爲Blob上傳並使用Azure REST-API SharedKey

Question

我們目前使用REST API（基於Microsoft示例）從.NET客戶端配置文件計算機上以塊爲單位上傳blob。 REST API示例直接使用Azure存儲帳戶名稱和訪問密鑰構建請求標頭中的SharedKey條目。對於生產代碼，我們需要在我們的服務器上計算SharedKey，並將其交付給客戶端以在會話期間使用。

blob的SharedKey創建示例爲我提供了一個Url plus查詢字符串，其中包含訪問參數。

我的問題：如何將此Url /查詢字符串鍵格式與Azure REST API所需的SharedKey標題條目結合使用？

任何指針或提示非常感謝！ R

Answer 1

在這裏你去。顯然可以對此代碼進行很多改進:)試試看。請讓我知道它是否適合你。

 
using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Text; 
using System.IO; 
using System.Web; 
using System.Net; 
using System.Collections.Specialized; 
using System.Globalization;
 

namespace UploadBlobUsingSASUrl { class Program { //This is part of SAS signature (query string). We will construct the URI later using this. private static string sasSignature = "sr=c&st=2012-08-16T14%3A38%3A48Z&se=2012-08-16T15%3A38%3A48Z&sp=w&sig=aNTLYQtwA1UmjG7j8Lg44t8YThL16FkNYBi54kl4ZKo%3D"; //Blob storage endpoint private static string blobStorageEndpoint = "http://127.0.0.1:10000/devstoreaccount1"; //Blob container name private static string blobContainerName = "[blob container name. SAS URI with Write permission must be created on this blob container]"; //File to upload private static string fileToUpload = @"[Full path of the file you wish to upload]"; //This is the default block size (This application always assumes that a file will be split in blocks and then uploaded). private static int blockSize = 256 * 1024;//256 KB //Storage service version (Unless you're using latest SAS related changes in cloud storage, use this version). For development storage always use this version. private static string x_ms_version = "2011-08-18"; //Template for put block list private static string blockListTemplate = @"{0}"; // Template for block id (to be included in put block list template) private static string blockIdTemplate = "{0}"; //We'll keep a list of block ids. private static List blockIds = new List(); static void Main(string[] args) {
 

     FileInfo file = new FileInfo(fileToUpload); 
     long totalFileSize = file.Length;//Get the file size 
     long bytesFrom = 0; 
     long bytesRemaining = totalFileSize; 
     string blobName = file.Name; 
     //This is the base URI which will be used for put blocks and put block list operations. 
     //It is essentially would be something like "http://127.0.0.1:10000/devstoreaccount1/myblobcontainer/myblobname?sassignature" 
     string baseUri = string.Format("{0}/{1}/{2}?{3}", blobStorageEndpoint, blobContainerName, blobName, sasSignature); 
     int counter = 0; 
     //In this loop, we'll read file in chunks and try and upload one chunk at a time. 
     while (true) 
     { 
      int bytesToRead = blockSize; 
      if (bytesRemaining < blockSize) 
      { 
       bytesToRead = (int)bytesRemaining; 
      } 
      //Read the file in chunks 
      byte[] fileContents = ReadFile(fileToUpload, bytesFrom, bytesToRead); 
      bytesRemaining -= fileContents.Length; 
      bytesFrom += fileContents.Length; 
      //Create block id 
      string blockId = string.Format("Block-{0:D5}", counter); 
      //Append that to the block id list. 
      blockIds.Add(blockId); 
      //Now let's upload the block. 
      var isBlockUploaded = UploadBlock(baseUri, fileContents, blockId); 
      Console.WriteLine("Block Id: " + blockId + " Block Size: " + fileContents.Length + " Uploaded: " + isBlockUploaded); 
      counter++; 
      if (bytesRemaining <= 0) 
      { 
       break; 
      } 
     } 
     //All blocks uploaded, now let's commit the block list 
     var isBlockListCommitted = CommitBlockList(baseUri, blockIds); 
     Console.WriteLine("Is Block List Committed: " + isBlockListCommitted); 
     Console.WriteLine("Press any key to terminate the program ...."); 
     Console.ReadLine(); 
    } 

