseHeaders);
- return result;
- }
- }
-
- private byte[] Compress(byte[] bytes, string compressionType)
- {
- if (string.Equals(compressionType, "deflate", StringComparison.OrdinalIgnoreCase))
- {
- return Deflate(bytes);
- }
-
- if (string.Equals(compressionType, "gzip", StringComparison.OrdinalIgnoreCase))
- {
- return GZip(bytes);
- }
-
- throw new NotSupportedException(compressionType);
- }
-
- private static byte[] Deflate(byte[] bytes)
- {
- // In .NET FX incompat-ville, you can't access compressed bytes without closing DeflateStream
- // Which means we must use MemoryStream since you have to use ToArray() on a closed Stream
- using (var ms = new MemoryStream())
- using (var zipStream = new DeflateStream(ms, CompressionMode.Compress))
- {
- zipStream.Write(bytes, 0, bytes.Length);
- zipStream.Dispose();
-
- return ms.ToArray();
- }
- }
-
- private static byte[] GZip(byte[] buffer)
- {
- using (var ms = new MemoryStream())
- using (var zipStream = new GZipStream(ms, CompressionMode.Compress))
- {
- zipStream.Write(buffer, 0, buffer.Length);
- zipStream.Dispose();
-
- return ms.ToArray();
- }
- }
-
- private static string SerializeToXmlString(object from)
- {
- using (var ms = new MemoryStream())
- {
- var xwSettings = new XmlWriterSettings();
- xwSettings.Encoding = new UTF8Encoding(false);
- xwSettings.OmitXmlDeclaration = false;
-
- using (var xw = XmlWriter.Create(ms, xwSettings))
- {
- var serializer = new DataContractSerializer(from.GetType());
- serializer.WriteObject(xw, from);
- xw.Flush();
- ms.Seek(0, SeekOrigin.Begin);
- using (var reader = new StreamReader(ms))
- {
- return reader.ReadToEnd();
- }
- }
- }
- }
-
- /// <summary>
- /// Pres the process optimized result.
- /// </summary>
- private object GetCachedResult(IRequest requestContext, IDictionary<string, string> responseHeaders, StaticResultOptions options)
- {
- bool noCache = requestContext.Headers[HeaderNames.CacheControl].ToString().IndexOf("no-cache", StringComparison.OrdinalIgnoreCase) != -1;
- AddCachingHeaders(responseHeaders, options.CacheDuration, noCache, options.DateLastModified);
-
- if (!noCache)
- {
- if (!DateTime.TryParseExact(requestContext.Headers[HeaderNames.IfModifiedSince], HttpDateFormat, _enUSculture, DateTimeStyles.AssumeUniversal | DateTimeStyles.AdjustToUniversal, out var ifModifiedSinceHeader))
- {
- _logger.LogDebug("Failed to parse If-Modified-Since header date: {0}", requestContext.Headers[HeaderNames.IfModifiedSince]);
- return null;
- }
-
- if (IsNotModified(ifModifiedSinceHeader, options.CacheDuration, options.DateLastModified))
- {
- AddAgeHeader(responseHeaders, options.DateLastModified);
-
- var result = new HttpResult(Array.Empty<byte>(), options.ContentType ?? "text/html", HttpStatusCode.NotModified);
-
- AddResponseHeaders(result, responseHeaders);
-
- return result;
- }
- }
-
- return null;
- }
-
- public Task<object> GetStaticFileResult(IRequest requestContext,
- string path,
- FileShare fileShare = FileShare.Read)
- {
- if (string.IsNullOrEmpty(path))
- {
- throw new ArgumentNullException(nameof(path));
- }
-
- return GetStaticFileResult(requestContext, new StaticFileResultOptions
- {
- Path = path,
- FileShare = fileShare
- });
- }
-
- public Task<object> GetStaticFileResult(IRequest requestContext, StaticFileResultOptions options)
- {
- var path = options.Path;
- var fileShare = options.FileShare;
-
- if (string.IsNullOrEmpty(path))
- {
- throw new ArgumentException("Path can't be empty.", nameof(options));
- }
-
- if (fileShare != FileShare.Read && fileShare != FileShare.ReadWrite)
- {
- throw new ArgumentException("FileShare must be either Read or ReadWrite");
- }
-
- if (string.IsNullOrEmpty(options.ContentType))
- {
- options.ContentType = MimeTypes.GetMimeType(path);
- }
-
- if (!options.DateLastModified.HasValue)
- {
- options.DateLastModified = _fileSystem.GetLastWriteTimeUtc(path);
- }
-
- options.ContentFactory = () => Task.FromResult(GetFileStream(path, fileShare));
-
- options.ResponseHeaders = options.ResponseHeaders ?? new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
-
- return GetStaticResult(requestContext, options);
- }
-
- /// <summary>
- /// Gets the file stream.
