An HTTP response, minus any caching information.
Beispiel #1
0
 private ActionComponentSetup getExportAction(IEnumerable <object> headers, List <IEnumerable <object> > tableData) =>
 new ButtonSetup(
     "Export",
     behavior: new PostBackBehavior(
         postBack: PostBack.CreateFull(
             id: PostBack.GetCompositeId(setup.PostBackIdBase, "export"),
             actionGetter: () => new PostBackAction(
                 new PageReloadBehavior(
                     secondaryResponse: new SecondaryResponse(
                         () => EwfResponse.Create(
                             ContentTypes.Csv,
                             new EwfResponseBodyCreator(
                                 writer => {
     var csv = new CsvFileWriter();
     csv.AddValuesToLine(headers.ToArray());
     csv.WriteCurrentLineToFile(writer);
     foreach (var td in tableData)
     {
         csv.AddValuesToLine(td.ToArray());
         csv.WriteCurrentLineToFile(writer);
     }
 }),
                             () => "{0} {1}".FormatWith(
                                 setup.ExportFileName,
                                 AppRequestState.RequestTime.InZone(DateTimeZoneProviders.Tzdb.GetSystemDefault()).ToDateTimeUnspecified()) +
                             FileExtensions.Csv)))))));
Beispiel #2
0
        private Block getExportButton(IEnumerable <object> headers, List <IEnumerable <object> > tableData)
        {
            var block =
                new Block(
                    new PostBackButton(
                        PostBack.CreateFull(
                            id: PostBack.GetCompositeId(setup.PostBackIdBase, "export"),
                            actionGetter: () => new PostBackAction(
                                new SecondaryResponse(
                                    () => EwfResponse.Create(
                                        ContentTypes.Csv,
                                        new EwfResponseBodyCreator(
                                            writer => {
                var csv = new CsvFileWriter();
                csv.AddValuesToLine(headers.ToArray());
                csv.WriteCurrentLineToFile(writer);
                foreach (var td in tableData)
                {
                    csv.AddValuesToLine(td.ToArray());
                    csv.WriteCurrentLineToFile(writer);
                }
            }),
                                        () => "{0} {1}".FormatWith(setup.ExportFileName, DateTime.Now) + FileExtensions.Csv)))),
                        new TextActionControlStyle("Export"),
                        usesSubmitBehavior: false));

            block.Style.Add("text-align", "right");
            return(block);
        }
Beispiel #3
0
        /// <summary>
        /// Creates a response writer with CSS text.
        /// </summary>
        /// <param name="cssGetter">A function that gets the CSS that will be preprocessed and used as the response. Do not pass or return null.</param>
        /// <param name="urlVersionString">The resource-version string from the request URL. Do not pass null or the empty string; this parameter is required
        /// because it greatly improves cacheability, which is important for CSS. You must change the URL when the CSS changes, and you must not vary the response
        /// based on non-URL elements of the request, such as the authenticated user.</param>
        /// <param name="memoryCachingSetupGetter">A function that gets the memory-caching setup object for the response. Do not pass or return null; memory caching
        /// is important for CSS and is therefore required.</param>
        public EwfSafeResponseWriter(Func <string> cssGetter, string urlVersionString, Func <ResponseMemoryCachingSetup> memoryCachingSetupGetter)
        {
            var memoryCachingSetup = new Lazy <ResponseMemoryCachingSetup>(memoryCachingSetupGetter);

            writer = createWriter(
                () => EwfResponse.Create(ContentTypes.Css, new EwfResponseBodyCreator(() => CssPreprocessor.TransformCssFile(cssGetter()))),
                urlVersionString,
                "",
                () => memoryCachingSetup.Value.LastModificationDateAndTime,
                () => memoryCachingSetup.Value.CacheKey);
        }
Beispiel #4
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        protected sealed override EwfSafeRequestHandler getOrHead()
        {
            var extensionIndex = relativeFilePath.LastIndexOf('.');

            if (extensionIndex < 0)
            {
                throw new ResourceNotAvailableException("Failed to find the extension in the file path.", null);
            }
            var extension = relativeFilePath.Substring(extensionIndex);

            var mediaTypeOverride = EwfApp.Instance.GetMediaTypeOverrides().SingleOrDefault(i => i.FileExtension == extension);
            var contentType       = mediaTypeOverride != null ? mediaTypeOverride.MediaType : MimeTypeMap.GetMimeType(extension);

            var urlVersionString = isVersioned ? "invariant" : "";

            string getCacheKey() => "staticFile-{0}-{1}".FormatWith(isFrameworkFile, relativeFilePath);

            EwfSafeResponseWriter responseWriter;

            if (contentType == TewlContrib.ContentTypes.Css)
            {
                Func <string> cssGetter = () => File.ReadAllText(filePath);
                responseWriter = urlVersionString.Any()
                                                         ? new EwfSafeResponseWriter(
                    cssGetter,
                    urlVersionString,
                    () => new ResponseMemoryCachingSetup(getCacheKey(), GetResourceLastModificationDateAndTime()))
                                                         : new EwfSafeResponseWriter(
                    () => EwfResponse.Create(
                        TewlContrib.ContentTypes.Css,
                        new EwfResponseBodyCreator(() => CssPreprocessor.TransformCssFile(cssGetter()))),
                    GetResourceLastModificationDateAndTime(),
                    memoryCacheKeyGetter: getCacheKey);
            }
            else
            {
                Func <EwfResponse> responseCreator = () => EwfResponse.Create(
                    contentType,
                    new EwfResponseBodyCreator(
                        responseStream => {
                    using (var fileStream = File.OpenRead(filePath))
                        fileStream.CopyTo(responseStream);
                }));
                responseWriter = urlVersionString.Any()
                                                         ? new EwfSafeResponseWriter(
                    responseCreator,
                    urlVersionString,
                    memoryCachingSetupGetter: () => new ResponseMemoryCachingSetup(getCacheKey(), GetResourceLastModificationDateAndTime()))
                                                         : new EwfSafeResponseWriter(responseCreator, GetResourceLastModificationDateAndTime(), memoryCacheKeyGetter: getCacheKey);
            }
            return(responseWriter);
        }
Beispiel #5
0
 internal EwfResponse GetResponse()
 {
     return(EwfResponse.Create(
                file.ContentType,
                new EwfResponseBodyCreator(
                    () => {
         var contents = BlobFileOps.SystemProvider.GetFileContents(file.FileId);
         if (forcedImageWidth.Value.HasValue)
         {
             contents = EwlStatics.ResizeImage(contents, forcedImageWidth.Value.Value);
         }
         return contents;
     }),
                fileNameCreator: () => processAsAttachment.Value ? file.FileName : ""));
 }
Beispiel #6
0
        internal static void WriteRedirectResponse(HttpContext context, string url, bool permanent)
        {
            context.Response.StatusCode = permanent ? 308 : 307;

            if (context.Request.HttpMethod == "GET" || context.Request.HttpMethod == "HEAD")
            {
                EwfSafeResponseWriter.AddCacheControlHeader(
                    context.Response,
                    EwfApp.Instance.RequestIsSecure(context.Request),
                    false,
                    permanent ? (bool?)null : false);
            }

            EwfResponse.Create(
                ContentTypes.PlainText,
                new EwfResponseBodyCreator(writer => writer.Write("{0} Redirect: {1}".FormatWith(permanent ? "Permanent" : "Temporary", url))),
                additionalHeaderFieldGetter: () => ("Location", url).ToCollection())
            .WriteToAspNetResponse(context.Response, omitBody: context.Request.HttpMethod == "HEAD");
        }
Beispiel #7
0
        private static Action <HttpRequest, HttpResponse> createWriter(
            Func <EwfResponse> responseCreator, string urlVersionString, string eTagBase, Func <DateTimeOffset> lastModificationDateAndTimeGetter,
            Func <string> memoryCacheKeyGetter)
        {
            return((aspNetRequest, aspNetResponse) => {
                // Disable ASP.NET output caching.
                aspNetResponse.Cache.SetNoServerCaching();

                var response = new Lazy <EwfResponse>(responseCreator);

                // If we ever want to implement content negotiation, we can do so here. We can accept multiple response-creator functions instead of just one. Then, if
                // the request contains an Accept header, we can evaluate the response-creator functions here and then choose the response with the best content type.
                // If there is no match, we can send a 406 (Not Acceptable) status code and exit the method. Note that if we do add support for multiple
                // response-creator functions, we need to incorporate the chosen response's content type into the ETag if we want it to remain a strong ETag. We also
                // need to incorporate the content type into the memory-cache key.

