I have an application that upload, download and delete files on Azure blob storage. It works fine but when I perform load testing sometimes I got following exception during file download.
Microsoft.WindowsAzure.Storage.StorageException: The remote server returned an error: (404) Not Found. ---> System.Net.WebException: The remote server returned an error: (404) Not Found.
I am initializing these things once in constructor and then reuse it for all methods:
cloudStorageAccount = CloudStorageAccount.Parse(_storage.ConnectionString);
blobClient = cloudStorageAccount.CreateCloudBlobClient();
container = blobClient.GetContainerReference(_storage.Container);
var permission = container.GetPermissions();
permission.PublicAccess = BlobContainerPublicAccessType.Container;
container.SetPermissions(permission);
Here is my code for blob download:
MemoryStream memoryStream = new MemoryStream();
var retryPolicy = TransientFactory.GetStorageRetryPolicy();
retryPolicy.ExecuteAction(() =>
{
CloudBlockBlob blockBlob = container.GetBlockBlobReference(sourceUri);
if (blockBlob.Exists())
{
blockBlob.DownloadToStream(memoryStream);
memoryStream.Position = 0;
}
});
return memoryStream;
Make sure that the name of the file - which is a part of the URL - has EXACT same casing -
Do not use .ToLower() etc to change the casing.
Atleast this was the issue in my case.
Also check if the file is not uploaded to a sub Folder. In such case you'll need to add the name of this sub Folder in your Blob reference :
CloudBlockBlob blob = container.GetBlockBlobReference("subFolder/"+reference);
If you are using Azure Storage Client Library 4.0 or above, please pass in the blob name instead of a Uri to GetBlockBlobReference. Or if you would like to use a Uri, you should use the CloudBlockBlob constructor instead.
Related
I have another problem with Azure Blob Storage, this time with downloading. I get a list of files without a problem, unfortunately when I want to download it I get a 404 error that the file was not found.
using System.IO;
using System.Linq;
using Microsoft.WindowsAzure.Storage;
using Microsoft.WindowsAzure.Storage.Blob;
namespace BlobStorage
{
class Program
{
static void Main(string[] args)
{
CloudStorageAccount backupStorageAccount = CloudStorageAccount.Parse(
"{connectionString}");
var backupBlobClient = backupStorageAccount.CreateCloudBlobClient();
var backupContainer = backupBlobClient.GetContainerReference("{container-name");
var list = backupContainer.ListBlobs(useFlatBlobListing: true);
foreach (var blob in list)
{
var blobFileName = blob.Uri.Segments.Last();
CloudBlockBlob blockBlob = backupContainer.GetBlockBlobReference(blobFileName);
string destinationPath = string.Format(#"D:\" + blobFileName +".txt");
blockBlob.DownloadToFile(destinationPath, FileMode.OpenOrCreate);
}
}
}
}
Error message:
Microsoft.WindowsAzure.Storage.StorageException: "The remote server
returned an error: (404) Not found."
Internal exception WebException: The remote server returned an error:
(404) Not found.
And points to the line:
blockBlob.DownloadToFile (destinationPath, FileMode.OpenOrCreate);
A file like this most exists in blob storage. When I enter the blob editions, copy the url to a file, I can download it through the browser without any problem. Unfortunately, I can not download it from the application level due to a 404 error.
Only why does such a file exist?
The issue is how you're getting the blob name in the following line of code:
var blobFileName = blob.Uri.Segments.Last();
Considering, the path is tempdata/ExampleIotHub/02/2019/05/14/39, the blob's name is ExampleIotHub/02/2019/05/14/39 (assuming your container name is tempdata) however the blobFileName you're getting is just 39 (please see examples here). Since there is no blob by the name 39, you're getting this 404 error.
I suggest you try by doing something like the following:
foreach (var blob in list)
{
var localFileName = blob.Uri.Segments.Last();
CloudBlockBlob blockBlob = blob as CloudBlockBlob;
if (blockBlob != null)
{
string destinationPath = string.Format(#"D:\" + localFileName +".txt");
blockBlob.DownloadToFile(destinationPath, FileMode.OpenOrCreate);
}
}
Please note that I have not tried running this code so there may be some errors.
I've got some files sitting in an Azure File storage.
I'm trying to programatically archive them to Azure Blobs and I'm not sure how to do this efficiently.
I keep seeing code samples about copying from one blob container to another blob container .. but not from a File to a Blob.
Is it possible to do without downloading the entire File content locally and then uploading this content? Maybe use Uri's or something?
More Info:
The File and Blob containers are in the same Storage account.
The storage account is RA-GRS
Here was some sample code I was thinking of doing .. but it just doesn't feel right :( (pseudo code also .. with validation and checks omitted).
var file = await ShareRootDirectory.GetFileReference(fileName);
using (var stream = new MemoryStream())
{
await file.DownloadToStreamAsync(stream);
// Custom method that basically does:
// 1. GetBlockBlobReference
// 2. UploadFromStreamAsync
await cloudBlob.AddItemAsync("some-container", stream);
}
How to copy an Azure File to an Azure Blob?
We also can use CloudBlockBlob.StartCopy(CloudFile). CloudFile type is also can be accepted by the CloudBlockBlob.StartCopy function.
How to copy CloudFile to blob please refer to document. The following demo code is snippet from the document.
// Parse the connection string for the storage account.
CloudStorageAccount storageAccount = CloudStorageAccount.Parse(
Microsoft.Azure.CloudConfigurationManager.GetSetting("StorageConnectionString"));
// Create a CloudFileClient object for credentialed access to File storage.
CloudFileClient fileClient = storageAccount.CreateCloudFileClient();
// Create a new file share, if it does not already exist.
CloudFileShare share = fileClient.GetShareReference("sample-share");
share.CreateIfNotExists();
// Create a new file in the root directory.
CloudFile sourceFile = share.GetRootDirectoryReference().GetFileReference("sample-file.txt");
sourceFile.UploadText("A sample file in the root directory.");
// Get a reference to the blob to which the file will be copied.
CloudBlobClient blobClient = storageAccount.CreateCloudBlobClient();
CloudBlobContainer container = blobClient.GetContainerReference("sample-container");
container.CreateIfNotExists();
CloudBlockBlob destBlob = container.GetBlockBlobReference("sample-blob.txt");
// Create a SAS for the file that's valid for 24 hours.
// Note that when you are copying a file to a blob, or a blob to a file, you must use a SAS
// to authenticate access to the source object, even if you are copying within the same
// storage account.
string fileSas = sourceFile.GetSharedAccessSignature(new SharedAccessFilePolicy()
{
// Only read permissions are required for the source file.
Permissions = SharedAccessFilePermissions.Read,
SharedAccessExpiryTime = DateTime.UtcNow.AddHours(24)
});
// Construct the URI to the source file, including the SAS token.
Uri fileSasUri = new Uri(sourceFile.StorageUri.PrimaryUri.ToString() + fileSas);
// Copy the file to the blob.
destBlob.StartCopy(fileSasUri);
Note:
If you are copying a blob to a file, or a file to a blob, you must use a shared access signature (SAS) to authenticate the source object, even if you are copying within the same storage account.
Use the Transfer Manager:
https://msdn.microsoft.com/en-us/library/azure/microsoft.windowsazure.storage.datamovement.transfermanager_methods.aspx
There are methods to copy from CloudFile to CloudBlob.
Add the "Microsoft.Azure.Storage.DataMovement" nuget package
using Microsoft.WindowsAzure.Storage.Blob;
using Microsoft.WindowsAzure.Storage.File;
using Microsoft.WindowsAzure.Storage.DataMovement;
private string _storageConnectionString = "your_connection_string_here";
public async Task CopyFileToBlob(string blobContainer, string blobPath, string fileShare, string fileName)
{
CloudStorageAccount storageAccount = CloudStorageAccount.Parse(_connectionString);
CloudFileShare cloudFileShare = storageAccount.CreateCloudFileClient().GetShareReference(fileShare);
CloudFile source = cloudFileShare.GetRootDirectoryReference().GetFileReference(fileName);
CloudBlobContainer blobContainer = storageAccount.CreateCloudBlobClient().GetContainerReference(blobContainer);
CloudBlockBlob target = blobContainer.GetBlockBlobReference(blobPath);
await TransferManager.CopyAsync(source, target, true);
}
I've been trying to create a Windows Azure Blob containing an image file. I followed these tutorials: http://www.nickharris.net/2012/11/how-to-upload-an-image-to-windows-azure-storage-using-mobile-services/ and http://www.windowsazure.com/en-us/develop/mobile/tutorials/upload-images-to-storage-dotnet/. Finally the following code represents a merging of them. On the last line, however, an exception is raised:
An exception of type 'System.TypeLoadException' occurred in
mscorlib.ni.dll but was not handled in user code
Additional information: A binding for the specified type name was not
found. (Exception from HRESULT: 0x80132005)
Even the container is created the table, but It doesn't work properly.
