如何将捆绑和缩小的文件上传到 Windows Azure CDN

Question

我在 Microsoft.AspNet.Web.Optimization 命名空间（例如 @Styles.Render("~/content/static/css")）中使用 ASP.NET MVC 4 捆绑和缩小功能。

我想将它与 Windows Azure CDN 结合使用。

我考虑编写自定义 BundleTransform，但内容尚未优化。

我还研究了在运行时解析和上传优化的流，但这对我来说就像是 hack，我不太喜欢它：

@StylesCdn.Render(Url.AbsoluteContent(
    Styles.Url("~/content/static/css").ToString()
    ));

public static IHtmlString Render(string absolutePath)
{
    // get the version hash
    string versionHash = HttpUtility.ParseQueryString(
        new Uri(absolutePath).Query
        ).Get("v");

    // only parse and upload to CDN if version hash is different
    if (versionHash != _versionHash)
    {
        _versionHash = versionHash;

        WebClient client = new WebClient();
        Stream stream = client.OpenRead(absolutePath);

        UploadStreamToAzureCdn(stream);
    }

    var styleSheetLink = String.Format(
        "<link href=\"{0}://{1}/{2}/{3}?v={4}\" rel=\"stylesheet\" type=\"text/css\" />",
        cdnEndpointProtocol, cdnEndpointUrl, cdnContainer, cdnCssFileName, versionHash
        );

    return new HtmlString(styleSheetLink);
}

如何将捆绑和缩小的版本自动上传到我的 Windows Azure CDN？

Answer 1

您可以定义origin domain as Azure's website（这可能是在原始问题之后很久才添加的）。

一旦你有了 CDN 端点，你需要允许它的查询字符串，然后你可以通过 CDN 直接引用包：

<link href="//az888888.vo.msecnd.net/Content/css-common?v=ioYVnAg-Q3qYl3Pmki-qdKwT20ESkdREhi4DsEehwCY1" rel="stylesheet"/>

我还创建了这个助手来附加 CDN 主机名：

public static IHtmlString RenderScript(string virtualPath)
{
    if (HttpContext.Current.IsDebuggingEnabled)
        return Scripts.Render(virtualPath);
    else
        return new HtmlString(String.Format(
            CultureInfo.InvariantCulture, 
            Scripts.DefaultTagFormat, 
            "//CDN_HOST" + Scripts.Url(virtualPath).ToHtmlString()));
}

Answer 2

对于@manishKungwani 在之前的评论中要求。只需设置 UseCdn 然后使用 cdnHost 重载以创建捆绑包。我用它来放入 AWS CloudFront 域 (xxx.cloudfront.net)，但事后看来，它应该被更通用地命名以与任何其他 CDN 提供商一起使用。

public class CloudFrontScriptBundle : Bundle
{
    public CloudFrontScriptBundle(string virtualPath, string cdnHost = "")
        : base(virtualPath, null, new IBundleTransform[] { new JsMinify(), new CloudFrontBundleTransformer { CdnHost = cdnHost } })
    {
        ConcatenationToken = ";";
    }
}

public class CloudFrontStyleBundle : Bundle
{
    public CloudFrontStyleBundle(string virtualPath, string cdnHost = "")
        : base(virtualPath, null, new IBundleTransform[] { new CssMinify(), new CloudFrontBundleTransformer { CdnHost = cdnHost } })
    {
    }
}

public class CloudFrontBundleTransformer : IBundleTransform
{
    public string CdnHost { get; set; }

    static CloudFrontBundleTransformer()
    {
    }

    public virtual void Process(BundleContext context, BundleResponse response)
    {
        if (context.BundleCollection.UseCdn && !String.IsNullOrWhiteSpace(CdnHost))
        {
            var virtualFileName = VirtualPathUtility.GetFileName(context.BundleVirtualPath);
            var virtualDirectory = VirtualPathUtility.GetDirectory(context.BundleVirtualPath);

            if (!String.IsNullOrEmpty(virtualDirectory))
                virtualDirectory = virtualDirectory.Trim('~');

            var uri = string.Format("//{0}{1}{2}", CdnHost, virtualDirectory, virtualFileName);
            using (var hashAlgorithm = CreateHashAlgorithm())
            {
                var hash = HttpServerUtility.UrlTokenEncode(hashAlgorithm.ComputeHash(Encoding.Unicode.GetBytes(response.Content)));
                context.BundleCollection.GetBundleFor(context.BundleVirtualPath).CdnPath = string.Format("{0}?v={1}", uri, hash);
            }
        }
    }

    private static SHA256 CreateHashAlgorithm()
    {
        if (CryptoConfig.AllowOnlyFipsAlgorithms)
        {
            return new SHA256CryptoServiceProvider();
        }

        return new SHA256Managed();
    }
}

Answer 3

按照 Hao 的建议，我扩展了 Bundle 和 IBundleTransform。

将 AzureScriptBundle 或 AzureStyleBundle 添加到包中；

bundles.Add(new AzureScriptBundle("~/bundles/modernizr.js", "cdn").Include("~/Scripts/vendor/modernizr.custom.68789.js"));