                // Assume that all HTTPS responses are private. This isn't true for CSS, JavaScript, etc. requests that are only secure in order to match the security
                // of a page, but that's not a big deal since most shared caches can't open and cache HTTPS anyway.
                //
                // If we don't have caching information, the response is probably not shareable.
                //
                // Using ServerAndPrivate instead of just Private is a hack that is necessary because ASP.NET suppresses ETags with Private. But ASP.NET output caching
                // (i.e. server caching) will still be disabled because of our SetNoServerCaching call above.
                aspNetResponse.Cache.SetCacheability(
                    !EwfApp.Instance.RequestIsSecure(aspNetRequest) && (urlVersionString.Any() || eTagBase.Any() || lastModificationDateAndTimeGetter != null)
                                                ? HttpCacheability.Public
                                                : HttpCacheability.ServerAndPrivate);

                aspNetResponse.Cache.SetMaxAge(urlVersionString.Any() ? TimeSpan.FromDays(365) : TimeSpan.Zero);

                var lastModificationDateAndTime = lastModificationDateAndTimeGetter != null ? new Lazy <DateTimeOffset>(lastModificationDateAndTimeGetter) : null;
                string eTag;
                if (urlVersionString.Any())
                {
                    eTag = urlVersionString;
                }
                else if (eTagBase.Any() || lastModificationDateAndTimeGetter != null)
                {
                    eTag = eTagBase + (lastModificationDateAndTimeGetter != null ? GetUrlVersionString(lastModificationDateAndTime.Value) : "");
                }
                else
                {
                    // Buffer the response body.
                    var responseWithBufferedBody = EwfResponse.Create(
                        response.Value.ContentType,
                        response.Value.BodyCreator.GetBufferedBodyCreator(),
                        fileNameCreator: response.Value.FileNameCreator);
                    response = new Lazy <EwfResponse>(() => responseWithBufferedBody);

                    var bodyAsBinary = response.Value.BodyCreator.BodyIsText
                                                                   ? Encoding.UTF8.GetBytes(response.Value.BodyCreator.TextBodyCreator())
                                                                   : response.Value.BodyCreator.BinaryBodyCreator();
                    eTag = Convert.ToBase64String(MD5.Create().ComputeHash(bodyAsBinary));
                }

                // Strong ETags must vary by content coding. Since we don't know yet how this response will be encoded (gzip or otherwise), the best thing we can do is
                // use the Accept-Encoding header value in the ETag.
                var acceptEncoding = aspNetRequest.Headers["Accept-Encoding"];                   // returns null if field missing
                if (acceptEncoding != null)
                {
                    eTag += acceptEncoding.Replace(", ", "");                       // On 4 Feb 2015 we saw the comma/space cause Chrome to incorrectly split the ETag apart.
                }
                aspNetResponse.Cache.SetETag(eTag);

                // Sending a Last-Modified header isn't a good enough reason to force evaluation of lastModificationDateAndTimeGetter, which could be expensive.
                if (lastModificationDateAndTimeGetter != null && lastModificationDateAndTime.IsValueCreated)
                {
                    aspNetResponse.Cache.SetLastModified(lastModificationDateAndTime.Value.UtcDateTime);
                }

                // When we separate EWF from Web Forms, we may need to add a Vary header with "Accept-Encoding". Do that here.