    /// <summary> 
    /// This function reads a chunk of the file and returns that as byte array. 
    /// </summary> 
    /// <param name="fileName"></param> 
    /// <param name="bytesFrom"></param> 
    /// <param name="bytesToRead"></param> 
    /// <returns></returns> 
    private static byte[] ReadFile(string fileName, long bytesFrom, int bytesToRead) 
    { 
     using (FileStream fs = new FileStream(fileName, FileMode.Open)) 
     { 
      byte[] byteArray = new byte[bytesToRead]; 
      fs.Seek(bytesFrom, SeekOrigin.Begin); 
      fs.Read(byteArray, 0, bytesToRead); 
      return byteArray; 
     } 
    } 

    /// <summary> 
    /// This function uploads a block. 
    /// </summary> 
    /// <param name="baseUri"></param> 
    /// <param name="blockContents"></param> 
    /// <param name="blockId"></param> 
    /// <returns></returns> 
    private static bool UploadBlock(string baseUri, byte[] blockContents, string blockId) 
    { 
     bool isBlockUploaded = false; 
     //Create request URI - 
     string uploadBlockUri = string.Format("{0}&comp=block&blockId={1}", baseUri, Convert.ToBase64String(Encoding.UTF8.GetBytes(blockId))); 
     // Create request object 
     var request = (HttpWebRequest) HttpWebRequest.Create(uploadBlockUri); 
     NameValueCollection requestHeaders = new NameValueCollection(); 
     var requestDate = DateTime.UtcNow; 
     //Add request headers. Please note that since we're using SAS URI, we don't really need "Authorization" header. 
     requestHeaders.Add("x-ms-date", string.Format(CultureInfo.InvariantCulture, "{0:R}", requestDate)); 
     requestHeaders.Add("x-ms-version", x_ms_version); 
     request.Headers.Add(requestHeaders); 
     //Set content length header. 
     request.ContentLength = blockContents.Length; 
     //Set request HTTP method. 
     request.Method = "PUT"; 

     // Send the request 
     using (Stream requestStream = request.GetRequestStream()) 
     { 
      requestStream.Write(blockContents, 0, blockContents.Length); 
     } 
     // Get the response 
     using (var response = (HttpWebResponse)request.GetResponse()) 
     { 
      isBlockUploaded = response.StatusCode.Equals(HttpStatusCode.Created); 
     } 
     return isBlockUploaded; 
    } 

    /// <summary> 
    /// This function commits the block list. 
    /// </summary> 
    /// <param name="baseUri"></param> 
    /// <param name="blockIds"></param> 
    /// <returns></returns> 
    private static bool CommitBlockList(string baseUri, List<string> blockIds) 
    { 
     bool isBlockListCommitted = false; 
     //Create the request payload 
     StringBuilder blockIdsPayload = new StringBuilder(); 
     foreach (var blockId in blockIds) 
     { 
      blockIdsPayload.AppendFormat(blockIdTemplate, Convert.ToBase64String(Encoding.UTF8.GetBytes(blockId))); 
     } 
     string putBlockListPayload = string.Format(blockListTemplate, blockIdsPayload.ToString()); 
     // Create request URI 
     string putBlockListUrl = string.Format("{0}&comp=blocklist", baseUri); 
     // Create request object. 
     var request = (HttpWebRequest)HttpWebRequest.Create(putBlockListUrl); 
     NameValueCollection requestHeaders = new NameValueCollection(); 
     //Add request headers. Please note that since we're using SAS URI, we don't really need "Authorization" header. 
     var requestDate = DateTime.UtcNow; 
     requestHeaders.Add("x-ms-date", string.Format(CultureInfo.InvariantCulture, "{0:R}", requestDate)); 
     requestHeaders.Add("x-ms-version", x_ms_version); 
     byte[] requestPayload = Encoding.UTF8.GetBytes(putBlockListPayload); 
     //Set content length header. 
     request.ContentLength = requestPayload.Length; 
     request.Headers.Add(requestHeaders); 
     //Set request HTTP method. 
     request.Method = "PUT"; 