- /// </summary>
- /// <param name="path">The path.</param>
- /// <param name="fileShare">The file share.</param>
- /// <returns>Stream.</returns>
- private Stream GetFileStream(string path, FileShare fileShare)
- {
- return new FileStream(path, FileMode.Open, FileAccess.Read, fileShare);
- }
-
- public Task<object> GetStaticResult(IRequest requestContext,
- Guid cacheKey,
- DateTime? lastDateModified,
- TimeSpan? cacheDuration,
- string contentType,
- Func<Task<Stream>> factoryFn,
- IDictionary<string, string> responseHeaders = null,
- bool isHeadRequest = false)
- {
- return GetStaticResult(requestContext, new StaticResultOptions
- {
- CacheDuration = cacheDuration,
- ContentFactory = factoryFn,
- ContentType = contentType,
- DateLastModified = lastDateModified,
- IsHeadRequest = isHeadRequest,
- ResponseHeaders = responseHeaders
- });
- }
-
- public async Task<object> GetStaticResult(IRequest requestContext, StaticResultOptions options)
- {
- options.ResponseHeaders = options.ResponseHeaders ?? new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
-
- var contentType = options.ContentType;
- if (!StringValues.IsNullOrEmpty(requestContext.Headers[HeaderNames.IfModifiedSince]))
- {
- // See if the result is already cached in the browser
- var result = GetCachedResult(requestContext, options.ResponseHeaders, options);
-
- if (result != null)
- {
- return result;
- }
- }
-
- // TODO: We don't really need the option value
- var isHeadRequest = options.IsHeadRequest || string.Equals(requestContext.Verb, "HEAD", StringComparison.OrdinalIgnoreCase);
- var factoryFn = options.ContentFactory;
- var responseHeaders = options.ResponseHeaders;
- AddCachingHeaders(responseHeaders, options.CacheDuration, false, options.DateLastModified);
- AddAgeHeader(responseHeaders, options.DateLastModified);
-
- var rangeHeader = requestContext.Headers[HeaderNames.Range];
-
- if (!isHeadRequest && !string.IsNullOrEmpty(options.Path))
- {
- var hasHeaders = new FileWriter(options.Path, contentType, rangeHeader, _logger, _fileSystem, _streamHelper)
- {
- OnComplete = options.OnComplete,
- OnError = options.OnError,
- FileShare = options.FileShare
- };
-
- AddResponseHeaders(hasHeaders, options.ResponseHeaders);
- return hasHeaders;
- }
-
- var stream = await factoryFn().ConfigureAwait(false);
-
- var totalContentLength = options.ContentLength;
- if (!totalContentLength.HasValue)
- {
- try
- {
- totalContentLength = stream.Length;
- }
- catch (NotSupportedException)
- {
- }
- }
-
- if (!string.IsNullOrWhiteSpace(rangeHeader) && totalContentLength.HasValue)
- {
- var hasHeaders = new RangeRequestWriter(rangeHeader, totalContentLength.Value, stream, contentType, isHeadRequest)
- {
- OnComplete = options.OnComplete
- };
-
- AddResponseHeaders(hasHeaders, options.ResponseHeaders);
- return hasHeaders;
- }
- else
- {
- if (totalContentLength.HasValue)
- {
- responseHeaders["Content-Length"] = totalContentLength.Value.ToString(CultureInfo.InvariantCulture);
- }
-
- if (isHeadRequest)
- {
- using (stream)
- {
- return GetHttpResult(requestContext, Array.Empty<byte>(), contentType, true, responseHeaders);
- }
- }
-
- var hasHeaders = new StreamWriter(stream, contentType)
- {
- OnComplete = options.OnComplete,
- OnError = options.OnError
- };
-
- AddResponseHeaders(hasHeaders, options.ResponseHeaders);
- return hasHeaders;
- }
- }
-
- /// <summary>
- /// Adds the caching responseHeaders.