                var ifNoneMatch = aspNetRequest.Headers.GetValues("If-None-Match");                   // returns null if field missing
                if (ifNoneMatch != null && ifNoneMatch.Contains(eTag))
                {
                    aspNetResponse.StatusCode = 304;
                    return;
                }

                var memoryCacheKey = memoryCacheKeyGetter();
                if (memoryCacheKey.Any())
                {
                    var fullResponse = FullResponse.GetFromCache(memoryCacheKey, lastModificationDateAndTime.Value, () => response.Value.CreateFullResponse());
                    response = new Lazy <EwfResponse>(() => new EwfResponse(fullResponse));
                }

                if (response.Value.ContentType.Length > 0)
                {
                    aspNetResponse.ContentType = response.Value.ContentType;
                }

                var fileName = response.Value.FileNameCreator();
                if (fileName.Any())
                {
                    aspNetResponse.AppendHeader("content-disposition", "attachment; filename=\"" + fileName + "\"");
                }

                if (aspNetRequest.HttpMethod != "HEAD")
                {
                    response.Value.BodyCreator.WriteToResponse(aspNetResponse);
                }
            });
        }
Beispiel #8
0
 /// <summary>
 /// Creates a response writer with a generic response and no caching information.
 /// </summary>
 /// <param name="response">The response.</param>
 public EwfSafeResponseWriter(EwfResponse response)
 {
     writer = createWriter(() => response, "", "", null, () => "");
 }
 /// <summary>
 /// Creates a response writer with a generic response and no caching information.
 /// </summary>
 /// <param name="response">The response.</param>
 public EwfSafeResponseWriter( EwfResponse response )
 {
     writer = createWriter( () => response, "", "", null, () => "" );
 }
        private static Action<HttpRequest, HttpResponse> createWriter(
            Func<EwfResponse> responseCreator, string urlVersionString, string eTagBase, Func<DateTimeOffset> lastModificationDateAndTimeGetter,
            Func<string> memoryCacheKeyGetter)
        {
            return ( aspNetRequest, aspNetResponse ) => {
                // Disable ASP.NET output caching.
                aspNetResponse.Cache.SetNoServerCaching();

                var response = new Lazy<EwfResponse>( responseCreator );

                // If we ever want to implement content negotiation, we can do so here. We can accept multiple response-creator functions instead of just one. Then, if
                // the request contains an Accept header, we can evaluate the response-creator functions here and then choose the response with the best content type.
                // If there is no match, we can send a 406 (Not Acceptable) status code and exit the method. Note that if we do add support for multiple
                // response-creator functions, we need to incorporate the chosen response's content type into the ETag if we want it to remain a strong ETag. We also
                // need to incorporate the content type into the memory-cache key.

                // Assume that all HTTPS responses are private. This isn't true for CSS, JavaScript, etc. requests that are only secure in order to match the security
                // of a page, but that's not a big deal since most shared caches can't open and cache HTTPS anyway.
                //
                // If we don't have caching information, the response is probably not shareable.
                //
                // Using ServerAndPrivate instead of just Private is a hack that is necessary because ASP.NET suppresses ETags with Private. But ASP.NET output caching
                // (i.e. server caching) will still be disabled because of our SetNoServerCaching call above.
                aspNetResponse.Cache.SetCacheability(
                    !EwfApp.Instance.RequestIsSecure( aspNetRequest ) && ( urlVersionString.Any() || eTagBase.Any() || lastModificationDateAndTimeGetter != null )
                        ? HttpCacheability.Public
                        : HttpCacheability.ServerAndPrivate );

                aspNetResponse.Cache.SetMaxAge( urlVersionString.Any() ? TimeSpan.FromDays( 365 ) : TimeSpan.Zero );

                var lastModificationDateAndTime = lastModificationDateAndTimeGetter != null ? new Lazy<DateTimeOffset>( lastModificationDateAndTimeGetter ) : null;
                string eTag;
                if( urlVersionString.Any() )
                    eTag = urlVersionString;
                else if( eTagBase.Any() || lastModificationDateAndTimeGetter != null )
                    eTag = eTagBase + ( lastModificationDateAndTimeGetter != null ? GetUrlVersionString( lastModificationDateAndTime.Value ) : "" );
                else {
                    // Buffer the response body.
                    var responseWithBufferedBody = new EwfResponse(
                        response.Value.ContentType,
                        response.Value.BodyCreator.GetBufferedBodyCreator(),
                        fileNameCreator: response.Value.FileNameCreator );
                    response = new Lazy<EwfResponse>( () => responseWithBufferedBody );

                    var bodyAsBinary = response.Value.BodyCreator.BodyIsText
                                           ? Encoding.UTF8.GetBytes( response.Value.BodyCreator.TextBodyCreator() )
                                           : response.Value.BodyCreator.BinaryBodyCreator();
                    eTag = Convert.ToBase64String( MD5.Create().ComputeHash( bodyAsBinary ) );
                }

                // Strong ETags must vary by content coding. Since we don't know yet how this response will be encoded (gzip or otherwise), the best thing we can do is
                // use the Accept-Encoding header value in the ETag.
                var acceptEncoding = aspNetRequest.Headers[ "Accept-Encoding" ]; // returns null if field missing
                if( acceptEncoding != null )
                    eTag += acceptEncoding.Replace( ", ", "" ); // On 4 Feb 2015 we saw the comma/space cause Chrome to incorrectly split the ETag apart.

                aspNetResponse.Cache.SetETag( eTag );

                // Sending a Last-Modified header isn't a good enough reason to force evaluation of lastModificationDateAndTimeGetter, which could be expensive.
                if( lastModificationDateAndTimeGetter != null && lastModificationDateAndTime.IsValueCreated )
                    aspNetResponse.Cache.SetLastModified( lastModificationDateAndTime.Value.UtcDateTime );

                // When we separate EWF from Web Forms, we may need to add a Vary header with "Accept-Encoding". Do that here.

                var ifNoneMatch = aspNetRequest.Headers.GetValues( "If-None-Match" ); // returns null if field missing
                if( ifNoneMatch != null && ifNoneMatch.Contains( eTag ) ) {
                    aspNetResponse.StatusCode = 304;
                    return;
                }

                var memoryCacheKey = memoryCacheKeyGetter();
                if( memoryCacheKey.Any() ) {
                    var fullResponse = FullResponse.GetFromCache( memoryCacheKey, lastModificationDateAndTime.Value, () => response.Value.CreateFullResponse() );
                    response = new Lazy<EwfResponse>( () => new EwfResponse( fullResponse ) );
                }

                if( response.Value.ContentType.Length > 0 )
                    aspNetResponse.ContentType = response.Value.ContentType;

                var fileName = response.Value.FileNameCreator();
                if( fileName.Any() )
                    aspNetResponse.AppendHeader( "content-disposition", "attachment; filename=\"" + fileName + "\"" );

                if( aspNetRequest.HttpMethod != "HEAD" )
                    response.Value.BodyCreator.WriteToResponse( aspNetResponse );
            };
        }
        void IHttpHandler.ProcessRequest(HttpContext context)
        {
            var url = EwfApp.GetRequestAppRelativeUrl(context.Request);

            var queryIndex = url.IndexOf("?", StringComparison.Ordinal);

            if (queryIndex >= 0)
            {
                url = url.Remove(queryIndex);
            }

            var extensionIndex = url.LastIndexOf(".", StringComparison.Ordinal);

            var versionStringOrFileExtensionIndex = extensionIndex;
            var urlVersionString = "";

            if (url.StartsWith(VersionedFilesFolderName + "/") || url.StartsWith(EwfFolderName + "/" + VersionedFilesFolderName + "/"))
            {
                urlVersionString = "invariant";
            }
            else
            {
                // We assume that all URL version strings will have the same length as the format string.
                var prefixedVersionStringIndex = extensionIndex - (urlVersionStringPrefix.Length + EwfSafeResponseWriter.UrlVersionStringFormat.Length);