     // Send the request 
     using (Stream requestStream = request.GetRequestStream()) 
     { 
      requestStream.Write(requestPayload, 0, requestPayload.Length); 
     } 

     // Get the response 
     using (var response = (HttpWebResponse)request.GetResponse()) 
     { 
      isBlockListCommitted = response.StatusCode.Equals(HttpStatusCode.Created); 
     } 
     return isBlockListCommitted; 


    } 
} 

}

Answer 2

我相信你需要生成共享訪問簽名（SAS）URL。我對麼？當您生成SAS URL時，權限會在URI中進行編碼，因此您不必再使用授權密鑰。

爲了生成SAS，你會發現這兩個環節有用：

http://msdn.microsoft.com/en-us/library/windowsazure/hh508996

http://msdn.microsoft.com/en-us/library/windowsazure/ee395415

Answer 3

這是我最終的代碼（減去一些清理辦）的成功在仿真環境中測試：我用下面的代碼能夠在發展中存儲上傳的斑點。首先，客戶端代碼，它們是來自Microsoft REST API示例BlobHelper.cs的改編方法。然後是提供客戶端代碼使用的端點URL的服務器端代碼。再次感謝提示！ [R

// 
// Client side: The "Endpoint" used below is the Uri as returned from the Server-side code below. 
// 
// 
    public bool PutBlock(int blockId, string[] blockIds, byte[] value) 
    { 
     return Retry<bool>(delegate() 
     { 
      HttpWebResponse response; 

      try 
      { 
       SortedList<string, string> headers = new SortedList<string, string>(); 

       byte[] blockIdBytes = BitConverter.GetBytes(blockId); 
       string blockIdBase64 = Convert.ToBase64String(blockIdBytes); 

       blockIds[blockId] = blockIdBase64; 

       // SharedAccessKey version. 
       //End result will look similar to this in Fiddler if correct: 
       //PUT http://127.0.0.1:10000/devstoreaccount1/uploads/aecdfa39-7eaa-474a-9333-ecf43e6a0508?st=2012-08-17T16%3A11%3A53Z&se=2012-08-17T16%3A51%3A53Z&sr=b&sp=rw&sig=2%2Fs0R1L78S55pW5o2WontVvlZypjkTriWoljnycPbFc%3D&comp=block&blockid=AAAAAA== HTTP/1.1 
       // 
       response = CreateRESTRequestDirectUtf8("PUT", "&comp=block&blockid=" + blockIdBase64, value, headers).GetResponse() as HttpWebResponse; 

       response.Close(); 
       return true; 
      } 
      catch (WebException ex) 
      { 
       if (ex.Status == WebExceptionStatus.ProtocolError && 
        ex.Response != null && 
        (int)((HttpWebResponse)ex.Response).StatusCode == 409) 
        return false; 

       throw; 
      } 
     }); 
    } 

    ///<summary> 
    /// Put block list - complete creation of blob based on uploaded content. 
    /// </summary> 
    /// <param name="container">The container.</param> 
    /// <param name="blob">The BLOB.</param> 
    /// <param name="blockIds">The block ids.</param> 
    /// <returns></returns> 
    public bool PutBlockList(string[] blockIds) 
    { 
     return Retry<bool>(delegate() 
     { 
      HttpWebResponse response; 

      try 
      { 
       StringBuilder content = new StringBuilder(); 
       content.Append("<?xml version=\"1.0\" encoding=\"utf-8\"?>"); 
       content.Append("<BlockList>"); 
       for (int i = 0; i < blockIds.Length; i++) 
       { 
        content.Append("<Latest>" + blockIds[i] + "</Latest>"); 
       } 
       content.Append("</BlockList>"); 
       response = CreateRESTRequest("PUT", "&comp=blocklist", content.ToString(), null).GetResponse() as HttpWebResponse; 

       response.Close(); 
       return true; 
      } 
      catch (WebException ex) 
      { 
       if (ex.Status == WebExceptionStatus.ProtocolError && 
        ex.Response != null && 
        (int)(ex.Response as HttpWebResponse).StatusCode == 409) 
        return false; 

