Azure storage - Any timing issues with this code? - azure

Question

I am using Azure storage to store and retrieve images. I have this method to save an image (blob):
public void SaveBlob(string containerName, string blobName, byte[] blob)
{
// Retrieve reference to the blob
CloudBlockBlob blockBlob = GetContainer(containerName, true).GetBlockBlobReference(blobName);
using (var stream = new MemoryStream(blob, writable: false))
{
blockBlob.UploadFromStream(stream);
}
}
This is the GetContainer method:
public CloudBlobContainer GetContainer(string containerName, bool createIfNotExist)
{
if (string.IsNullOrEmpty(containerName))
return null;
// Retrieve a reference to a container. If container doesn't exist, optionally create it.
CloudBlobContainer container = this._blobClient.GetContainerReference(containerName);
if (container == null && !createIfNotExist)
return null;
// Create the container if it doesn't already exist. It will be private by default.
container.CreateIfNotExists(BlobContainerPublicAccessType.Off, null, null);
return container;
}
What's happening here is that when I attempt to save a blob, I get a reference to a container first. If the container doesn't exist, it is created, and then the blob is saved. Will I run into timing issues here if I have to create the container first and then save a blob to it immediately? My concern is that I might be attempting to save the blob to the container before Azure is finished creating it. Or maybe this isn't an issue?

Answer 1

Looking at your code, I don't think you will run into any timing issues because CreateIfNotExists method is a sync method and will only return when the container is created. Also with Azure Blob Storage (unlike Amazon S3), the method will either create the container immediately or throw an error if it fails to do so (or in other words Azure Storage is Strongly Consistent).
Also I think this piece of code is redundant:
if (container == null && !createIfNotExist)
return null;
As container will never be equal to null and thus this if condition will never be true.