结果；

<script src="//127.0.0.1:10000/devstoreaccount1/cdn/modernizr.js?v=g-XPguHFgwIb6tGNcnvnI_VY_ljCYf2BDp_NS5X7sAo1"></script>

如果未设置 CdnHost，它将使用 blob 的 Uri 而不是 CDN。

类

using System;
using System.Text;
using System.Web;
using System.Web.Optimization;
using System.Security.Cryptography;
using Microsoft.WindowsAzure;
using Microsoft.WindowsAzure.ServiceRuntime;
using Microsoft.WindowsAzure.StorageClient;

namespace SiegeEngineWebRole.BundleExtentions
{
    public class AzureScriptBundle : Bundle
    {
        public AzureScriptBundle(string virtualPath, string containerName, string cdnHost = "")
            : base(virtualPath, null, new IBundleTransform[] { new JsMinify(), new AzureBlobUpload { ContainerName = containerName, CdnHost = cdnHost } })
        {
            ConcatenationToken = ";";
        }
    }

    public class AzureStyleBundle : Bundle
    {
        public AzureStyleBundle(string virtualPath, string containerName, string cdnHost = "")
            : base(virtualPath, null, new IBundleTransform[] { new CssMinify(), new AzureBlobUpload { ContainerName = containerName, CdnHost = cdnHost } })
        {
        }
    }

    public class AzureBlobUpload : IBundleTransform
    {
        public string ContainerName { get; set; }
        public string CdnHost { get; set; }

        static AzureBlobUpload()
        {
        }

        public virtual void Process(BundleContext context, BundleResponse response)
        {
            var file = VirtualPathUtility.GetFileName(context.BundleVirtualPath);

            if (!context.BundleCollection.UseCdn)
            {
                return;
            }
            if (string.IsNullOrWhiteSpace(ContainerName))
            {
                throw new Exception("ContainerName Not Set");
            }

            var conn = CloudStorageAccount.Parse(RoleEnvironment.GetConfigurationSettingValue("DataConnectionString"));
            var blob = conn.CreateCloudBlobClient()
                .GetContainerReference(ContainerName)
                .GetBlobReference(file);

            blob.Properties.ContentType = response.ContentType;
            blob.UploadText(response.Content);

            var uri = string.IsNullOrWhiteSpace(CdnHost) ? blob.Uri.AbsoluteUri.Replace("http:", "").Replace("https:", "") : string.Format("//{0}/{1}/{2}", CdnHost, ContainerName, file);

            using (var hashAlgorithm = CreateHashAlgorithm())
            {
                var hash = HttpServerUtility.UrlTokenEncode(hashAlgorithm.ComputeHash(Encoding.Unicode.GetBytes(response.Content)));
                context.BundleCollection.GetBundleFor(context.BundleVirtualPath).CdnPath = string.Format("{0}?v={1}", uri, hash);
            }
        }

        private static SHA256 CreateHashAlgorithm()
        {
            if (CryptoConfig.AllowOnlyFipsAlgorithms)
            {
                return new SHA256CryptoServiceProvider();
            }

            return new SHA256Managed();
        }
    }
}

Answer 4

所以目前没有很好的方法来做到这一点。我们设想的长期工作流程是添加构建时捆绑支持。然后，您将运行构建任务（如果您愿意，也可以运行 exe）来生成捆绑包，然后能够将它们上传到 AzureCDN。最后，您只需在 BundleCollection 上打开 UseCDN，脚本/样式助手就会自动切换到渲染到您的 AzureCDN 的链接，并适当地回退到您的本地包。

就短期而言，我认为您正在尝试做的是在首次构建捆绑包时将捆绑包上传到 AzureCDN？

我猜 BundleTransform 是一种方法，它有点小技巧，但你可以在你的包中最后添加一个 BundleTransform。自上次以来，BundleResponse.Content 实际上是最终的捆绑响应。届时，您可以将其上传到您的 CDN。这有意义吗？