c# - 如何在 Windows Azure 中为 Blob 存储配置 CORS 设置

Question

我在 azure 存储中创建了多个容器，并将一些文件上传到这些容器中。现在我需要授予对容器/blob 的域级别访问权限。所以我从代码级别进行了尝试，如下所示。

        CloudStorageAccount storageAccount = CloudStorageAccount.Parse(
        CloudConfigurationManager.GetSetting("StorageConnectionString"));

        CloudBlobClient blobClient = storageAccount.CreateCloudBlobClient();
        ServiceProperties blobServiceProperties = new ServiceProperties();
            blobServiceProperties.Cors.CorsRules.Add(new CorsRule(){
                AllowedHeaders = new List<string>() {"*"},
                ExposedHeaders = new List<string>() {"*"},
                AllowedMethods = CorsHttpMethods.Post | CorsHttpMethods.Put | CorsHttpMethods.Get | CorsHttpMethods.Delete ,
                AllowedOrigins = new List<string>() { "http://localhost:8080/"},
                MaxAgeInSeconds = 3600,
            });

          blobClient.SetServiceProperties(GetBlobServiceProperties());  

但是如果我从代码创建所有内容，上面的代码似乎可以工作(如果我错了，请纠正我)。我还发现如下设置 Here ,

 <CorsRule>
  <AllowedOrigins>http://www.contoso.com, http://www.fabrikam.com</AllowedOrigins>
  <AllowedMethods>PUT,GET</AllowedMethods>
  <AllowedHeaders>x-ms-meta-data*,x-ms-meta-target,x-ms-meta-source</AllowedHeaders>
  <ExposedHeaders>x-ms-meta-*</ExposedHeaders>
  <MaxAgeInSeconds>200</MaxAgeInSeconds>
</CorsRule>

但是我不知道这段代码应该放在哪里。我的意思是在哪个文件中。或者从 azure 门户创建容器或 blob 时是否有任何 CORS 设置。请协助。任何帮助将不胜感激。谢谢!

Answer 1

下面回答了标题中实际提出的问题。看来提问者已经知道如何在很大程度上从他的代码中做到这一点，但这是我对此的回答。不幸的是，微软发布的代码示例远非简单或清晰，所以我希望这对其他人有帮助。在此解决方案中，您需要的只是一个 CloudStorageAccount 实例，您可以从那时起调用此函数(作为扩展方法)。

//用法:

        // -- example usage (in this case adding a wildcard CORS rule to this account --

        CloudStorageAccount acc = getYourStorageAccount();

        acc.SetCORSPropertiesOnBlobService(cors => {
            var wildcardRule = new CorsRule() { AllowedMethods = CorsHttpMethods.Get, AllowedOrigins = { "*" } };
            cors.CorsRules.Add(wildcardRule);
            return cors;
        });

//代码:

    /// <summary>
    /// Allows caller to replace or alter the current CorsProperties on a given CloudStorageAccount.
    /// </summary>
    /// <param name="storageAccount">Storage account.</param>
    /// <param name="alterCorsRules">The returned value will replace the 
    /// current ServiceProperties.Cors (ServiceProperties) value. </param>
    public static void SetCORSPropertiesOnBlobService(this CloudStorageAccount storageAccount,
        Func<CorsProperties, CorsProperties> alterCorsRules)
    {
        if (storageAccount == null || alterCorsRules == null) throw new ArgumentNullException();

        CloudBlobClient blobClient = storageAccount.CreateCloudBlobClient();

        ServiceProperties serviceProperties = blobClient.GetServiceProperties();

        serviceProperties.Cors = alterCorsRules(serviceProperties.Cors) ?? new CorsProperties();

        blobClient.SetServiceProperties(serviceProperties);
    }

考虑 CorsRule 类的属性可能会有所帮助:

        CorsRule corsRule = new CorsRule() {
            AllowedMethods = CorsHttpMethods.Get,       // Gets or sets the HTTP methods permitted to execute for this origin
            AllowedOrigins = { "*" },                   // (IList<string>) Gets or sets domain names allowed via CORS.
            //AllowedHeaders = { "*" },                 // (IList<string>) Gets or sets headers allowed to be part of the CORS request
            //ExposedHeaders = null,                    // (IList<string>) Gets or sets response headers that should be exposed to client via CORS
            //MaxAgeInSeconds = 33333                   // Gets or sets the length of time in seconds that a preflight response should be cached by browser
        };