Reading parquet file from ADLS gen2 using service principal

Question

I am using azure-storage-file-datalake package to connect with ADLS gen2

from azure.identity import ClientSecretCredential

# service principal credential
tenant_id = 'xxxxxxx'
client_id = 'xxxxxxxxx'
client_secret = 'xxxxxxxx'
storage_account_name = 'xxxxxxxx'

credential = ClientSecretCredential(tenant_id, client_id, client_secret)

service_client = DataLakeServiceClient(account_url="{}://{}.dfs.core.windows.net".format(
        "https", storage_account_name), credential=credential) # I have also tried blob instead of dfs in account_url

Folder structure in ADLS gen2 from where I have to read parquet file look like this. Inside container of ADLS gen2 we folder_a which contain folder_b in which there is parquet file.

folder_a
  |-folder_b
      parquet_file1

from gen1 storage we used to read parquet file like this.

from azure.datalake.store import lib
from azure.datalake.store.core import AzureDLFileSystem
import pyarrow.parquet as pq

adls = lib.auth(tenant_id=directory_id,
            client_id=app_id,
            client_secret=app_key)
adl = AzureDLFileSystem(adls, store_name=adls_name) 

f = adl.open(file, 'rb') # 'file is parquet file with path of parquet file folder_a/folder_b/parquet_file1'
table = pq.read_table(f)

How do we proceed with gen2 storage, we are stuck at this point

http://peter-hoffmann.com/2020/azure-data-lake-storage-gen-2-with-python.html is the link that we have followed.

Note - We are not using databrick to do this

Answer 1

Regarding the issue, please refer to the following code

from azure.identity import ClientSecretCredential
from azure.storage.filedatalake import DataLakeServiceClient
import pyarrow.parquet as pq
import io

client_id = ''
client_secret = ''
tenant_id = ''
credential = ClientSecretCredential(tenant_id, client_id, client_secret)

storage_account_name = 'testadls05'
service_client = DataLakeServiceClient(account_url="{}://{}.dfs.core.windows.net".format(
    "https", storage_account_name), credential=credential)
file_system = '<container name>'
file_system_client = service_client.get_file_system_client(file_system)

file_path = ''
file_client = file_system_client.get_file_client(file_path)
data = file_client.download_file(0)
with io.BytesIO() as b:
    data.readinto(b)
    table = pq.read_table(b)
    print(table)