Create file system/container if not found

Question

I'm trying to export a CSV to an Azure Data Lake Storage but when the file system/container does not exist the code breaks. I have also read through the documentation but I cannot seem to find anything helpful for this situation.

How do I go about creating a container in Azure Data Lake Storage if the container specified by the user does not exist?

Current Code:

    try:
        file_system_client = service_client.get_file_system_client(file_system="testfilesystem")
    except Exception:
        file_system_client = service_client.create_file_system(file_system="testfilesystem")

Traceback:

(FilesystemNotFound) The specified filesystem does not exist.
RequestId:XXXX
Time:2021-03-31T13:39:21.8860233Z

Answer 1

The try catch pattern should be not used here since the Azure Data lake gen2 library has the built in exists() method for file_system_client.

First, make sure you've installed the latest version library: azure-storage-file-datalake 12.3.0. If you're not sure which version you're using, please use pip show azure-storage-file-datalake command to check the current version.

Then you can use the code below:

from azure.storage.filedatalake import DataLakeServiceClient

service_client = DataLakeServiceClient(account_url="{}://{}.dfs.core.windows.net".format(
           "https", "xxx"), credential="xxx")

#the get_file_system_client method will not throw error if the file system does not exist, if you're using the latest library 12.3.0
file_system_client = service_client.get_file_system_client("filesystem333")

print("the file system exists: " + str(file_system_client.exists()))

#create the file system if it does not exist
if not file_system_client.exists():
    file_system_client.create_file_system()
    print("the file system is created.")

#other code

I've tested it locally, it can work successfully: