有没有一种简单的方法可以从amazon的ElasticMapReduce（emr）下运行的驱动程序节点获取当前作业的应用程序ID？这是在群集模式下运行spark。
现在我正在使用运行 map() 对辅助进程执行的读取 CONTAINER_ID 环境变量。这似乎效率低下。代码如下：

def applicationIdFromEnvironment():
    return "_".join(['application'] + os.environ['CONTAINER_ID'].split("_")[1:3])

def applicationId():
    """Return the Yarn (or local) applicationID.
    The environment variables are only set if we are running in a Yarn container.
    """

    # First check to see if we are running on the worker...
    try:
        return applicationIdFromEnvironment()
    except KeyError:
        pass

    # Perhaps we are running on the driver? If so, run a Spark job that finds it.
    try:
        from pyspark import SparkConf, SparkContext
        sc = SparkContext.getOrCreate()
        if "local" in sc.getConf().get("spark.master"):
            return f"local{os.getpid()}"
        # Note: make sure that the following map does not require access to any existing module.
        appid = sc.parallelize([1]).map(lambda x: "_".join(['application'] + os.environ['CONTAINER_ID'].split("_")[1:3])).collect()
        return appid[0]
    except ImportError:
        pass

    # Application ID cannot be determined.
    return f"unknown{os.getpid()}"