Using Azure StorageClient, I want to Get list of "Directories" and "Files" in given container

Question

I've been looking through lots of articles (so please don't post links to them) regarding how to get a list of blob inside a given container.  I want to be able to separate "directory" type blob's from non-directory.  That is, if a blob container has 4 flies in it:

https://....blob.core.windows.net/3-6469723158585858/newa.txt

https://....blob.core.windows.net/3-6469723158585858/TopDir1

https://....blob.core.windows.net/3-6469723158585858/TopDir1/filea.txt

https://....blob.core.windows.net/3-6469723158585858/TopDir1/fileb.txt

I want to be able to first, get a list that just contains the one directory name (...TopDir1), then, using that name, get a list of the two files inside it (..TopDir1/filea.txt and ../TopDir1/fileb.txt

Thanks for any help on this.

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Peter Kellner http://peterkellner.net Microsoft MVP • ASPInsider

Answer 1

If you're saying you want to get just the directory (and not the blobs at the same level), I don't think there's a way to do this.  (You can filter it client-side, but not on the server.)

You can do the second half, though, by listing blobs with the prefix TopDir1.

Answer 2

how would I filter it on the client side?  (that is where I actually want to filter it).  I know the azure blob explorers all do this because they manage to present me with view that shows the directory structure.  I'm must trying to do the same thing.

 

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Peter Kellner http://peterkellner.net Microsoft MVP • ASPInsider

Answer 3

The following code appears to do something close to what you want. It gets a top-level directory and then iterates over the names in the subdirectory:

protected void GetDirectoryList(String topLevelDirectoryName, String subDirectoryName)
{
  CloudStorageAccount cloudStorageAccount =
    CloudStorageAccount.FromConfigurationSetting("DataConnectionString");
  CloudBlobClient cloudBlobClient = cloudStorageAccount.CreateCloudBlobClient(); 

  CloudBlobDirectory topLevelDirectory = cloudBlobClient.GetBlobDirectoryReferencetopLevelDirectoryName); 

  CloudBlobDirectory subDirectory = topLevelDirectory.GetSubdirectory(subDirectoryName); 

  IEnumerable<IListBlobItem> blobItems = subDirectory.ListBlobs();
  foreach (IListBlobItem blobItem in blobItems)
  {
    Uri uri = blobItem.Uri;
  }
}

Answer 4

I'm still not getting it.  I tried the code above (with the changes I think I'm expected to make) and it does not give me a result (no blobItems).  I tried with no slash, front and back also.

Also, I don't know the name of the subdirectory ("mydir1").  That is what I need to iterate for, even if the example did work, it does not give me a hint on how to get that name.

private void buttonListContainer_Click(object sender, EventArgs e)
    {
      CloudBlobClient cloudBlobClient = _storageAccount.CreateCloudBlobClient();
      CloudBlobDirectory topLevelDirectory =
        cloudBlobClient.GetBlobDirectoryReference(
          "https://peterstest.blob.core.windows.net/3-6469723158585858?restype=container&comp=list");
      
      CloudBlobDirectory subDirectory = topLevelDirectory.GetSubdirectory("/mydir1");

      IEnumerable<IListBlobItem> blobItems = subDirectory.ListBlobs();
      foreach (IListBlobItem blobItem in blobItems)
      {
        Uri uri = blobItem.Uri;
      }

 

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Peter Kellner http://peterkellner.net Microsoft MVP • ASPInsider

Answer 5

Note: I did take out the extra stuff after the url: ?restype=container&comp=list");

and it did give me a list. 

I still don't know how to get the top level (that is not "mydir1"), and how to tell if the files are directories.  That is, when I look in the debugger at the property of blobItem, it shows isFile = false whether or not it is the directory entry.

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Peter Kellner http://peterkellner.net Microsoft MVP • ASPInsider

Answer 6

Continuing down this path, is the only way to tell if a blog is a "directory" is to see if it ends in a "/"?  Does that mean that blobnames that end in "/" are always directory entries, or could that confuse me on a file that was not really a directory.

when I try to make a filename end in /, windows screams at me.

 

Here is some modified code I'm messing around with to do this.

      CloudBlobClient cloudBlobClient = _storageAccount.CreateCloudBlobClient();

      CloudBlobDirectory topLevelDirectory =
        cloudBlobClient.GetBlobDirectoryReference(
          "https://peterstest.blob.core.windows.net/3-6469723158585858");


      IEnumerable<IListBlobItem> blobItemsTop = topLevelDirectory.ListBlobs();
      foreach (IListBlobItem blobItem in blobItemsTop)
      {
        Uri uri = blobItem.Uri;
      }

      CloudBlobDirectory subDirectory = topLevelDirectory.GetSubdirectory("mydir1");
      IEnumerable<IListBlobItem> blobItems = subDirectory.ListBlobs();
      foreach (IListBlobItem blobItem in blobItems)
      {
        Uri uri = blobItem.Uri;
      }

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Peter Kellner http://peterkellner.net Microsoft MVP • ASPInsider

Answer 7

IListBlobItem is the base class for CloudBlobDirectory, CloudBlockBlob, CloudBlockBlob and CloudPageBlob. You should be able to identify whether a particular item is a blob or a directory by just looking at its actual type.

Answer 8

Try this code.  Basically, the thing to do is check the type on each of the IListBlobItems returned:

var blobs = CloudStorageAccount.DevelopmentStorageAccount.CreateCloudBlobClient();
var container = blobs.GetContainerReference("testcontainer");
container.CreateIfNotExist();
container.GetBlobReference("directory/blob.txt").UploadText(string.Empty);
container.GetBlobReference("blob.txt").UploadText(string.Empty);

var items = container.ListBlobs();

Console.WriteLine("Directories:");
foreach (var dir in items.OfType<CloudBlobDirectory>())
{
  Console.WriteLine("\t{0}", dir.Uri);
}

Console.WriteLine("Blobs:");
foreach (var blob in items.OfType<CloudBlob>())
{
  Console.WriteLine("\t{0}", blob.Uri);
}

Answer 9

Just so I have a good example (and understanding) for myself, I did a short blob post and included code for a simple windows form c# app that let's you view your blob storage as a directory tree.

http://peterkellner.net/2010/11/12/azure-storage-treeviewer-directory-browser/

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Peter Kellner http://peterkellner.net Microsoft MVP • ASPInsider