                if (prefixedVersionStringIndex >= 0)
                {
                    DateTimeOffset dateAndTime;
                    var            versionString = url.Substring(prefixedVersionStringIndex + urlVersionStringPrefix.Length, EwfSafeResponseWriter.UrlVersionStringFormat.Length);
                    if (DateTimeOffset.TryParseExact(
                            versionString,
                            EwfSafeResponseWriter.UrlVersionStringFormat,
                            DateTimeFormatInfo.InvariantInfo,
                            DateTimeStyles.None,
                            out dateAndTime))
                    {
                        versionStringOrFileExtensionIndex = prefixedVersionStringIndex;
                        urlVersionString = versionString;
                    }
                }
            }

            if (versionStringOrFileExtensionIndex < 0)
            {
                throw new ResourceNotAvailableException("Failed to find the extension in the URL.", null);
            }
            var extension      = url.Substring(extensionIndex);
            var staticFileInfo =
                EwfApp.GlobalType.Assembly.CreateInstance(
                    CombineNamespacesAndProcessEwfIfNecessary(
                        EwfApp.GlobalType.Namespace,
                        (url.Remove(versionStringOrFileExtensionIndex) + extension.CapitalizeString()).Separate("/", false)
                        .Select(i => EwlStatics.GetCSharpIdentifier(i.CapitalizeString()))
                        .Aggregate((a, b) => a + "." + b) + "+Info")) as StaticFileInfo;

            if (staticFileInfo == null)
            {
                throw new ResourceNotAvailableException("Failed to create an Info object for the request.", null);
            }

            var mediaTypeOverride = EwfApp.Instance.GetMediaTypeOverrides().SingleOrDefault(i => i.FileExtension == extension);
            var contentType       = mediaTypeOverride != null ? mediaTypeOverride.MediaType : MimeTypeMap.GetMimeType(extension);

            Func <string>         cacheKeyGetter = () => staticFileInfo.GetUrl(false, false, false);
            EwfSafeResponseWriter responseWriter;

            if (contentType == ContentTypes.Css)
            {
                Func <string> cssGetter = () => File.ReadAllText(staticFileInfo.FilePath);
                responseWriter = urlVersionString.Any()
                                                         ? new EwfSafeResponseWriter(
                    cssGetter,
                    urlVersionString,
                    () => new ResponseMemoryCachingSetup(cacheKeyGetter(), staticFileInfo.GetResourceLastModificationDateAndTime()))
                                                         : new EwfSafeResponseWriter(
                    () => EwfResponse.Create(ContentTypes.Css, new EwfResponseBodyCreator(() => CssPreprocessor.TransformCssFile(cssGetter()))),
                    staticFileInfo.GetResourceLastModificationDateAndTime(),
                    memoryCacheKeyGetter: cacheKeyGetter);
            }
            else
            {
                Func <EwfResponse> responseCreator = () => EwfResponse.Create(
                    contentType,
                    new EwfResponseBodyCreator(
                        responseStream => {
                    using (var fileStream = File.OpenRead(staticFileInfo.FilePath))
                        fileStream.CopyTo(responseStream);
                }));
                responseWriter = urlVersionString.Any()
                                                         ? new EwfSafeResponseWriter(
                    responseCreator,
                    urlVersionString,
                    memoryCachingSetupGetter:
                    () => new ResponseMemoryCachingSetup(cacheKeyGetter(), staticFileInfo.GetResourceLastModificationDateAndTime()))
                                                         : new EwfSafeResponseWriter(
                    responseCreator,
                    staticFileInfo.GetResourceLastModificationDateAndTime(),
                    memoryCacheKeyGetter: cacheKeyGetter);
            }
            responseWriter.WriteResponse();
        }
Beispiel #12
0
        private static Action <HttpResponse, HttpRequest, bool> createWriter(
            Func <EwfResponse> responseCreator, string urlVersionString, string eTagBase, Func <DateTimeOffset> lastModificationDateAndTimeGetter,
            Func <string> memoryCacheKeyGetter)
        {
            return((aspNetResponse, aspNetRequest, forceImmediateResponseExpiration) => {
                var response = new Lazy <EwfResponse>(responseCreator);

                // If we ever want to implement content negotiation, we can do so here. We can accept multiple response-creator functions instead of just one. Then, if
                // the request contains an Accept header, we can evaluate the response-creator functions here and then choose the response with the best content type.
                // If there is no match, we can send a 406 (Not Acceptable) status code and exit the method. Note that if we do add support for multiple
                // response-creator functions, we need to incorporate the chosen response's content type into the ETag if we want it to remain a strong ETag. We also
                // need to incorporate the content type into the memory-cache key.

