对接Kerberos认证Hadoop集群报DockerCredentialTokenIdentifier未找到

通过部署在Tomcat上的API对接开启Kerberos认证的Hadoop集群，执行HDFS文件上传操作时触发报错。
初步排查已排除基础配置问题：

• 集群侧keytab文件运行状态正常，可正常执行kinit命令读取HDFS内文件
• krb5.conf配置符合规范要求，默认realm及其他必填配置项均已正确配置

Exception in thread "main" java.util.ServiceConfigurationError: org.apache.hadoop.security.token.TokenIdentifier: Provider org.apache.hadoop.yarn.security.DockerCredentialTokenIdentifier not found
    at java.util.ServiceLoader.fail(ServiceLoader.java:239)
    at java.util.ServiceLoader.access$300(ServiceLoader.java:185)
    at java.util.ServiceLoader$LazyIterator.nextService(ServiceLoader.java:372)
    at java.util.ServiceLoader$LazyIterator.next(ServiceLoader.java:404)
    at java.util.ServiceLoader$1.next(ServiceLoader.java:480)
    at org.apache.hadoop.security.token.Token.getClassForIdentifier(Token.java:117)
    at org.apache.hadoop.security.token.Token.decodeIdentifier(Token.java:138)
    at org.apache.spark.deploy.security.HadoopFSDelegationTokenProvider$$anonfun$getTokenRenewalInterval$1$$anonfun$4.apply(HadoopFSDelegationTokenProvider.scala:116)
    at org.apache.spark.deploy.security.HadoopFSDelegationTokenProvider$$anonfun$getTokenRenewalInterval$1$$anonfun$4.apply(HadoopFSDelegationTokenProvider.scala:116)
    at scala.collection.TraversableLike$$anonfun$filterImpl$1.apply(TraversableLike.scala:248)
    at scala.collection.Iterator$class.foreach(Iterator.scala:891)
    at scala.collection.AbstractIterator.foreach(Iterator.scala:1334)
    at scala.collection.IterableLike$class.foreach(IterableLike.scala:72)
    at scala.collection.AbstractIterable.foreach(Iterable.scala:54)
    at scala.collection.TraversableLike$class.filterImpl(TraversableLike.scala:247)
    at scala.collection.TraversableLike$class.filter(TraversableLike.scala:259)
    at scala.collection.AbstractTraversable.filter(Traversable.scala:104)
    at org.apache.spark.deploy.security.HadoopFSDelegationTokenProvider$$anonfun$getTokenRenewalInterval$1.apply(HadoopFSDelegationTokenProvider.scala:115)
    at org.apache.spark.deploy.security.HadoopFSDelegationTokenProvider$$anonfun$getTokenRenewalInterval$1.apply(HadoopFSDelegationTokenProvider.scala:111)
    at scala.Option.flatMap(Option.scala:171)
    at org.apache.spark.deploy.security.HadoopFSDelegationTokenProvider.getTokenRenewalInterval(HadoopFSDelegationTokenProvider.scala:111)
    at org.apache.spark.deploy.security.HadoopFSDelegationTokenProvider.obtainDelegationTokens(HadoopFSDelegationTokenProvider.scala:53)
    at org.apache.spark.deploy.security.HadoopDelegationTokenManager$$anonfun$obtainDelegationTokens$2.apply(HadoopDelegationTokenManager.scala:132)
    at org.apache.spark.deploy.security.HadoopDelegationTokenManager$$anonfun$obtainDelegationTokens$2.apply(HadoopDelegationTokenManager.scala:130)
    at scala.collection.TraversableLike$$anonfun$flatMap$1.apply(TraversableLike.scala:241)
    at scala.collection.TraversableLike$$anonfun$flatMap$1.apply(TraversableLike.scala:241)
    at scala.collection.Iterator$class.foreach(Iterator.scala:891)
    at scala.collection.AbstractIterator.foreach(Iterator.scala:1334)
    at scala.collection.MapLike$DefaultValuesIterable.foreach(MapLike.scala:206)
    at scala.collection.TraversableLike$class.flatMap(TraversableLike.scala:241)
    at scala.collection.AbstractTraversable.flatMap(Traversable.scala:104)
    at org.apache.spark.deploy.security.HadoopDelegationTokenManager.obtainDelegationTokens(HadoopDelegationTokenManager.scala:130)
    at org.apache.spark.deploy.yarn.security.YARNHadoopDelegationTokenManager.obtainDelegationTokens(YARNHadoopDelegationTokenManager.scala:59)
    at org.apache.spark.deploy.yarn.Client.setupSecurityToken(Client.scala:309)
    at org.apache.spark.deploy.yarn.Client.createContainerLaunchContext(Client.scala:1013)
    at org.apache.spark.deploy.yarn.Client.submitApplication(Client.scala:178)
    at org.apache.spark.deploy.yarn.Client.run(Client.scala:1134)
    at org.apache.spark.deploy.yarn.YarnClusterApplication.start(Client.scala:1526)
    at org.apache.spark.deploy.SparkSubmit.org$apache$spark$deploy$SparkSubmit$$runMain(SparkSubmit.scala:849)
    at org.apache.spark.deploy.SparkSubmit.doRunMain$1(SparkSubmit.scala:167)
    at org.apache.spark.deploy.SparkSubmit.submit(SparkSubmit.scala:195)
    at org.apache.spark.deploy.SparkSubmit.doSubmit(SparkSubmit.scala:86)
    at org.apache.spark.deploy.SparkSubmit$$anon$2.doSubmit(SparkSubmit.scala:924)
    at org.apache.spark.deploy.SparkSubmit$.main(SparkSubmit.scala:933)
    at org.apache.spark.deploy.SparkSubmit.main(SparkSubmit.scala)

该报错属于Java SPI服务加载失败，核心原因是Hadoop相关依赖版本不一致/类加载冲突：
JVM通过ServiceLoader加载org.apache.hadoop.security.token.TokenIdentifier的实现类时，扫描到了高版本hadoop-yarn包注册的DockerCredentialTokenIdentifier实现，但当前classpath下不存在该类，直接触发ServiceConfigurationError。
常见触发场景：

• 应用引入的hadoop-common、hadoop-hdfs、hadoop-yarn系列依赖版本不匹配
• Tomcat容器全局lib目录与应用WEB-INF/lib目录下存在多版本Hadoop jar包，类加载时出现版本错乱
• Spark任务使用的内置Hadoop版本与集群实际运行的Hadoop版本不一致
• 打包时将scope为provided的Hadoop依赖打入应用包，和集群环境提供的Hadoop依赖产生版本冲突

• 对齐所有Hadoop核心依赖版本，确保hadoop-common、hadoop-hdfs、hadoop-yarn-api、hadoop-yarn-common等包的版本与集群运行的Hadoop版本完全一致
• Tomcat部署场景排查类加载冲突：删除Tomcat全局lib目录下与应用重复、版本不匹配的Hadoop依赖；Maven/Gradle构建时将集群已提供的Hadoop依赖scope设置为provided，避免打包时带入不匹配的私有依赖
• Spark任务场景确认Spark编译绑定的Hadoop版本与集群匹配，提交任务时可通过--jars参数指定和集群版本一致的Hadoop依赖包，优先使用集群提供的Hadoop依赖路径
• 临时验证可排查classpath下META-INF/services/org.apache.hadoop.security.token.TokenIdentifier服务配置文件，删除其中无对应实现类的org.apache.hadoop.yarn.security.DockerCredentialTokenIdentifier配置行，该方案仅用于临时调试，生产环境必须通过对齐依赖版本解决

内容的提问来源于stack exchange，提问作者Sanjay Ishwar