Hi Stefan, Stephan,
Yes, the `hadoop.security.group.mapping` option is explicitly set to
`org.apache.hadoop.security.LdapGroupsMapping`. Guess that was why the
classloader found an unshaded class.
I don’t have the permission to change the Hadoop cluster configurations so I
modified the `core-default-shaded.xml` and marked the option as final to solve
the problem, after which the class loading exceptions were gone.
But anther problem came up (likely not related to the previous problem):
In case of the old bucketing sink (version 1.5.3), it seems that the
`org.apache.hadoop.fs.s3a.S3AFileSystem` is initiated twice before the task
starts running. The first time is called by
`org.apache.flink.fs.s3hadoop.S3FileSystemFactory` and works well, but the
second time is called by bucketing sink itself, and fails to leverage the
`s3.*` parameters like the access key and the secret key.
The stack traces are as below:
```
com.amazonaws.AmazonClientException: Unable to load AWS credentials from any
provider in the chain
at
com.amazonaws.auth.AWSCredentialsProviderChain.getCredentials(AWSCredentialsProviderChain.java:117)
at
com.amazonaws.services.s3.AmazonS3Client.invoke(AmazonS3Client.java:3521)
at
com.amazonaws.services.s3.AmazonS3Client.headBucket(AmazonS3Client.java:1031)
at
com.amazonaws.services.s3.AmazonS3Client.doesBucketExist(AmazonS3Client.java:994)
at
org.apache.hadoop.fs.s3a.S3AFileSystem.initialize(S3AFileSystem.java:297)
at
org.apache.flink.streaming.connectors.fs.bucketing.BucketingSink.createHadoopFileSystem(BucketingSink.java:1307)
at
org.apache.flink.streaming.connectors.fs.bucketing.BucketingSink.initFileSystem(BucketingSink.java:426)
at
org.apache.flink.streaming.connectors.fs.bucketing.BucketingSink.initializeState(BucketingSink.java:370)
at
org.apache.flink.streaming.util.functions.StreamingFunctionUtils.tryRestoreFunction(StreamingFunctionUtils.java:178)
at
org.apache.flink.streaming.util.functions.StreamingFunctionUtils.restoreFunctionState(StreamingFunctionUtils.java:160)
at
org.apache.flink.streaming.api.operators.AbstractUdfStreamOperator.initializeState(AbstractUdfStreamOperator.java:96)
at
org.apache.flink.streaming.api.operators.AbstractStreamOperator.initializeState(AbstractStreamOperator.java:254)
at
org.apache.flink.streaming.runtime.tasks.StreamTask.initializeState(StreamTask.java:730)
at
org.apache.flink.streaming.runtime.tasks.StreamTask.invoke(StreamTask.java:295)
at org.apache.flink.runtime.taskmanager.Task.run(Task.java:712)
at java.lang.Thread.run(Thread.java:748)
```
I haven’t figured out why the s3a filesystem needs to be initiated twice. And
is it a bug that the bucketing sink does not use filesystem factories to create
filesystem?
Thank you very much!
Best,
Paul Lam
> 在 2018年9月20日，23:35，Stephan Ewen <se...@apache.org> 写道：
>
> Hi!
>
> A few questions to diagnose/fix this:
>
> Do you explicitly configure the "hadoop.security.group.mapping"?
>
> - If not, this setting may have leaked in from a Hadoop config in the
> classpath. We are fixing this in Flink 1.7, to make this insensitive to such
> settings leaking in.
>
> - If yes, then please try setting the config variable to
> "hadoop.security.group.mapping:
> org.apache.flink.fs.s3hadoop.shaded.org.apache.hadoop.security.LdapGroupsMapping"?
>
> Please let us know if that works!
>
>
>
> On Thu, Sep 20, 2018 at 1:40 PM, Stefan Richter <s.rich...@data-artisans.com>
> wrote:
> Hi,
>
> I could not find any open Jira for the problem you describe. Could you please
> open one?
>
> Best,
> Stefan
>
> > Am 19.09.2018 um 09:54 schrieb Paul Lam <paullin3...@gmail.com>:
> >
> > Hi,
> >
> > I’m using StreamingFileSink of 1.6.0 to write logs to S3 and encounter a
> > classloader problem. It seems that there are conflicts in
> > flink-shaded-hadoop2-uber-1.6.0.jar and flink-s3-fs-hadoop-1.6.0.jar, and
> > maybe related to class loading orders.
> >
> > Did anyone meet this problem? Thanks a lot!