                AddCacheControlHeader(
                    aspNetResponse,
                    EwfApp.Instance.RequestIsSecure(aspNetRequest),
                    urlVersionString.Any() || eTagBase.Any() || lastModificationDateAndTimeGetter != null,
                    urlVersionString.Any() && !forceImmediateResponseExpiration);

                var lastModificationDateAndTime = lastModificationDateAndTimeGetter != null ? new Lazy <DateTimeOffset>(lastModificationDateAndTimeGetter) : null;
                string eTag;
                if (urlVersionString.Any())
                {
                    eTag = urlVersionString;
                }
                else if (eTagBase.Any() || lastModificationDateAndTimeGetter != null)
                {
                    eTag = eTagBase + (lastModificationDateAndTimeGetter != null ? GetUrlVersionString(lastModificationDateAndTime.Value) : "");
                }
                else
                {
                    // Buffer the response body.
                    var responseWithBufferedBody = EwfResponse.Create(
                        response.Value.ContentType,
                        response.Value.BodyCreator.GetBufferedBodyCreator(),
                        fileNameCreator: response.Value.FileNameCreator,
                        additionalHeaderFieldGetter: response.Value.AdditionalHeaderFieldGetter);
                    response = new Lazy <EwfResponse>(() => responseWithBufferedBody);

                    var bodyAsBinary = response.Value.BodyCreator.BodyIsText
                                                                   ? Encoding.UTF8.GetBytes(response.Value.BodyCreator.TextBodyCreator())
                                                                   : response.Value.BodyCreator.BinaryBodyCreator();
                    eTag = Convert.ToBase64String(MD5.Create().ComputeHash(bodyAsBinary));
                }

                // Strong ETags must vary by content coding. Since we don't know yet how this response will be encoded (gzip or otherwise), the best thing we can do is
                // use the Accept-Encoding header value in the ETag.
                var acceptEncoding = aspNetRequest.Headers["Accept-Encoding"];                   // returns null if field missing
                if (acceptEncoding != null)
                {
                    eTag += acceptEncoding.Replace(", ", "");                       // On 4 Feb 2015 we saw the comma/space cause Chrome to incorrectly split the ETag apart.
                }
                aspNetResponse.Cache.SetETag(eTag);

                // Sending a Last-Modified header isn't a good enough reason to force evaluation of lastModificationDateAndTimeGetter, which could be expensive.
                if (lastModificationDateAndTimeGetter != null && lastModificationDateAndTime.IsValueCreated)
                {
                    aspNetResponse.Cache.SetLastModified(lastModificationDateAndTime.Value.UtcDateTime);
                }

                // When we separate EWF from Web Forms, we may need to add a Vary header with "Accept-Encoding". Do that here.

                var ifNoneMatch = aspNetRequest.Headers.GetValues("If-None-Match");                   // returns null if field missing
                if (ifNoneMatch != null && ifNoneMatch.Contains(eTag))
                {
                    aspNetResponse.StatusCode = 304;
                    return;
                }

                var memoryCacheKey = memoryCacheKeyGetter();
                if (memoryCacheKey.Any())
                {
                    var fullResponse = FullResponse.GetFromCache(memoryCacheKey, lastModificationDateAndTime.Value, () => response.Value.CreateFullResponse());
                    response = new Lazy <EwfResponse>(() => new EwfResponse(fullResponse));
                }

                response.Value.WriteToAspNetResponse(aspNetResponse, omitBody: aspNetRequest.HttpMethod == "HEAD");
            });
        }
Beispiel #13
0
 protected override EwfSafeRequestHandler getOrHead() =>
 new EwfSafeResponseWriter(
     EwfResponse.Create(ContentTypes.PlainText, new EwfResponseBodyCreator(() => new JavaScriptSerializer().Serialize(getItems()))));