       throw; 
      } 
     }); 
    } 

    /// <summary> 
    /// Construct and issue a REST request and return the response. 
    /// </summary> 
    /// <param name="method">The method.</param> 
    /// <param name="resource">The resource.</param> 
    /// <param name="requestBody">The request body.</param> 
    /// <param name="headers">The headers.</param> 
    /// <param name="ifMatch">If match.</param> 
    /// <param name="md5">The MD5.</param> 
    /// <returns></returns> 
    public HttpWebRequest CreateRESTRequest(string method, string resource, string requestBody = null, SortedList<string, string> headers = null, 
     string ifMatch = "", string md5 = "") 
    { 
     byte[] byteArray = null; 
     DateTime now = DateTime.UtcNow; 
     Uri uri = new Uri(Endpoint + resource); 

     HttpWebRequest request = HttpWebRequest.Create(uri) as HttpWebRequest; 
     request.Method = method; 
     request.ContentLength = 0; 
     request.Headers.Add("x-ms-date", now.ToString("R", System.Globalization.CultureInfo.InvariantCulture)); 
     request.Headers.Add("x-ms-version", "2009-09-19"); //2009-09-19, 2011-08-18 

     if (IsTableStorage) 
     { 
      request.ContentType = "application/atom+xml"; 

      request.Headers.Add("DataServiceVersion", "1.0;NetFx"); 
      request.Headers.Add("MaxDataServiceVersion", "1.0;NetFx"); 
     } 

     if (headers != null) 
     { 
      foreach (KeyValuePair<string, string> header in headers) 
      { 
       request.Headers.Add(header.Key, header.Value); 
      } 
     } 

     if (!String.IsNullOrEmpty(requestBody)) 
     { 
      request.Headers.Add("Accept-Charset", "UTF-8"); 

      byteArray = Encoding.UTF8.GetBytes(requestBody); 
      request.ContentLength = byteArray.Length; 
     } 

     // We now get our SharedAccessKey from the server 
     //request.Headers.Add("Authorization", AuthorizationHeader(method, now, request, ifMatch, md5)); 

     if (!String.IsNullOrEmpty(requestBody)) 
     { 
      request.GetRequestStream().Write(byteArray, 0, byteArray.Length); 
     } 
     return request; 
    } 

    /// <summary> 
    /// Creates the REST request direct UTF8. 
    /// </summary> 
    /// <param name="method">The method.</param> 
    /// <param name="resource">The resource.</param> 
    /// <param name="requestBodyUtf8">The request body UTF8.</param> 
    /// <param name="headers">The headers.</param> 
    /// <param name="ifMatch">If match.</param> 
    /// <param name="md5">The MD5.</param> 
    /// <returns></returns> 
    private HttpWebRequest CreateRESTRequestDirectUtf8(string method, string resource, byte[] requestBodyUtf8, SortedList<string, string> headers = null, string ifMatch = "", string md5 = "") 
    { 
     //byte[] byteArray = null; 
     DateTime now = DateTime.UtcNow; 
     Uri uri = new Uri(Endpoint + resource); 

     HttpWebRequest request = HttpWebRequest.Create(uri) as HttpWebRequest; 
     request.Method = method; 
     request.ContentLength = 0; 
     request.Headers.Add("x-ms-date", now.ToString("R", System.Globalization.CultureInfo.InvariantCulture)); 
     request.Headers.Add("x-ms-version", "2009-09-19"); //2009-09-19, 2011-08-18 

     if (IsTableStorage) 
     { 
      request.ContentType = "application/atom+xml"; 

      request.Headers.Add("DataServiceVersion", "1.0;NetFx"); 
      request.Headers.Add("MaxDataServiceVersion", "1.0;NetFx"); 
     } 

     // Additional headers can be passed in as a formal parameter: 
     if (headers != null) 
     { 
      foreach (KeyValuePair<string, string> header in headers) 
      { 
       request.Headers.Add(header.Key, header.Value); 
      } 
     } 

     if (requestBodyUtf8 != null) 
     { 
      request.Headers.Add("Accept-Charset", "UTF-8"); 
      request.ContentLength = requestBodyUtf8.Length; 
     } 

