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tajjallarukshan's avatar
tajjallarukshan
Frequent Visitor
2 years ago
Solved

Issue listing/Uploading/modifying files in lakehouse using python

Summary – I have created a Lakehouse in Power BI Service and are trying to test the connectivity to the Lakehouse via Python following the documentation here: https://learn.microsoft.com/en-us/fabr...
data engineering
lakehouse
notebook
  • tajjallarukshan's avatar
    tajjallarukshan
    2 years ago

    Hello,

     

    I have found the cause of it, and it has to do with the nomenclature you follow for naming your lakehouse, workspace and all subsequent objects. They should not have upper case letters or special characters. That solved the problem for us!

tajjallarukshan's avatar
tajjallarukshan
Frequent Visitor
2 years ago

Hi Yang,

 

I had updated the code posted here with different names to maintain integrity of the organization.

I have validated the names for any typos or additional space, but thats not the case. 

 

Copying workspace name from the portal and ensuring to copy name of lakehouse as is has been my approach. So there is no chance of such misses. 

 

 

However, Here is my detailed analysis upon figuring out where the code is creating a problem:

 


import os
from azure.identity import DefaultAzureCredential
from azure.storage.filedatalake import DataLakeServiceClient

# Set your account name and workspace information here
ACCOUNT_NAME = "onelake"
DATA_PATH = "LH_MVP_1.Lakehouse/Files/Processed/"

def list_file_systems(service_client😞
    try:
        # Listing file systems might be restricted. We can ensure to handle this error or validate this part
        file_systems = service_client.list_file_systems()
        for fs in file_systems:
            print("File system name:", fs.name)
    except Exception as e:
        print("An error occurred while listing file systems:", str(e))

def list_paths(file_system_client😞
    try:
        # List paths within the specified folder
        paths = file_system_client.get_paths(path=DATA_PATH)
        print(f"Listing paths:")
        for path in paths:
            print("Path name:", path.name)
    except Exception as e:
        print(f"An error occurred while listing paths", str(e))

def main(file_system_name😞
    # Create a service client using the default Azure credential
    account_url = f"https://{ACCOUNT_NAME}.dfs.fabric.microsoft.com"
    token_credential = DefaultAzureCredential()
    service_client = DataLakeServiceClient(account_url, credential=token_credential)
   
    # List file systems to test if the service client works fine
    list_file_systems(service_client)

    # Create a file system client
    file_system_client = service_client.get_file_system_client(file_system_name)
 
     # List file systems to test if the service client works fine
    list_paths(file_system_client)
   

if __name__ == "__main__":
       main("FABRIC MVP 1")

Output:
 

So this shows:

1. Authentication is successful

2. All workspaces are being listed as file systems successfully

3. But error appears while attempting to list paths inside a specific workspace

Do you know if the format in which the data path is passed is correct here "file_system_client.get_paths(path=DATA_PATH)"?

My use case is to upload files to the lakehouse via Python. I followed the approach in this link, and I was able to successfully list/ upload and update files in lakehouse 2 months ago. But the same code abruptly stopped working just after a week of its successful run. I have a ticket with Microsoft for the same, but its not heading in any direction to get this working.

JDT's avatar
JDT
Frequent Visitor
2 years ago

Hi, 

have you found a solution to this problem? We experiencing exactly the same thing. Our Python Scripts suddenly stop working without changing anything on our site.

  • tajjallarukshan's avatar
    tajjallarukshan
    Frequent Visitor
    2 years ago

    Hello,

     

    I have found the cause of it, and it has to do with the nomenclature you follow for naming your lakehouse, workspace and all subsequent objects. They should not have upper case letters or special characters. That solved the problem for us!

    • Narayan212's avatar
      Narayan212
      New Member
      1 year ago

      Hi tajjallarukshan, I'm having the same problem. Even after your comment I tried to create another lakehouse with lower case letters and not special characters and still unable to access or list the paths. I am using the client id, secret and tenant id for the authentication. I am able to print file system name as you are trying in the code and it is working fine. But once I try to upload any file or try to list path then I am getting the same error. Can you please help me out here

      • JDT's avatar
        JDT
        Frequent Visitor
        1 year ago

        Hi,

         

        what I have found out is, that whitespaces,* and | are evil. Do not use them in the workspace and lakehouse name. I couldnt find a clear rule. Even some names that are compliant with ADLS2's naming reference broke for me - naming-and-referencing-containers--blobs--and-metadata.