> >
> > The stack traces are as below:
> >
> > java.io.IOException: java.lang.RuntimeException: class
> > org.apache.hadoop.security.LdapGroupsMapping not
> > org.apache.flink.fs.s3hadoop.shaded.org.apache.hadoop.security.GroupMappingServiceProvider
> > at
> > org.apache.flink.fs.s3hadoop.shaded.org.apache.flink.runtime.fs.hdfs.AbstractFileSystemFactory.create(AbstractFileSystemFactory.java:62)
> > at
> > org.apache.flink.core.fs.FileSystem.getUnguardedFileSystem(FileSystem.java:395)
> > at org.apache.flink.core.fs.FileSystem.get(FileSystem.java:318)
> > at
> > org.apache.flink.streaming.api.functions.sink.filesystem.Buckets.<init>(Buckets.java:111)
> > at
> > org.apache.flink.streaming.api.functions.sink.filesystem.StreamingFileSink$RowFormatBuilder.createBuckets(StreamingFileSink.java:242)
> > at
> > org.apache.flink.streaming.api.functions.sink.filesystem.StreamingFileSink.initializeState(StreamingFileSink.java:327)
> > at
> > org.apache.flink.streaming.util.functions.StreamingFunctionUtils.tryRestoreFunction(StreamingFunctionUtils.java:178)
> > at
> > org.apache.flink.streaming.util.functions.StreamingFunctionUtils.restoreFunctionState(StreamingFunctionUtils.java:160)
> > at
> > org.apache.flink.streaming.api.operators.AbstractUdfStreamOperator.initializeState(AbstractUdfStreamOperator.java:96)
> > at
> > org.apache.flink.streaming.api.operators.AbstractStreamOperator.initializeState(AbstractStreamOperator.java:254)
> > at
> > org.apache.flink.streaming.runtime.tasks.StreamTask.initializeState(StreamTask.java:738)
> > at
> > org.apache.flink.streaming.runtime.tasks.StreamTask.invoke(StreamTask.java:289)
> > at org.apache.flink.runtime.taskmanager.Task.run(Task.java:711)
> > at java.lang.Thread.run(Thread.java:748)
> > Caused by: java.lang.RuntimeException: java.lang.RuntimeException: class
> > org.apache.hadoop.security.LdapGroupsMapping not
> > org.apache.flink.fs.s3hadoop.shaded.org.apache.hadoop.security.GroupMappingServiceProvider
> > at
> > org.apache.flink.fs.s3hadoop.shaded.org.apache.hadoop.conf.Configuration.getClass(Configuration.java:2246)
> > at
> > org.apache.flink.fs.s3hadoop.shaded.org.apache.hadoop.security.Groups.<init>(Groups.java:108)
> > at
> > org.apache.flink.fs.s3hadoop.shaded.org.apache.hadoop.security.Groups.<init>(Groups.java:102)
> > at
> > org.apache.flink.fs.s3hadoop.shaded.org.apache.hadoop.security.Groups.getUserToGroupsMappingService(Groups.java:450)
> > at
> > org.apache.flink.fs.s3hadoop.shaded.org.apache.hadoop.security.UserGroupInformation.initialize(UserGroupInformation.java:309)
> > at
> > org.apache.flink.fs.s3hadoop.shaded.org.apache.hadoop.security.UserGroupInformation.ensureInitialized(UserGroupInformation.java:276)
> > at
> > org.apache.flink.fs.s3hadoop.shaded.org.apache.hadoop.security.UserGroupInformation.loginUserFromSubject(UserGroupInformation.java:832)
> > at
> > org.apache.flink.fs.s3hadoop.shaded.org.apache.hadoop.security.UserGroupInformation.getLoginUser(UserGroupInformation.java:802)
> > at
> > org.apache.flink.fs.s3hadoop.shaded.org.apache.hadoop.security.UserGroupInformation.getCurrentUser(UserGroupInformation.java:675)
> > at
> > org.apache.flink.fs.s3hadoop.shaded.org.apache.hadoop.fs.s3a.S3AFileSystem.initialize(S3AFileSystem.java:177)
> > at
> > org.apache.flink.fs.s3hadoop.shaded.org.apache.flink.runtime.fs.hdfs.AbstractFileSystemFactory.create(AbstractFileSystemFactory.java:57)
> > ... 13 more
> > Caused by: java.lang.RuntimeException: class
> > org.apache.hadoop.security.LdapGroupsMapping not
> > org.apache.flink.fs.s3hadoop.shaded.org.apache.hadoop.security.GroupMappingServiceProvider
> > at
> > org.apache.flink.fs.s3hadoop.shaded.org.apache.hadoop.conf.Configuration.getClass(Configuration.java:2240)
> > ... 23 more
> >
> >
> > Best,
> > Paul Lam
> >
> >
> >
>
>