private async void SendPicture()
{
StorageFile media = await StorageFile.GetFileFromPathAsync("fanny.jpg");
if (media != null)
{
//add todo item to trigger insert operation which returns item.SAS
var todoItem = new Imagem()
{
ContainerName = "mypics",
ResourceName = "Fanny",
ImageUri = "uri"
};
await imagemTable.InsertAsync(todoItem);
//Upload image direct to blob storage using SAS and the Storage Client library for Windows CTP
//Get a stream of the image just taken
using (var fileStream = await media.OpenStreamForReadAsync())
{
//Our credential for the upload is our SAS token
StorageCredentials cred = new StorageCredentials(todoItem.SasQueryString);
var imageUri = new Uri(todoItem.SasQueryString);
// Instantiate a Blob store container based on the info in the returned item.
CloudBlobContainer container = new CloudBlobContainer(
new Uri(string.Format("https://{0}/{1}",
imageUri.Host, todoItem.ContainerName)), cred);
// Upload the new image as a BLOB from the stream.
CloudBlockBlob blobFromSASCredential =
container.GetBlockBlobReference(todoItem.ResourceName);
await blobFromSASCredential.UploadFromStreamAsync(fileStream.AsInputStream());
}
}
}
Please use Assembly Binding Log Viewer to see which load is failing. As also mentioned in the article, the common language runtime's failure to locate an assembly typically shows up as a TypeLoadException in your application.
I am trying to rename blob in azure storage via .net API and it is I am unable to rename a blob file after a day : (
Here is how I am doing it, by creating new blob and copy from old one.
var newBlob = blobContainer.GetBlobReferenceFromServer(filename);
newBlob.StartCopyFromBlob(blob.Uri);
blob.Delete();
There is no new blob on server so I am getting http 404 Not Found exception.
Here is working example that i have found but it is for old .net Storage api.
CloudBlob blob = container.GetBlobReference(sourceBlobName);
CloudBlob newBlob = container.GetBlobReference(destBlobName);
newBlob.UploadByteArray(new byte[] { });
newBlob.CopyFromBlob(blob);
blob.Delete();
Currently I am using 2.0 API. Where I am I making a mistake?
I see that you're using GetBlobReferenceFromServer method to create an instance of new blob object. For this function to work, the blob must be present which will not be the case as you're trying to rename the blob.
What you could do is call GetBlobReferenceFromServer on the old blob, get it's type and then either create an instance of BlockBlob or PageBlob and perform copy operation on that. So your code would be something like:
CloudBlobContainer blobContainer = storageAccount.CreateCloudBlobClient().GetContainerReference("container");
var blob = blobContainer.GetBlobReferenceFromServer("oldblobname");
ICloudBlob newBlob = null;
if (blob is CloudBlockBlob)
{
newBlob = blobContainer.GetBlockBlobReference("newblobname");
}
else
{
newBlob = blobContainer.GetPageBlobReference("newblobname");
}
//Initiate blob copy
newBlob.StartCopyFromBlob(blob.Uri);
//Now wait in the loop for the copy operation to finish
while (true)
{
newBlob.FetchAttributes();
if (newBlob.CopyState.Status != CopyStatus.Pending)
{
break;
}
//Sleep for a second may be
System.Threading.Thread.Sleep(1000);
}
blob.Delete();
The code in OP was almost fine except that an async copy method was called. The simplest code in new API should be:
var oldBlob = cloudBlobClient.GetBlobReferenceFromServer(oldBlobUri);
var newBlob = container.GetBlobReference("newblobname");
newBlog.CopyFromBlob(oldBlob);
oldBlob.Delete();
I'm converting a website from a standard ASP.NET website over to use Azure. The website had previously taken an Excel file uploaded by an administrative user and saved it on the file system. As part of the migration, I'm saving this file to Azure Storage. It works fine when running against my local storage through the Azure SDK. (I'm using version 1.3 since I didn't want to upgrade during the development process.)
When I point the code to run against Azure Storage itself, though, the process usually fails. The error I get is:
System.IO.IOException occurred
Message=Unable to read data from the transport connection: The connection was closed.
