从Spark Worker访问环境变量

Question

我有一个需要访问DynamoDB表的应用程序。每个工作人员自己建立与数据库的连接。

我已将AWS_ACCESS_KEY_ID和AWS_SECRET_ACCESS_KEY同时添加到主人和工作人员spark-env.sh文件中。我还使用sh运行该文件以确保变量已导出。

当代码运行时，我总是得到错误：

Caused by: com.amazonaws.AmazonClientException: Unable to load AWS credentials from any provider in the chain 
    at com.amazonaws.auth.AWSCredentialsProviderChain.getCredentials(AWSCredentialsProviderChain.java:131) 
    at com.amazonaws.http.AmazonHttpClient.getCredentialsFromContext(AmazonHttpClient.java:774) 
    at com.amazonaws.http.AmazonHttpClient.executeOneRequest(AmazonHttpClient.java:800) 
    at com.amazonaws.http.AmazonHttpClient.executeHelper(AmazonHttpClient.java:695) 
    at com.amazonaws.http.AmazonHttpClient.doExecute(AmazonHttpClient.java:447) 
    at com.amazonaws.http.AmazonHttpClient.executeWithTimer(AmazonHttpClient.java:409) 
    at com.amazonaws.http.AmazonHttpClient.execute(AmazonHttpClient.java:358) 
    at com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient.doInvoke(AmazonDynamoDBClient.java:2051) 
    at com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient.invoke(AmazonDynamoDBClient.java:2021) 
    at com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient.describeTable(AmazonDynamoDBClient.java:1299) 
    at com.amazon.titan.diskstorage.dynamodb.DynamoDBDelegate.describeTable(DynamoDBDelegate.java:635) 
    ... 27 more 

看来，AWS SDK未能加载即使它们导出的证书。我应该尝试什么类型的解决方案？

Answer 1

您可以使用SparkConf上的​​方法。 E.g

/** 
    * Set an environment variable to be used when launching executors for this application. 
    * These variables are stored as properties of the form spark.executorEnv.VAR_NAME 
    * (for example spark.executorEnv.PATH) but this method makes them easier to set. 
    */ 
    def setExecutorEnv(variable: String, value: String): SparkConf = { 
    set("spark.executorEnv." + variable, value) 
    } 

而且

/** 
    * Set multiple environment variables to be used when launching executors. 
    * These variables are stored as properties of the form spark.executorEnv.VAR_NAME 
    * (for example spark.executorEnv.PATH) but this method makes them easier to set. 
    */ 
    def setExecutorEnv(variables: Seq[(String, String)]): SparkConf = { 
    for ((k, v) <- variables) { 
     setExecutorEnv(k, v) 
    } 
    this 
    } 

你可能会考虑其他选项，如设置Java系统属性：SparkConf会自动接他们回家。