在Python函数中使用AzureML时“失败异常:AzureML：[Errno 30]只读文件系统”

Question

问题

我正在尝试准备并提交一个新的实验，让Azure机器从Python中的Azure函数中学习。因此，我为Azure工作区注册了一个新的数据集，其中包含使用dataset.register(...的ML模型的培训数据。但是，当我尝试用下面的代码创建此数据集时

dataset = Dataset.Tabular.from_delimited_files(path = datastore_paths)

然后我得到一个Failure Exception: OSError: [Errno 30] Read-only file system ...。

想法

1. 我知道，如果可能的话，我不应该从Azure函数中写入文件系统。但实际上我不想给本地文件系统写任何东西。我只想创建dataset作为对datastore_path下blob存储的引用，然后将其注册到工作区。但是from_delimited_files似乎无论如何都在尝试写入文件系统(可能是缓存吗？)。
2. 我还知道有一个临时文件夹允许写入临时文件。然而，我相信我不能真正控制这个方法在哪里写入数据。我已经尝试过使用os.chdir(tempfile.gettempdir())在函数调用之前将当前的工作目录更改为这个临时文件夹，但这没有帮助。

还有其他想法吗？我不认为我做了什么特别不寻常的事.

详细信息

我使用python3.7和azuremlSDK1.9.0，我可以在本地运行python脚本，不会出现问题。我目前使用Azure函数扩展版本0.23.0 (以及用于CI/CD的Azure DevOps管道)从DevOps部署。

下面是我的完整堆栈跟踪：

Microsoft.Azure.WebJobs.Host.FunctionInvocationException: Exception while executing function: Functions.HttpTrigger_Train
 ---> Microsoft.Azure.WebJobs.Script.Workers.Rpc.RpcException: Result: Failure
Exception: OSError: [Errno 30] Read-only file system: '/home/site/wwwroot/.python_packages/lib/site-packages/dotnetcore2/bin/deps.lock'
Stack:   File "/azure-functions-host/workers/python/3.7/LINUX/X64/azure_functions_worker/dispatcher.py", line 345, in _handle__invocation_request
    self.__run_sync_func, invocation_id, fi.func, args)
  File "/usr/local/lib/python3.7/concurrent/futures/thread.py", line 57, in run
    result = self.fn(*self.args, **self.kwargs)
  File "/azure-functions-host/workers/python/3.7/LINUX/X64/azure_functions_worker/dispatcher.py", line 480, in __run_sync_func
    return func(**params)
  File "/home/site/wwwroot/HttpTrigger_Train/__init__.py", line 11, in main
    train()
  File "/home/site/wwwroot/shared_code/train.py", line 70, in train
    dataset = Dataset.Tabular.from_delimited_files(path = datastore_paths)
  File "/home/site/wwwroot/.python_packages/lib/site-packages/azureml/data/_loggerfactory.py", line 126, in wrapper
    return func(*args, **kwargs)
  File "/home/site/wwwroot/.python_packages/lib/site-packages/azureml/data/dataset_factory.py", line 308, in from_delimited_files
    quoting=support_multi_line)
  File "/home/site/wwwroot/.python_packages/lib/site-packages/azureml/dataprep/api/readers.py", line 100, in read_csv
    df = Dataflow._path_to_get_files_block(path, archive_options)
  File "/home/site/wwwroot/.python_packages/lib/site-packages/azureml/dataprep/api/dataflow.py", line 2387, in _path_to_get_files_block
    return datastore_to_dataflow(path)
  File "/home/site/wwwroot/.python_packages/lib/site-packages/azureml/dataprep/api/_datastore_helper.py", line 41, in datastore_to_dataflow
    datastore, datastore_value = get_datastore_value(source)
  File "/home/site/wwwroot/.python_packages/lib/site-packages/azureml/dataprep/api/_datastore_helper.py", line 83, in get_datastore_value
    _set_auth_type(workspace)
  File "/home/site/wwwroot/.python_packages/lib/site-packages/azureml/dataprep/api/_datastore_helper.py", line 134, in _set_auth_type
    get_engine_api().set_aml_auth(SetAmlAuthMessageArgument(AuthType.SERVICEPRINCIPAL, json.dumps(auth)))
  File "/home/site/wwwroot/.python_packages/lib/site-packages/azureml/dataprep/api/engineapi/api.py", line 18, in get_engine_api
    _engine_api = EngineAPI()
  File "/home/site/wwwroot/.python_packages/lib/site-packages/azureml/dataprep/api/engineapi/api.py", line 55, in __init__
    self._message_channel = launch_engine()
  File "/home/site/wwwroot/.python_packages/lib/site-packages/azureml/dataprep/api/engineapi/engine.py", line 300, in launch_engine
    dependencies_path = runtime.ensure_dependencies()
  File "/home/site/wwwroot/.python_packages/lib/site-packages/dotnetcore2/runtime.py", line 141, in ensure_dependencies
    with _FileLock(deps_lock_path, raise_on_timeout=timeout_exception):
  File "/home/site/wwwroot/.python_packages/lib/site-packages/dotnetcore2/runtime.py", line 113, in __enter__
    self.acquire()
  File "/home/site/wwwroot/.python_packages/lib/site-packages/dotnetcore2/runtime.py", line 72, in acquire
    self.lockfile = os.open(self.lockfile_path, os.O_CREAT | os.O_EXCL | os.O_RDWR)

