Question

我一直试图通过我为Apache Spark项目编写的一些单元/集成测试来追踪问题。

使用Spark 1.1.1时，我的测试通过了。当我尝试升级到1.4.0（也尝试过1.4.1）时，测试开始失败。

我设法将重现问题所需的代码减少到下面的小集成测试。

有趣的是，如果我在测试中注释掉@RunWith注释，那么测试会正确传递。显然，我不需要@RunWith注释来进行这种减少测试，但真正的测试相当广泛地使用了模拟，所以我不必使用PowerMock。

package com.example;

import org.apache.spark.SparkConf;
import org.apache.spark.streaming.Duration;
import org.apache.spark.streaming.api.java.JavaStreamingContext;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.powermock.modules.junit4.PowerMockRunner;

@RunWith(PowerMockRunner.class)
public class SampleTest {

    @Before
    public void setup() throws Exception {
        SparkConf conf = new     SparkConf(false).setMaster("local[2]").setAppName("My app");
        JavaStreamingContext jsc = new JavaStreamingContext(conf, new Duration(1000));
    }

    @Test
    public void exampleTest() {
    }
}

以下是我看到的例外

java.io.IOException: failure to login
    at org.apache.hadoop.security.UserGroupInformation.loginUserFromSubject(UserGroupInformation.java:796)
    at org.apache.hadoop.security.UserGroupInformation.getLoginUser(UserGroupInformation.java:748)
    at org.apache.hadoop.security.UserGroupInformation.getCurrentUser(UserGroupInformation.java:621)
    at org.apache.spark.util.Utils$$anonfun$getCurrentUserName$1.apply(Utils.scala:2162)
    at org.apache.spark.util.Utils$$anonfun$getCurrentUserName$1.apply(Utils.scala:2162)
    at scala.Option.getOrElse(Option.scala:120)
    at org.apache.spark.util.Utils$.getCurrentUserName(Utils.scala:2162)
    at org.apache.spark.SparkContext.<init>(SparkContext.scala:301)
    at org.apache.spark.streaming.StreamingContext$.createNewSparkContext(StreamingContext.scala:842)
    at org.apache.spark.streaming.StreamingContext.<init>(StreamingContext.scala:80)
    at org.apache.spark.streaming.api.java.JavaStreamingContext.<init>(JavaStreamingContext.scala:133)
    at com.example.SampleTest.setup(SampleTest.java:19)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.junit.internal.runners.MethodRoadie.runBefores(MethodRoadie.java:133)
    at org.junit.internal.runners.MethodRoadie.runBeforesThenTestThenAfters(MethodRoadie.java:96)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.executeTest(PowerMockJUnit44RunnerDelegateImpl.java:294)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTestInSuper(PowerMockJUnit47RunnerDelegateImpl.java:127)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTest(PowerMockJUnit47RunnerDelegateImpl.java:82)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.runBeforesThenTestThenAfters(PowerMockJUnit44RunnerDelegateImpl.java:282)
    at org.junit.internal.runners.MethodRoadie.runTest(MethodRoadie.java:87)
    at org.junit.internal.runners.MethodRoadie.run(MethodRoadie.java:50)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.invokeTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:207)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods(PowerMockJUnit44RunnerDelegateImpl.java:146)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$1.run(PowerMockJUnit44RunnerDelegateImpl.java:120)
    at org.junit.internal.runners.ClassRoadie.runUnprotected(ClassRoadie.java:34)
    at org.junit.internal.runners.ClassRoadie.runProtected(ClassRoadie.java:44)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run(PowerMockJUnit44RunnerDelegateImpl.java:122)
    at org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java:106)
    at org.powermock.modules.junit4.common.internal.impl.AbstractCommonPowerMockRunner.run(AbstractCommonPowerMockRunner.java:53)
    at org.powermock.modules.junit4.PowerMockRunner.run(PowerMockRunner.java:59)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
Caused by: javax.security.auth.login.LoginException: Can't find user name
    at org.apache.hadoop.security.UserGroupInformation$HadoopLoginModule.commit(UserGroupInformation.java:197)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at javax.security.auth.login.LoginContext.invoke(LoginContext.java:784)
    at javax.security.auth.login.LoginContext.access$000(LoginContext.java:203)
    at javax.security.auth.login.LoginContext$5.run(LoginContext.java:721)
    at javax.security.auth.login.LoginContext$5.run(LoginContext.java:719)
    at java.security.AccessController.doPrivileged(Native Method)
    at javax.security.auth.login.LoginContext.invokeCreatorPriv(LoginContext.java:718)
    at javax.security.auth.login.LoginContext.login(LoginContext.java:591)
    at org.apache.hadoop.security.UserGroupInformation.loginUserFromSubject(UserGroupInformation.java:771)
    ... 38 more

各种依赖项的版本如下所示

hadoop-client 2.6
apache spark 1.4.0 / 1.4.1
junit 4.12
easy mock 3.31
power mock 1.6.2

我已尝试使用各种版本的Spark。上述测试通过了以下版本的Spark

1.1.1
1.2.2

从Spark 1.3.0开始失败。

我需要改变什么才能让它发挥作用？

Answer 1

查看SparkContext的源代码，这是在尝试获取当前用户名时导致异常的行。在version 1.2中有一个回退默认值SparkContext.SPARK_UNKNOWN_USER，并且它不需要当前登录用户：

 // Set SPARK_USER for user who is running SparkContext.
 val sparkUser = Option {
     Option(System.getenv("SPARK_USER")).getOrElse(System.getProperty("user.name"))
  }.getOrElse {
      SparkContext.SPARK_UNKNOWN_USER
  }

version 1.3中引入的此代码不再具有默认用户，因此您不会在早期版本中出现此错误：

// Set SPARK_USER for user who is running SparkContext.
val sparkUser = Utils.getCurrentUserName()

这会调用Utils中的following code：

/**
   * Returns the current user name. This is the currently logged in user, unless that's been
   * overridden by the `SPARK_USER` environment variable.
   */
  def getCurrentUserName(): String = {
    Option(System.getenv("SPARK_USER"))
      .getOrElse(UserGroupInformation.getCurrentUser().getShortUserName())
  }

如果您设置环境变量SPARK_USER，您应该能够阻止分支到UserGroupInformation，从而导致您的异常。

UserGroupInformation是一个Hadoop安全类，看起来使用PowerMock阻止它正常工作。

Apache Spark Streaming

1 个答案: