尝试在Web API请求上检索Azure Blob时出现403错误 [英] Getting 403 error when trying to retrieve an Azure blob on Web API request
问题描述
我正在尝试通过JWT进行身份验证的GET请求返回存储在Azure blob中的图像.当我在本地计算机上运行项目并使用邮递员请求图像时，请求通过，并且我确实获得了所请求的图像.但是，将代码部署到Azure并命中相同的端点后，我得到403.代码在尝试调用DownloadToStreamAsync的行失败.这是我正在使用的代码:
I am trying to have an authenticated (by JWT) GET request return an image stored in an Azure blob. When I run the project on my local machine and use postman to request an image and the request goes through and I do get the image I requested. However, once I deploy the code to Azure and hit the same endpoint I get a 403. The code fails at the line in which I try to invoke DownloadToStreamAsync. Here is the code I'm using:
public async Task<BlobDownloadModel> DownloadBlob(Guid blobId)
{
try
{
//get picture record
Picture file = await _media.GetPictureAsync(blobId);
await _log.CreateLogEntryAsync("got picture record");
// get string format blob name
var blobName = file.PictureId.ToString() + file.Extension;
await _log.CreateLogEntryAsync("got name of blob " + blobName);
if (!String.IsNullOrEmpty(blobName))
{
await _log.CreateLogEntryAsync("blob not empty");
var blob = _container.GetBlockBlobReference(blobName);
await _log.CreateLogEntryAsync("got blob: " + blob.ToString());
var ms = new MemoryStream();
await blob.DownloadToStreamAsync(ms);
await _log.CreateLogEntryAsync("blob downloaded to memory stream");
var lastPos = blob.Name.LastIndexOf('/');
var fileName = blob.Name.Substring(lastPos + 1, blob.Name.Length - lastPos - 1);
var download = new BlobDownloadModel
{
BlobStream = ms,
BlobFileName = fileName,
BlobLength = blob.Properties.Length,
BlobContentType = blob.Properties.ContentType
};
return download;
}
}
catch(Exception ex)
{
await _log.CreateLogEntryAsync("exception thrown: " + ex.ToString());
}
我将非常感谢我能提供的任何帮助.
I would greatly appreciate any help I can get.
更新:
我将代码更改为此，然后再次尝试:
I changed my code to this and tried again:
public async Task<AzureBlobModel> DownloadBlob(Guid blobId)
{
try
{
//get picture record
Picture file = await _media.GetPictureAsync(blobId);
await _log.CreateLogEntryAsync("got picture record");
// get string format blob name
var blobName = file.PictureId.ToString() + file.Extension;
await _log.CreateLogEntryAsync("got name of blob " + blobName);
if (!String.IsNullOrEmpty(blobName))
{
await _log.CreateLogEntryAsync("blob not empty");
var blob = _container.GetBlockBlobReference(blobName);
await _log.CreateLogEntryAsync("got blob: " + blob.ToString());
// Strip off any folder structure so the file name is just the file name
var lastPos = blob.Name.LastIndexOf('/');
var fileName = blob.Name.Substring(lastPos + 1, blob.Name.Length - lastPos - 1);
await _log.CreateLogEntryAsync("got fileName: " + fileName);
//await blob.DownloadToStreamAsync(ms);
await _log.CreateLogEntryAsync("about to open read stream");
var stream = await blob.OpenReadAsync();
await _log.CreateLogEntryAsync("opened read stream");
var result = new AzureBlobModel()
{
FileName = fileName,
FileSize = blob.Properties.Length,
Stream = stream,
ContentType = blob.Properties.ContentType
};
await _log.CreateLogEntryAsync("blob downloaded to memory stream");
return result;
// Build and return the download model with the blob stream and its relevant info
//var download = new BlobDownloadModel
//{
// BlobStream = ms,
// BlobFileName = fileName,
// BlobLength = blob.Properties.Length,
