Can you set metadata on an Azure CloudBlockBlob at the same time as uploading it?

Question

I have a situation in which I currently upload a CloudBlockBlob using :

CloudBlockBlob.UploadFromStreamAsync

and then immediately afterward I set a bunch of user metadata on it.

The issue is: I have an Event Grid event which is triggered when the blob is uploaded, but the event handler requires the metadata. Long story short, it's a race condition wherein I have to "hope" that the metadata has been set before my event handler responds to the block blob upload.

Is there some way to both upload the block blob (file) and set its metadata in a single operation?

Answer 1

As juunas said, you could just set the metadata on the blob before calling Upload. I make a little demo with .Net Console you could refer to.

public static void Main(string[] args)
{
    CloudStorageAccount storageAccount = CloudStorageAccount.Parse(CloudConfigurationManager.GetSetting("StorageConnectionString"));
    CloudBlobClient cloudBlobClient = storageAccount.CreateCloudBlobClient();
    CloudBlobContainer container = cloudBlobClient.GetContainerReference("container");
    CloudBlockBlob cloudBlockBlob = container.GetBlockBlobReference("hello.txt");
    MemoryStream msWrite = new MemoryStream(Encoding.UTF8.GetBytes("aaaaaa"));
    msWrite.Position = 0;
    cloudBlockBlob.Metadata["category"] = "guidance";
    using (msWrite)
    {
        cloudBlockBlob.UploadFromStream(msWrite);
    }
 }

The output in blob on portal: