4
votes

I have the following Azure function triggered when a file is uploaded to Blob Storage

[FunctionName("ImageAnalysis")]
    public static async void Run(
        [BlobTrigger("imageanalysis/{name}", Connection = "AzureWebJobsStorage")] Stream myBlob, 
        string name, 
        TraceWriter log)
    {
        log.Info($"C# Blob trigger function Processed blob\n Name:{name} \n Size: {myBlob.Length} Bytes");
    }

I want to process the Blob that has been uploaded so ideally I would like it as a CloudBlockBlob instead of a Stream. Then I can just do some work and then delete the blob.

myBlob.DeleteIfExists()

Is there an easy way to cast or convert my Stream to CloudBlockBlob or do I need to use input/output bindings or something else?

Looking through the docs I see examples which use CloudBlockBlob but I can't seem to get it to work so think I am missing something?

1
Please expand on "I can't seem to get it to work". CloudBlockBlob is supported.Mikhail Shilkov

1 Answers

8
votes

Use this syntax for the binding. The trick is specifying FileAccess.ReadWrite in the attribute. The docs rather confusingly refer to this as "inout" for some reason.

[Blob("imageanalysis/{name}", FileAccess.ReadWrite, Connection = "AzureWebJobsStorage")] CloudBlockBlob blob, string name