// BlobContentType = blob.Properties.ContentType
//};
//return download;
}
}
catch(Exception ex)
{
await _log.CreateLogEntryAsync("exception thrown: " + ex.ToString());
}
await _log.CreateLogEntryAsync("returning null");
// Otherwise
return null;
}
上次尝试的日志结果如下:
the results from the log for the last try is this:
已收到请求并进行了身份验证，时间戳为UTC时间戳:2017年3月10日5:28:26 AM-5:28:26 AM
收到的ID:b3bc7faf-0c86-4ce2-af84-30636825a485-5:28:27 AM
得到了图片记录-5:28:27 AM
获得了blob b3bc7faf-0c86-4ce2-af84-30636825a485.JPG-5:28:27 AM
的名称
Blob不为空-上午5:28:27
有Blob:Microsoft.WindowsAzure.Storage.Blob.CloudBlockBlob-5:28:27 AM
得到的文件名:b3bc7faf-0c86-4ce2-af84-30636825a485.JPG-5:28:27 AM
即将打开阅读流-上午5:28:27
request received and authenticated, timestamp UTC: 3/10/2017 5:28:26 AM - 5:28:26 AM
id received: b3bc7faf-0c86-4ce2-af84-30636825a485 - 5:28:27 AM
got picture record -5:28:27 AM
got name of blob b3bc7faf-0c86-4ce2-af84-30636825a485.JPG - 5:28:27 AM
blob not empty - 5:28:27 AM
got blob: Microsoft.WindowsAzure.Storage.Blob.CloudBlockBlob - 5:28:27 AM
got fileName: b3bc7faf-0c86-4ce2-af84-30636825a485.JPG - 5:28:27 AM
about to open read stream - 5:28:27 AM
我能够检索文件/blob的名称，从而消除了不正确的帐户密钥作为问题的根源.
I was able to retrieve the name of the file/blob which eliminates an incorrect account key as the culprit of the issue.
解决方案
我能够使我的代码与以下代码一起使用:
I was able to get my code to work with the following code:
public async Task<AzureBlobModel> DownloadBlob(Guid blobId)
{
try
{
//get picture record
Picture file = await _media.GetPictureAsync(blobId);
// get string format blob name
var blobName = file.PictureId.ToString() + file.Extension;
if (!String.IsNullOrEmpty(blobName))
{
var blob = _container.GetBlockBlobReference(blobName);
// Strip off any folder structure so the file name is just the file name
var lastPos = blob.Name.LastIndexOf('/');
var fileName = blob.Name.Substring(lastPos + 1, blob.Name.Length - lastPos - 1);
var fileLength = blob.Properties.Length;
var stream = await blob.OpenReadAsync();
var result = new AzureBlobModel()
{
FileName = fileName,
FileSize = blob.Properties.Length,
Stream = stream,
ContentType = blob.Properties.ContentType
};
return result;
}
}
catch(Exception ex)
{
await _log.CreateLogEntryAsync("exception thrown: " + ex.ToString());
}
await _log.CreateLogEntryAsync("returning null");
// Otherwise
return null;
}
推荐答案
我能够通过使用以下代码解决问题:
I was able to solve the problem by using the following code:
public async Task<AzureBlobModel> DownloadBlob(Guid blobId)
{
try
{
//get picture record
Picture file = await _media.GetPictureAsync(blobId);
// get string format blob name
var blobName = file.PictureId.ToString() + file.Extension;
if (!String.IsNullOrEmpty(blobName))
{
var blob = _container.GetBlockBlobReference(blobName);
// Strip off any folder structure so the file name is just the file name
var lastPos = blob.Name.LastIndexOf('/');
var fileName = blob.Name.Substring(lastPos + 1, blob.Name.Length - lastPos - 1);
var fileLength = blob.Properties.Length;
var stream = await blob.OpenReadAsync();
var result = new AzureBlobModel()
{
FileName = fileName,
FileSize = blob.Properties.Length,
Stream = stream,
ContentType = blob.Properties.ContentType
};
return result;
}
}
catch(Exception ex)
{
await _log.CreateLogEntryAsync("exception thrown: " + ex.ToString());
}
await _log.CreateLogEntryAsync("returning null");
// Otherwise
return null;
}
这篇关于尝试在Web API请求上检索Azure Blob时出现403错误的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
