为什么 Python Azure function 应用程序不将单个文件从存储帐户中的目录复制到目录？

Question

I have a Azure function app developed in Python which checks if any blobs available at a specific folder.
If blobs exists, loop through all blobs and copy them into another directory in the same storage account.
I have a code which is checking for file existence but loop is failing when only one single file is there in the container. Not sure why.

blob_service_client = BlobServiceClient.from_connection_string(os.getenv('AzureWebJobsStorage'))
container_ref = blob_service_client.get_container_client('container')
blobs = container_ref.list_blobs(name_starts_with='incoming/srcerx/')
blob_list = []
for s in blobs: #blobs have value of a blob, so loop starts
    blob_list.append(s)
    #use break to make sure only one iteration to avoid iterating all the blobs
    break
if len(blob_list) > 0: #length is 1 coming here
    fileCount = 0
    #move all blobs to dated directory in the same container
    for s in blobs: #not entering loop if only one blob is there
        print(s.name.replace('incoming/srcerx/',''))
        fileCount+=1
        moveBlobs(s.name)

I am not sure what wrong I am doing here. I tested this code with 1000 files, it copied all 999 files but left one.
It would be better if somebody suggest any better idea to load all blobs without loop in Python.

Answer 1

Use blow code:

from azure.storage.blob import BlobServiceClient, BlobClient, ContainerClient, __version__

connect_str = "DefaultEndpointsProtocol=https;AccountName=0730bowmanwindow;AccountKey=xxxxxx;EndpointSuffix=core.windows.net"
container_name = "test"

blob_service_client = BlobServiceClient.from_connection_string(connect_str)

container_name = "test"
container_client = blob_service_client.get_container_client(container_name)
blobs = container_client.list_blobs(name_starts_with="incoming/srcerx/")

num = 0

for blob in blobs:
    from_blobname = blob.name
    from_blob_client = blob_service_client.get_blob_client(container=container_name,blob=from_blobname)
    from_blob_url = from_blob_client.primary_endpoint

    file_name = from_blobname.replace("incoming/srcerx/","")
    to_blobname = "incoming/srcerx2/"+file_name
    to_blob_client = blob_service_client.get_blob_client(container=container_name,blob=to_blobname)
    to_blob_client.start_copy_from_url(from_blob_url)
    num = num + 1
    print(num)

Above code copy all of the files: