Windows Spark集群REST API提交任务遇ERROR空指针异常求助

我在Windows系统部署了Spark集群，尝试通过REST API提交一个简单的HelloWorld Python任务，代码如下：

from pyspark.sql import SparkSession
def main(args):
    print('hello world')
    return 0
if __name__ == '__main__':
  main(None)

提交任务使用的URL为：http://<Master IP>:6066/v1/submissions/create
请求体如下：

{
    "appResource": "file:../../helloworld.py",
    "sparkProperties": {
        "spark.executor.memory": "2g",
        "spark.master": "spark://<Master IP>:7077",
        "spark.app.name": "Spark REST API - Hello world",
        "spark.driver.memory": "2g",
        "spark.eventLog.enabled": "false",
        "spark.driver.cores": "2",
        "spark.submit.deployMode": "cluster",
        "spark.driver.supervise": "true"
    },
    "clientSparkVersion": "3.3.1",
    "mainClass": "org.apache.spark.deploy.SparkSubmit",
    "environmentVariables": {
        "SPARK_ENV_LOADED": "1"
    },
    "action": "CreateSubmissionRequest",
    "appArgs": [
        "../../helloworld.py", "80"
    ]
}

通过Postman发送请求后，得到成功提交的响应：

{
    "action": "CreateSubmissionResponse",
    "message": "Driver successfully submitted as driver-20221216112633-0005",
    "serverSparkVersion": "3.3.1",
    "submissionId": "driver-20221216112633-0005",
    "success": true
}

但查询任务状态（URL：http://<Master IP>:6066/v1/submissions/status/driver-20221216112633-0005）时，返回driverState为ERROR，出现NullPointerException：

{
    "action": "SubmissionStatusResponse",
    "driverState": "ERROR",
    "message": "Exception from the cluster:\njava.lang.NullPointerException\n\torg.apache.spark.deploy.worker.DriverRunner.downloadUserJar(DriverRunner.scala:158)\n\torg.apache.spark.deploy.worker.DriverRunner.prepareAndRunDriver(DriverRunner.scala:179)\n\torg.apache.spark.deploy.worker.DriverRunner$$anon$2.run(DriverRunner.scala:99)",
    "serverSparkVersion": "3.3.1",
    "submissionId": "driver-20221216112633-0005",
    "success": true,
    "workerHostPort": "10.9.8.120:56060",
    "workerId": "worker-20221216093629-<IP>-56060"
}

我原本预期这个简单的HelloWorld任务会处于RUNNING或FINISHED状态，不清楚错误原因及排查方向，特此求助。

2022-01-12 更新：
我已找到解决方案：需要确保appResource和spark.jars中指定的py/jar文件能被集群所有节点访问，比如使用网络共享路径：

{
    "appResource": "file:////Servername/somefolder/HelloWorld.jar",
    ...
    "spark.jars": "file:////Servername/someFolder/HelloWorld.jar",
    ...
}

希望能帮到其他人，同时想请教：为何提交任务到Master后，仍需所有节点都能访问该文件？

内容的提问来源于stack exchange，提问作者samsal77