This request is not authorized to perform this operation while trying to read a blob from Data Lake gen2

Question

I would like to copy a blob from one Datalake to another one, here is my simple code to do this job:

    DataLakeFileSystemClient sourceDataLakeFileSystemClient = StorageAccountDataLakeHelper.GetDataLakeFileSystemClient(SourceContainer, SOURCE_DATALAKE_NAME, SOURCE_DATA_LAKE_ACCESS_KEY);
    DataLakeFileSystemClient taregetDataLakeFileSystemClient = StorageAccountDataLakeHelper.GetDataLakeFileSystemClient(TargetContainer, TARGET_DATALAKE_NAME, TARTGET_DATA_LAKE_ACCESS_KEY);
    DataLakeDirectoryClient sourcedirectoryClient = sourceDataLakeFileSystemClient.GetDirectoryClient("folder1/folder2/");
    DataLakeFileClient sourcefileClient = sourcedirectoryClient.GetFileClient("myfile.csv.csv");    
    Stream reader= await sourcefileClient.OpenReadAsync();
    DataLakeDirectoryClient targetdirectoryClient = taregetDataLakeFileSystemClient.GetDirectoryClient("folder1/folder2/");
    DataLakeFileClient targetfileClient = await targetdirectoryClient.CreateFileAsync("myfile.csv.csv");

The authentication based on access key as you can see. I can run this code localy successfully. but if I publishe to a function app in azure I get this exception:

An unhandled exception of type 'Azure.RequestFailedException' occurred in System.Private.CoreLib.dll
Service request failed.
Status: 403 (This request is not authorized to perform this operation.)
ErrorCode: AuthorizationFailure

Headers:
Transfer-Encoding: chunked
Server: Microsoft-HTTPAPI/2.0
x-ms-request-id: 0d261530-201e-009b-5a39-3c8d7e000000
x-ms-client-request-id: 13ec55f9-7a99-4959-bb1c-024e5848a414
x-ms-error-code: AuthorizationFailure
Date: Wed, 28 Apr 2021 14:20:59 GMT

Exception occures on this line:

Stream reader= await sourcefileClient.OpenReadAsync();

What should I do to solve this problem?

Answer 1

I use below code and deploy to azure, it seems work fine:

using System;
using System.IO;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Azure.WebJobs;
using Microsoft.Azure.WebJobs.Extensions.Http;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Logging;
using Newtonsoft.Json;
using Azure.Storage.Files.DataLake;

namespace FunctionApp110
{
    public static class Function1
    {
        [FunctionName("Function1")]
        public static async Task<IActionResult> Run(
            [HttpTrigger(AuthorizationLevel.Anonymous, "get", "post", Route = null)] HttpRequest req,
            ILogger log)
        {
            string str = "DefaultEndpointsProtocol=https;AccountName=0730bowmanwindow;AccountKey=xxxxxx;EndpointSuffix=core.windows.net";
            string sourcefs = "source";
            string sinkfs = "sink";
            string sourcedir = "test";
            string sinkdir = "test";
            string sourcefile = "source.txt";
            string sinkfile = "sink.txt";
            DataLakeFileSystemClient sourcefilesystemclient = new DataLakeFileSystemClient(str, sourcefs);
            DataLakeFileSystemClient sinkfilesystemclient = new DataLakeFileSystemClient(str, sinkfs);
            var sourcedirectoryclient = sourcefilesystemclient.GetDirectoryClient(sourcedir);
            var sinkdirectoryclient = sinkfilesystemclient.GetDirectoryClient(sinkdir);
            var sourcefileclient = sourcedirectoryclient.GetFileClient(sourcefile);
            Stream reader = sourcefileclient.OpenRead();
            MemoryStream msreader = new MemoryStream();
            reader.CopyTo(msreader);
            msreader.Position = 0;
            DataLakeFileClient sinkfileclient = sinkdirectoryclient.CreateFile(sinkfile);
            sinkfileclient.Append(msreader, 0);
            sinkfileclient.Flush(sourcefileclient.GetProperties().Value.ContentLength);
            return new OkObjectResult("This is a test.");
        }
    }
}

You can try it.:)