Azure Storage Blob Rename

Question

Is is possible to rename an Azure Storage Blob using the Azure Storage API from a Web Role? The only solution I have at the moment is to copy the blob to a new blob with the correct name and delete the old one.

Answer 1

There is practical way to do so, although Azure Blob Service API does not directly support ability to rename or move blobs.

Answer 2

UPDATE:

I updated the code after @IsaacAbrahams comments and @Viggity's answer, this version should prevent you from having to load everything into a MemoryStream, and waits until the copy is completed before deleting the source blob.

---

For anyone getting late to the party but stumbling on this post using Azure Storage API V2, here's an extension method to do it quick and dirty (+ async version):

public static class BlobContainerExtensions 
{
   public static void Rename(this CloudBlobContainer container, string oldName, string newName)
   {
      //Warning: this Wait() is bad practice and can cause deadlock issues when used from ASP.NET applications
      RenameAsync(container, oldName, newName).Wait();
   }

   public static async Task RenameAsync(this CloudBlobContainer container, string oldName, string newName)
   {
      var source = await container.GetBlobReferenceFromServerAsync(oldName);
      var target = container.GetBlockBlobReference(newName);

      await target.StartCopyFromBlobAsync(source.Uri);

      while (target.CopyState.Status == CopyStatus.Pending)
            await Task.Delay(100);

      if (target.CopyState.Status != CopyStatus.Success)
          throw new Exception("Rename failed: " + target.CopyState.Status);

      await source.DeleteAsync();
    }
}

Update for Azure Storage 7.0

    public static async Task RenameAsync(this CloudBlobContainer container, string oldName, string newName)
    {
        CloudBlockBlob source =(CloudBlockBlob)await container.GetBlobReferenceFromServerAsync(oldName);
        CloudBlockBlob target = container.GetBlockBlobReference(newName);


        await target.StartCopyAsync(source);

        while (target.CopyState.Status == CopyStatus.Pending)
            await Task.Delay(100);

        if (target.CopyState.Status != CopyStatus.Success)
            throw new Exception("Rename failed: " + target.CopyState.Status);

        await source.DeleteAsync();            
    }

Disclaimer: This is a quick and dirty method to make the rename execute in a synchronous way. It fits my purposes, however as other users noted, copying can take a long time (up to days), so the best way is NOT to perform this in 1 method like this answer but instead:

• Start the copy process
• Poll the status of the copy operation
• Delete the original blob when the copy is completed.

Answer 3

You can, however, copy and then delete.

Answer 4

I originally used code from @Zidad, and in low load circumstances it usually worked (I'm almost always renaming small files, ~10kb).

DO NOT StartCopyFromBlob then Delete!!!!!!!!!!!!!!

In a high load scenario, I LOST ~20% of the files I was renaming (thousands of files). As mentioned in the comments on his answer, StartCopyFromBlob just starts the copy. There is no way for you to wait for the copy to finish.

The only way for you to guarantee the copy finishes is to download it and re-upload. Here is my updated code:

public void Rename(string containerName, string oldFilename, string newFilename)
{
    var oldBlob = GetBlobReference(containerName, oldFilename);
    var newBlob = GetBlobReference(containerName, newFilename);

    using (var stream = new MemoryStream())
    {
        oldBlob.DownloadToStream(stream);
        stream.Seek(0, SeekOrigin.Begin);
        newBlob.UploadFromStream(stream);

        //copy metadata here if you need it too

        oldBlob.Delete();
    }
}

Answer 5

While this is an old post, perhaps this excellent blog post will show others how to very quickly rename blobs that have been uploaded.

Here are the highlights:

//set the azure container
string blobContainer = "myContainer";
//azure connection string
string dataCenterSettingKey = string.Format("DefaultEndpointsProtocol=https;AccountName={0};AccountKey={1}", "xxxx",
                                            "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx");
//setup the container object
CloudStorageAccount cloudStorageAccount = CloudStorageAccount.Parse(dataCenterSettingKey);
CloudBlobClient blobClient = cloudStorageAccount.CreateCloudBlobClient();
CloudBlobContainer container = blobClient.GetContainerReference(blobContainer);

// Set permissions on the container.
BlobContainerPermissions permissions = new BlobContainerPermissions();
permissions.PublicAccess = BlobContainerPublicAccessType.Blob;
container.SetPermissions(permissions);

//grab the blob
CloudBlob existBlob = container.GetBlobReference("myBlobName");
CloudBlob newBlob = container.GetBlobReference("myNewBlobName");
//create a new blob
newBlob.CopyFromBlob(existBlob);
//delete the old
existBlob.Delete();

Answer 6

Copy the blob, then delete it.

Tested for files of 1G size, and it works OK.

For more information, see the sample on MSDN.

