I have a problem with appoop2.2.0 append app. I am adding some bytes to the hdfs file using the java HDFS API. First, I will create the target file if the file does not exist before adding operations, such as:
String fileUri = "hdfs://hadoopmaster:9000/in/append_test.txt";
// create the hdfs file, if not exists
HdfsClient.createPathIfNotExist(fileUri);
// do 5 times append operation
for (int i=0; i<5; i++){
HdfsClient.appendTo(fileUri, ("append content"+i).getBytes("UTF-8"));
}
Function createPathIfNotExist:
Path p = null;
FileSystem fs = null;
try {
fs = FileSystem.get(URI.create(uri), conf);
p = new Path(uri);
if (!fs.exists(p)) {
if (uri.charAt(uri.length() - 1) == '/'){
if(fs.mkdirs(p)){
}
}else{
FSDataOutputStream fos = fs.create(p);
fos.close();
}
} else{
System.out.println(uri + "existing");
}
} catch (IOException e) {
e.printStackTrace();
} finally{
if (fs != null)
try {
fs.close();
fs = null;
} catch (IOException e) {
e.printStackTrace();
}
}
Function appendTo:
ByteArrayInputStream in = null;
OutputStream out = null;
FileSystem fs = null;
try {
in = new ByteArrayInputStream(bytes);
fs = FileSystem.get(URI.create(uri), conf);
out = fs.append(new Path(uri));
IOUtils.copyBytes(in, out, bufferSize, false);
} catch(Exception e){
e.printStackTrace();
} finally{
if (in != null) IOUtils.closeStream(in);
if (out != null) IOUtils.closeStream(out);
if (fs != null){
try {
fs.close();
fs = null;
} catch (IOException e) {
e.printStackTrace();
}
}
}
As a result, append_test.txt is created, but the content contains only:
append content0
And an exception will occur:
org.apache.hadoop.ipc.RemoteException(org.apache.hadoop.hdfs.protocol.AlreadyBeingCreatedException): Failed to create file [/in/append_test.txt] for [DFSClient_NONMAPREDUCE_-1148656837_1] on client [192.168.141.1], because this file is already being created by [DFSClient_NONMAPREDUCE_2099912242_1] on [192.168.141.1]
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.recoverLeaseInternal(FSNamesystem.java:2320)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.appendFileInternal(FSNamesystem.java:2153)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.appendFileInt(FSNamesystem.java:2386)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.appendFile(FSNamesystem.java:2347)
at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.append(NameNodeRpcServer.java:508)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolServerSideTranslatorPB.append(ClientNamenodeProtocolServerSideTranslatorPB.java:320)
at org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos$ClientNamenodeProtocol$2.callBlockingMethod(ClientNamenodeProtocolProtos.java:59572)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:585)
at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:928)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2048)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2044)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1491)
at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2042)
at org.apache.hadoop.ipc.Client.call(Client.java:1347)
at org.apache.hadoop.ipc.Client.call(Client.java:1300)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:206)
at com.sun.proxy.$Proxy10.append(Unknown Source)
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.apache.hadoop.io.retry.RetryInvocationHandler.invokeMethod(RetryInvocationHandler.java:186)
at org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:102)
at com.sun.proxy.$Proxy10.append(Unknown Source)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolTranslatorPB.append(ClientNamenodeProtocolTranslatorPB.java:245)
at org.apache.hadoop.hdfs.DFSClient.callAppend(DFSClient.java:1480)
at org.apache.hadoop.hdfs.DFSClient.append(DFSClient.java:1520)
at org.apache.hadoop.hdfs.DFSClient.append(DFSClient.java:1508)
at org.apache.hadoop.hdfs.DistributedFileSystem$4.doCall(DistributedFileSystem.java:310)
at org.apache.hadoop.hdfs.DistributedFileSystem$4.doCall(DistributedFileSystem.java:306)
at org.apache.hadoop.fs.FileSystemLinkResolver.resolve(FileSystemLinkResolver.java:81)
at org.apache.hadoop.hdfs.DistributedFileSystem.append(DistributedFileSystem.java:306)
at org.apache.hadoop.fs.FileSystem.append(FileSystem.java:1160)
at org.lh.blog.message.hadoop.HdfsClient$2.run(HdfsClient.java:130)
at org.lh.blog.message.hadoop.HdfsClient$2.run(HdfsClient.java:1)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:356)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1471)
at org.lh.blog.message.hadoop.HdfsClient.appendTo(HdfsClient.java:121)
at org.lh.blog.message.hadoop.HdfsClient.appendTo(HdfsClient.java:110)
at org.lh.blog.message.test.HdfsClientTests.testCreateFileBeforeAppend(HdfsClientTests.java:26)
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.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:45)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:42)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:263)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:68)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:47)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:231)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:60)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:229)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:50)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:222)
at org.junit.runners.ParentRunner.run(ParentRunner.java:300)
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)
This suggests that he only added an operation once after creating a non-experiment file, the other 4 addition operations were not performed, errors occur above. I created the file before adding, but it says AlreadyBeingCreatedExceptionI'm a bit confused.
. hdfs, java API, . hdfs, hdfs ( .., "Hdfs dfs -put" ), .
, ?
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