   at Microsoft.Azure.WebJobs.Script.Description.WorkerFunctionInvoker.InvokeCore(Object[] parameters, FunctionInvocationContext context) in /src/azure-functions-host/src/WebJobs.Script/Description/Workers/WorkerFunctionInvoker.cs:line 85
   at Microsoft.Azure.WebJobs.Script.Description.FunctionInvokerBase.Invoke(Object[] parameters) in /src/azure-functions-host/src/WebJobs.Script/Description/FunctionInvokerBase.cs:line 85
   at Microsoft.Azure.WebJobs.Script.Description.FunctionGenerator.Coerce[T](Task`1 src) in /src/azure-functions-host/src/WebJobs.Script/Description/FunctionGenerator.cs:line 225
   at Microsoft.Azure.WebJobs.Host.Executors.FunctionInvoker`2.InvokeAsync(Object instance, Object[] arguments) in C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Executors\FunctionInvoker.cs:line 52
   at Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.InvokeAsync(IFunctionInvoker invoker, ParameterHelper parameterHelper, CancellationTokenSource timeoutTokenSource, CancellationTokenSource functionCancellationTokenSource, Boolean throwOnTimeout, TimeSpan timerInterval, IFunctionInstance instance) in C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Executors\FunctionExecutor.cs:line 587
   at Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.ExecuteWithWatchersAsync(IFunctionInstanceEx instance, ParameterHelper parameterHelper, ILogger logger, CancellationTokenSource functionCancellationTokenSource) in C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Executors\FunctionExecutor.cs:line 532
   at Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.ExecuteWithLoggingAsync(IFunctionInstanceEx instance, ParameterHelper parameterHelper, IFunctionOutputDefinition outputDefinition, ILogger logger, CancellationTokenSource functionCancellationTokenSource) in C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Executors\FunctionExecutor.cs:line 470
   at Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.ExecuteWithLoggingAsync(IFunctionInstanceEx instance, FunctionStartedMessage message, FunctionInstanceLogEntry instanceLogEntry, ParameterHelper parameterHelper, ILogger logger, CancellationToken cancellationToken) in C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Executors\FunctionExecutor.cs:line 278
   --- End of inner exception stack trace ---
   at Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.ExecuteWithLoggingAsync(IFunctionInstanceEx instance, FunctionStartedMessage message, FunctionInstanceLogEntry instanceLogEntry, ParameterHelper parameterHelper, ILogger logger, CancellationToken cancellationToken) in C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Executors\FunctionExecutor.cs:line 325
   at Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.TryExecuteAsyncCore(IFunctionInstanceEx functionInstance, CancellationToken cancellationToken) in C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Executors\FunctionExecutor.cs:line 117

Answer 1

这个问题是我的虚拟环境中的一个不兼容的OS版本。

非常感谢PramodValavala-MSFT为他创建一个码头容器的想法！按照他的建议，我突然收到了dataset = Dataset.Tabular.from_delimited_files(path = datastore_paths)命令的以下错误消息：

例外: NotImplementedError:不支持的Linux发行版debian 10。

这让我想起了蔚蓝机器学习文档中的以下警告：

一些dataset类依赖于，它只与64位Python兼容。对于Linux用户，这些类只支持以下发行版：(7，8)、Ubuntu (14.04、16.04、18.04)、Fedora (27、28)、Debian (8、9)和CentOS (7)。

选择预定义的坞映像2.0-python3.7 (运行Debian 9)而不是3.0-python3.7 (运行Debian 10)解决了这个问题(参见/microsoft-azure-functions python)。

我怀疑我最初使用的默认虚拟环境也运行在不兼容的操作系统上。