Blobs are accessible via REST calls, so you can actually manipulate blobs with a local desktop app if you wish, even written in PHP or Java.

As for webroles: each role is simply a virtual machine running on some server somewhere. Web roles are just like worker roles, with the addition of IIS. If you have a website, you can put the entire website in a single webrole. If you need to scale it to handle more users, you could create more than one "instance" of that webrole - and then all of your website s requests get sent to the various instances, each running the same code. (yes, you could have multiple webroles for a given app - this might be practical depending on your site s complexity, or if you have a completely different UI for administrators vs visitors).

You don t need to use a web role to access Azure Storage (Blob or otherwise). You can use a worker role, or you can even access it from a Windows Forms app running on a desktop, or a web/service app which isn t running on Azure.

See the Azure SDK s StorageClient documentation for info on how to access Azure Storage - it s pretty easy.

You don t need Azure project or other roles to use blob. If you want to use Azure client in .Net project, you can add your config to app settings section and reference it. Azure client is a wrapper to rest calls. They have some request signing steps which make the calls difficult to implement with simple webrequests.

 <add key="AzureBlobStorage" value="AccountName=youraccountname;AccountKey=YOURKEYeZgfgdfg==;DefaultEndpointsProtocol=https"/>

You can get the blob client:

 public CloudBlobClient GetBlobClient()
    {
        var accountBlob = ConfigurationManager.AppSettings["AzureBlobStorage"];

        var account = CloudStorageAccount.Parse(accountBlob.ToString());


        return account.CreateCloudBlobClient();

    }


public CloudBlob GetBlob(BlobItem blobItem)
        {
            var client = GetBlobClient();
            var cloudBlobContainer = client.GetContainerReference(blobItem.ContainerReference);
            return cloudBlobContainer.GetBlobReference(blobItem.FileName);
        }

BlobItem is just a wrapper. Basically, you need folder name and filename to access a blob.

 public class BlobItem
{
    [Required]
    [Display(Name = "Container")]
    public string ContainerReference { get; set; }
    [Required]
    [Display(Name = "File name")]
    public string FileName { get; set; }

    [Required]
    [UIHint("MultilineText")]
    public string Content { get; set; }

    /// <summary>
    /// to use in stream mode
    /// </summary>
    public Stream Stream { get; set; }
}