问题描述
编写Python Function，并且在Function中通过 subprocess 调用powershell.exe 执行 powershell脚本。
import azure.functions as func import logging import subprocess app = func.FunctionApp(http_auth_level=func.AuthLevel.FUNCTION) def run(cmd): completed = subprocess.run(["powershell", "-Command", cmd], capture_output=True) return completed .route(route="http_trigger") def http_trigger(req: func.HttpRequest) -> func.HttpResponse: logging.info('Python HTTP trigger function processed a request.') name = req.params.get('name') if not name: try: req_body = req.get_json() except ValueError: pass else: name = req_body.get('name') hello_command = "Write-Host 'Hello Wolrd!"+name+"'" hello_info = run(hello_command) if hello_info.returncode != 0: logging.info("An error occured: %s", hello_info.stderr) else: logging.info("Hello command executed successfully!") logging.info("-------------------------") logging.info(str(hello_info.stdout)) if name: return func.HttpResponse(f"Hello, {name}. This HTTP triggered function executed successfully.") else: return func.HttpResponse( "This HTTP triggered function executed successfully. Pass a name in the query string or in the request body for a personalized response.", status_code=200 )
本地测试环境为Windows，执行成功！
当通过VS Code部署到Azure Function App后，在门户上调用就出现 500 Internal Server Error 错误。
这是什么情况呢？
问题解答
查看Azure Function的后台日志，进入Kudu站点(https://<your function app name>.scm.chinacloudsites.cn/newui), 查看 Logfiles/Application/Functions/Function/<your function name>/xxxxxxx_xxxxx.log
2023-10-07T11:32:41.605 [Information] Executing 'Functions.http_trigger' (Reason='This function was programmatically called via the host APIs.', Id=353799e7-fb4f-4ec9-bb42-ed2cafbda9da) 2023-10-07T11:32:41.786 [Information] Python HTTP trigger function processed a request. 2023-10-07T11:32:41.874 [Error] Executed 'Functions.http_trigger' (Failed, Id=353799e7-fb4f-4ec9-bb42-ed2cafbda9da, Duration=275ms) Result: Failure Exception: FileNotFoundError: [Errno 2] No such file or directory: 'powershell' Stack: File "/azure-functions-host/workers/python/3.11/LINUX/X64/azure_functions_worker/dispatcher.py", line 479, in _handle__invocation_request call_result = await self._loop.run_in_executor( ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/usr/local/lib/python3.11/concurrent/futures/thread.py", line 58, in run result = self.fn(*self.args, **self.kwargs) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/azure-functions-host/workers/python/3.11/LINUX/X64/azure_functions_worker/dispatcher.py", line 752, in _run_sync_func return ExtensionManager.get_sync_invocation_wrapper(context, ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/azure-functions-host/workers/python/3.11/LINUX/X64/azure_functions_worker/extension.py", line 215, in _raw_invocation_wrapper result = function(**args) ^^^^^^^^^^^^^^^^ File "/home/site/wwwroot/function_app.py", line 26, in http_trigger hello_info = run(hello_command) ^^^^^^^^^^^^^^^^^^ File "/home/site/wwwroot/function_app.py", line 9, in run completed = subprocess.run(["powershell", "-Command", cmd], capture_output=True) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/usr/local/lib/python3.11/subprocess.py", line 548, in run with Popen(*popenargs, **kwargs) as process: ^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/usr/local/lib/python3.11/subprocess.py", line 1026, in __init__ self._execute_child(args, executable, preexec_fn, close_fds, File "/usr/local/lib/python3.11/subprocess.py", line 1950, in _execute_child raise child_exception_type(errno_num, err_msg, err_filename)
发现异常 “ Exception: FileNotFoundError: [Errno 2] No such file or directory: 'powershell' ”，
进入Kudu的Bash 或 SSH 页面，通过powershell 和 pwsh 命令，验证当前环境是否有安装PowerShell
因为Azure中创建的Python Function均为Linux系统，而Linux中没有安装Powershell，所以才出现Python代码中调用Python失败。
那是否可以自己在Function App的环境中安装Powershell呢？ 答案不可以。
那是否有其他的方案呢？
有的，Azure Function可以创建Powershell Function，把PowerShell作为一个HTTP Trigger的Function，在Python Function中调用Powershell Function的URL，就可以实现在Azure上调用PowerShell的目的。
参考资料
Installing PowerShell on Ubuntu ： https://learn.microsoft.com/en-us/powershell/scripting/install/install-ubuntu?view=powershell-7.3
在 Azure 中使用 Visual Studio Code 创建 PowerShell 函数：https://docs.azure.cn/zh-cn/azure-functions/create-first-function-vs-code-powershell
在 Azure 中使用 Visual Studio Code 创建 Python 函数 ： https://docs.azure.cn/zh-cn/azure-functions/create-first-function-vs-code-python?pivots=python-mode-configuration
