How to retrieve blobs within a blob directory path using the Azure.Storage.Blobs BlobClient?

Question

I'm not seeing any examples online on how to get all the blobs located inside a certain directory within a BlobContainerClient.

Previously, I was using the Microsoft.Azure.Storage packages, but those have since been deprecated. My old code that was scanning a directory for all blobs was:

public async Task<void> ListAllBlobs(string path)
{
    var myContainer = await GetCloudBlobClientAsync();
    var directory = myContainer.GetDirectoryReference(path);
    var blobs = await directory.ListBlobsSegmentedAsync(true, BlobListingDetails.None, 
        blobSettings.MaxResult, null, null, null);
    var results = blobs.Results;

    foreach(CloudBlockBlob b in results)
    {
        // non-relevant code
    }
}

private async Task<CloudBlobContainer> GetCloudBlobClientAsync()
{
    var storageAccount = CloudStorageAccount.Parse(azureBlobStorageConnectionString);
    var blobClient = storageAccount.CreateCloudBlobClient();
    var container = blobClient.GetContainerReference(blobStorageSettings.ContainerName);

    if (!await container.ExistsAsync())
    {
        await container.CreateAsync();
    }

    return container;
}

Essentially, I'm moving the above code from Microsoft.Azure.Storage over to Azure.Storage.Blobs.

If I were to recreate the ListAllBlobs(string path) function to use Azure.Storage.Blobs, I'm confused on how to setup a container and then access an inner container based on a path that's passed in - then cycle through the blobs that exist within that container. Can anyone help?

Here's what I have so far:

public async Task<void> ListAllBlobs(string path)
{
    var myContainer = await GetCloudBlobClientAsync();
    var directory = myContainer.GetBlobClient(path);

    // This doesn't work because I can't do 'GetBlobs' on the Client, only on the container.
    foreach(BlobItem blob in directory.GetBlobs(Blobtraits.None, BlobStates.None, string.Empty))
    {
        // more non-relevant code
    }
}

To clarify, in the above code, it doesn't like that I'm calling GetBlobs on a Client, rather than on the Container, but I can't pass in a path to the container.

Answer 1

You were almost there. You would still use BlobContainerClient and call GetBlobsAsync method on that. What you missed is that you will need to set the prefix parameter's value as the path.

So your code would be something like:

var myContainer = await GetCloudBlobClientAsync();
var blobsListingResult = await myContainer.GetBlobsAsync(prefix=path);

UPDATE

Please try the following code:

var myContainer = await GetCloudBlobClientAsync();
await foreach (BlobItem blob in myContainer.GetBlobsAsync(BlobTraits.None, BlobStates.None, path))
{
  names.Add(blob.Name);
}