StorageCredentials cred = new StorageCredentials("[Your?storage?account?name]", "[Your?storage?account?key]");  
CloudBlobContainer container = new CloudBlobContainer(new Uri("http://[Your?storage?account?name].blob.core.windows.net/[Your container name] /"), cred);  

string fileName = "OldFileName";  
string newFileName = "NewFileName";  
await container.CreateIfNotExistsAsync();  

CloudBlockBlob blobCopy = container.GetBlockBlobReference(newFileName);  

if (!await blobCopy.ExistsAsync())  
{  
    CloudBlockBlob blob = container.GetBlockBlobReference(fileName);  

    if (await blob.ExistsAsync())  
    {  
           // copy
           await blobCopy.StartCopyAsync(blob);                               
           // then delete
           await blob.DeleteIfExistsAsync();  
    } 
} 

Answer 7

Using Monza Cloud's Azure Explorer, I can rename an 18 Gigabyte blob in under a second. Microsoft's Azure Storage Explorer takes 29 sec to clone that same blob, so Monza is not doing a copy. I know it is fast because immediately after the Monza rename, clicking the container in Microsoft Azure Storage Explorer shows the blob with the new name.

Answer 8

The only way at the mement is to move the src blob to a new destination/name. Here is my code to do this

 public async Task<CloudBlockBlob> RenameAsync(CloudBlockBlob srcBlob, CloudBlobContainer destContainer,string name)
    {
        CloudBlockBlob destBlob;

        if (srcBlob == null && srcBlob.Exists())
        {
            throw new Exception("Source blob cannot be null and should exist.");
        }

        if (!destContainer.Exists())
        {
            throw new Exception("Destination container does not exist.");
        }

        //Copy source blob to destination container            
        destBlob = destContainer.GetBlockBlobReference(name);
        await destBlob.StartCopyAsync(srcBlob);
        //remove source blob after copy is done.
        srcBlob.Delete();
        return destBlob;
    }

Here is a code sample if you want the blob lookup as part of the method:

    public CloudBlockBlob RenameBlob(string oldName, string newName, CloudBlobContainer container)
    {
        if (!container.Exists())
        {
            throw new Exception("Destination container does not exist.");
        }
        //Get blob reference
        CloudBlockBlob sourceBlob = container.GetBlockBlobReference(oldName);

        if (sourceBlob == null && sourceBlob.Exists())
        {
            throw new Exception("Source blob cannot be null and should exist.");
        }

        // Get blob reference to which the new blob must be copied
        CloudBlockBlob destBlob = container.GetBlockBlobReference(newName);
        destBlob.StartCopyAsync(sourceBlob);

        //Delete source blob
        sourceBlob.Delete();
        return destBlob;
    }

Answer 9

You can now with the new release in public preview of ADLS Gen 2 ( Azure Data Lake Storage Gen 2)

The Hierarchical Namespace capability allows you to perform atomic manipulation of directories and files which includes Rename operation.

However, make note of the following: "With the preview release, if you enable the hierarchical namespace, there is no interoperability of data or operations between Blob and Data Lake Storage Gen2 REST APIs. This functionality will be added during preview."

You will need to make sure you create the blobs (files ) using ADLS Gen 2 to rename them. Otherwise, wait for the interoperability between Blob APIs and ADLS Gen 2 to be added during the preview time period.

Answer 10

There is also a way without copying your blob to rename it, and without running any script: mounting Azure Blob storage to your OS: https://docs.microsoft.com/bs-latn-ba/azure/storage/blobs/storage-how-to-mount-container-linux

Then you can just use mv and your blob will be renamed instantly.

Answer 11

Using Azure Storage Explorer is the easiest way to manually rename a blob. You can download it here https://azure.microsoft.com/en-us/features/storage-explorer/#overview

Answer 12

This worked for me in live environment of 100K Users having file sizes no more than 100 mb. This is similar synchronous approach to @viggity's answer. But the difference is that its copying everything on Azure side so you don't have to hold Memorystream on your server for Copy/Upload to new Blob.

 var account = new CloudStorageAccount(new Microsoft.WindowsAzure.Storage.Auth.StorageCredentials(StorageAccountName, StorageAccountKey), true);
 CloudBlobClient blobStorage = account.CreateCloudBlobClient();
 CloudBlobContainer container = blobStorage.GetContainerReference("myBlobContainer");

 string fileName = "OldFileName";  
 string newFileName = "NewFileName"; 

 CloudBlockBlob oldBlob = container.GetBlockBlobReference(fileName);
 CloudBlockBlob newBlob = container.GetBlockBlobReference(newFileName);
 using (var stream = new MemoryStream())
 {
      newBlob.StartCopyFromBlob(oldBlob);
      do { } while (!newBlob.Exists());
      oldBlob.Delete();
 }

Answer 13

If you set the ContentDisposition property with

attachment;filename="yourfile.txt"

The name of the download over http will be whatever you want.

I think Storage was built with the assumption that data would be stored in a way with unique identifiers primarily used as the filenames. Issuing Shared Access Signatures for all downloads is a bit weird though, so this isn't ideal for some people.

But I think abstracting away the user-facing filename is overall a good practice and encourages a more stable architecture overall.