- /// </summary>
- private void AddCachingHeaders(
- IDictionary<string, string> responseHeaders,
- TimeSpan? cacheDuration,
- bool noCache,
- DateTime? lastModifiedDate)
- {
- if (noCache)
- {
- responseHeaders[HeaderNames.CacheControl] = "no-cache, no-store, must-revalidate";
- responseHeaders[HeaderNames.Pragma] = "no-cache, no-store, must-revalidate";
- return;
- }
-
- if (cacheDuration.HasValue)
- {
- responseHeaders[HeaderNames.CacheControl] = "public, max-age=" + cacheDuration.Value.TotalSeconds;
- }
- else
- {
- responseHeaders[HeaderNames.CacheControl] = "public";
- }
-
- if (lastModifiedDate.HasValue)
- {
- responseHeaders[HeaderNames.LastModified] = lastModifiedDate.Value.ToUniversalTime().ToString(HttpDateFormat, _enUSculture);
- }
- }
-
- /// <summary>
- /// Adds the age header.
- /// </summary>
- /// <param name="responseHeaders">The responseHeaders.</param>
- /// <param name="lastDateModified">The last date modified.</param>
- private static void AddAgeHeader(IDictionary<string, string> responseHeaders, DateTime? lastDateModified)
- {
- if (lastDateModified.HasValue)
- {
- responseHeaders[HeaderNames.Age] = Convert.ToInt64((DateTime.UtcNow - lastDateModified.Value).TotalSeconds).ToString(CultureInfo.InvariantCulture);
- }
- }
-
- /// <summary>
- /// Determines whether [is not modified] [the specified if modified since].
- /// </summary>
- /// <param name="ifModifiedSince">If modified since.</param>
- /// <param name="cacheDuration">Duration of the cache.</param>
- /// <param name="dateModified">The date modified.</param>
- /// <returns><c>true</c> if [is not modified] [the specified if modified since]; otherwise, <c>false</c>.</returns>
- private bool IsNotModified(DateTime ifModifiedSince, TimeSpan? cacheDuration, DateTime? dateModified)
- {
- if (dateModified.HasValue)
- {
- var lastModified = NormalizeDateForComparison(dateModified.Value);
- ifModifiedSince = NormalizeDateForComparison(ifModifiedSince);
-
- return lastModified <= ifModifiedSince;
- }
-
- if (cacheDuration.HasValue)
- {
- var cacheExpirationDate = ifModifiedSince.Add(cacheDuration.Value);
-
- if (DateTime.UtcNow < cacheExpirationDate)
- {
- return true;
- }
- }
-
- return false;
- }
-
-
- /// <summary>
- /// When the browser sends the IfModifiedDate, it's precision is limited to seconds, so this will account for that.
- /// </summary>
- /// <param name="date">The date.</param>
- /// <returns>DateTime.</returns>
- private static DateTime NormalizeDateForComparison(DateTime date)
- {
- return new DateTime(date.Year, date.Month, date.Day, date.Hour, date.Minute, date.Second, date.Kind);
- }
-
- /// <summary>
- /// Adds the response headers.
- /// </summary>
- /// <param name="hasHeaders">The has options.</param>
- /// <param name="responseHeaders">The response headers.</param>
- private static void AddResponseHeaders(IHasHeaders hasHeaders, IEnumerable<KeyValuePair<string, string>> responseHeaders)
- {
- foreach (var item in responseHeaders)
- {
- hasHeaders.Headers[item.Key] = item.Value;
- }
- }
- }
-}