     // We now get our SharedAccessKey from the server 
     //request.Headers.Add("Authorization", AuthorizationHeader(method, now, request, ifMatch, md5)); 

     if (requestBodyUtf8 != null) 
     { 
      request.GetRequestStream().Write(requestBodyUtf8, 0, requestBodyUtf8.Length); 
     } 

     return request; 
    } 

    // 
    // Server side: The returned Uri here is the "Endpoint" used in the client code. 
    // 
    /// <summary> 
    /// Gets the blob-level shared access signature for the named blob 
    /// </summary> 
    /// <param name="blobName">The unique blob name Guid.</param> 
    /// <returns>The fully qualified Azure Shared Access Signature Query String to be used in azure upload connections</returns> 
    public Uri GetBlobUploadUrl(Guid blobName) 
    { 
     string containerName = BlobContainerName; 
     const string permissions = "rw"; 
     string sharedAccessSignature = CreateSharedAccessSignature(containerName, blobName.ToString(), permissions); 

     string urlPath; 
     if (Microsoft.WindowsAzure.ServiceRuntime.RoleEnvironment.IsEmulated) 
     { // Emulation environment 
      urlPath = String.Format("{0}/{1}/{2}{3}", _blobEndpoint, containerName, blobName, sharedAccessSignature);    
     } 
     else 
     { // Cloud 
      urlPath = String.Format("{0}{1}/{2}{3}", _blobEndpoint, containerName, blobName, sharedAccessSignature); 
     } 

     Uri uri = new Uri(urlPath); 

     return uri; 
    } 

    /// <summary> 
    /// Creates a blob-level shared access signature. 
    /// </summary> 
    /// <param name="containerName">The blob container name.</param> 
    /// <param name="blobName">The blob name, a unique ID which will be passed back to the client.</param> 
    /// <param name="permissions">String of access levels, "r" = read, "w" = write "rw" = both etc.</param> 
    /// <returns>The fully qualified Azure Shared Access Signature Query String</returns> 
    private string CreateSharedAccessSignature(string containerName, string blobName, string permissions) 
    { 
     // SAS without stored container policy 
     const string iso8061Format = "{0:yyyy-MM-ddTHH:mm:ssZ}"; 
     DateTime startTime = DateTime.UtcNow.AddMinutes(-10d); //UtcNow; 
     DateTime expiryTime = startTime.AddMinutes(40d); 
     string start = string.Format(iso8061Format, startTime); 
     string expiry = string.Format(iso8061Format, expiryTime); 
     string stringToSign = string.Format("{0}\n{1}\n{2}\n/{3}/{4}/{5}\n", permissions, start, expiry, _accountName, containerName, blobName); 

     // SAS with stored container policy 
     //string stringToSign = String.Format("\n\n\n/{0}/{1}\n{2}", accountName, containerName, policyId); 

     string rawSignature = String.Empty; 
     Byte[] keyBytes = Convert.FromBase64String(_accountKey); 
     using (HMACSHA256 hmacSha256 = new HMACSHA256(keyBytes)) 
     { 
      Byte[] utf8EncodedStringToSign = System.Text.Encoding.UTF8.GetBytes(stringToSign); 
      Byte[] signatureBytes = hmacSha256.ComputeHash(utf8EncodedStringToSign); 
      rawSignature = Convert.ToBase64String(signatureBytes); 
     } 

     string sharedAccessSignature = String.Format("?st={0}&se={1}&sr=b&sp={2}&sig={3}", Uri.EscapeDataString(start), Uri.EscapeDataString(expiry), permissions, Uri.EscapeDataString(rawSignature)); 
     // 
     // End result will look like this in Fiddler if correct: 
     //PUT http://127.0.0.1:10000/devstoreaccount1/uploads/aecdfa39-7eaa-474a-9333-ecf43e6a0508?st=2012-08-17T16%3A11%3A53Z&se=2012-08-17T16%3A51%3A53Z&sr=b&sp=rw&sig=2%2Fs0R1L78S55uW5o2WontVvrZypckTriWoijnyrPbFc%3D&comp=block&blockid=AAAAAA== HTTP/1.1 
     // 
     return sharedAccessSignature; 
    }