Source=Microsoft.WindowsAzure.StorageClient
StackTrace:
at Microsoft.WindowsAzure.StorageClient.Tasks.Task`1.get_Result()
at Microsoft.WindowsAzure.StorageClient.Tasks.Task`1.ExecuteAndWait()
at Microsoft.WindowsAzure.StorageClient.CloudBlob.UploadFromStream(Stream source, BlobRequestOptions options)
at Framework.Common.AzureBlobInteraction.UploadToBlob(Stream stream, String BlobContainerName, String fileName, String contentType) in C:\Development\RateSolution2010\Framework.Common\AzureBlobInteraction.cs:line 95
InnerException:
The code is as follows:
public void UploadToBlob(Stream stream, string BlobContainerName, string fileName,
string contentType)
{
// Setup the connection to Windows Azure Storage
CloudStorageAccount storageAccount = CloudStorageAccount.Parse(GetConnStr());
DiagnosticMonitorConfiguration dmc = DiagnosticMonitor.GetDefaultInitialConfiguration();
dmc.Logs.ScheduledTransferPeriod = TimeSpan.FromMinutes(1);
dmc.Logs.ScheduledTransferLogLevelFilter = LogLevel.Verbose;
DiagnosticMonitor.Start(storageAccount, dmc);
CloudBlobClient BlobClient = null;
CloudBlobContainer BlobContainer = null;
BlobClient = storageAccount.CreateCloudBlobClient();
// For large file copies you need to set up a custom timeout period
// and using parallel settings appears to spread the copy across multiple threads
// if you have big bandwidth you can increase the thread number below
// because Azure accepts blobs broken into blocks in any order of arrival.
BlobClient.Timeout = new System.TimeSpan(1, 0, 0);
Role serviceRole = RoleEnvironment.Roles.Where(s => s.Value.Name == "OnlineRates.Web").First().Value;
BlobClient.ParallelOperationThreadCount = serviceRole.Instances.Count;
// Get and create the container
BlobContainer = BlobClient.GetContainerReference(BlobContainerName);
BlobContainer.CreateIfNotExist();
//delete prior version if one exists
BlobRequestOptions options = new BlobRequestOptions();
options.DeleteSnapshotsOption = DeleteSnapshotsOption.None;
CloudBlob blobToDelete = BlobContainer.GetBlobReference(fileName);
Trace.WriteLine("Blob " + fileName + " deleted to be replaced by newer version.");
blobToDelete.DeleteIfExists(options);
//set stream to starting position
stream.Position = 0;
long totalBytes = 0;
//Open the stream and read it back.
using (stream)
{
// Create the Blob and upload the file
CloudBlockBlob blob = BlobContainer.GetBlockBlobReference(fileName);
try
{
BlobClient.ResponseReceived += new EventHandler<ResponseReceivedEventArgs>((obj, responseReceivedEventArgs)
=>
{
if (responseReceivedEventArgs.RequestUri.ToString().Contains("comp=block&blockid"))
{
totalBytes += Int64.Parse(responseReceivedEventArgs.RequestHeaders["Content-Length"]);
}
});
blob.UploadFromStream(stream);
// Set the metadata into the blob
blob.Metadata["FileName"] = fileName;
blob.SetMetadata();
// Set the properties
blob.Properties.ContentType = contentType;
blob.SetProperties();
}
catch (Exception exc)
{
Logging.ExceptionLogger.LogEx(exc);
}
}
}
I've tried a number of different alterations to the code: deleting a blob before replacing it (although the problem exists on new blobs as well), setting container permissions, not setting permissions, etc.
Your code looks like it should work, but it has lots of extra functionality that is not strictly required. I would cut it down to an absolute minimum and go from there. It's really only a gut feeling, but I think it might be the using statement giving you grief. This enture function could be written (presuming the container already exists) as:
public void UploadToBlob(Stream stream, string BlobContainerName, string fileName,
string contentType)
{
// Setup the connection to Windows Azure Storage
CloudStorageAccount storageAccount = CloudStorageAccount.Parse(GetConnStr());
CloudBlobClient BlobClient = storageAccount.CreateCloudBlobClient();
CloudBlobContainer BlobContainer = BlobClient.GetContainerReference(BlobContainerName);
CloudBlockBlob blob = BlobContainer.GetBlockBlobReference(fileName);
stream.Position = 0;
blob.UploadFromStream(stream);
}
Notes on the stuff that I've removed:
You should set up diagnostics just once when you're app starts, not every time a method is called. Usually in the RoleEntryPoint.OnStart()
I'm not sure why you're trying to set ParallelOperationThreadCount higher if you have more instances. Those two things seem unrelated.
It's not good form to check for the existence of a container/table every time you save something to it. It's more usual to do that check once when your app starts or to have a process external to the website to make sure all the required containers/tables/queues exist. Of course if you're trying to dynamically create containers this is not true.
The problem turned out to be firewall settings on my laptop. It's my personal laptop originally set up at home and so the firewall rules weren't set up for a corporate environment resulting in slow performance on uploads and downloads.