Apache Camel FTP错误

Question

我正在编写一段代码，从FTP输入路由到bean进程然后再到FTP输出。 该过程大约需要15分钟才能完成，完成后，Camel会尝试从FTP输入路径中删除输入文件。 目前FTP服务器抛出错误：

13 Jan 2015 18:21:26 DEBUG org.apache.camel.component.file.remote.FtpOperations.deleteFile - Deleting file: ../flex-brazil/Portal_Forn/request_appr/364/NF_4.txt
13 Jan 2015 18:21:26  WARN org.slf4j.helpers.MarkerIgnoringBase.warn - Error during commit. Exchange[org.apache.camel.component.file.GenericFileMessage@3207779]. Caused by: [org.apache.camel.component.file.GenericFileOperationFailedException - File operation failed: 421 Timeout (900 seconds): closing control connection.
FTP response 421 received.  Server closed connection.. Code: 421]
org.apache.camel.component.file.GenericFileOperationFailedException: File operation failed: 421 Timeout (900 seconds): closing control connection.
FTP response 421 received.  Server closed connection.. Code: 421
at org.apache.camel.component.file.remote.FtpOperations.getCurrentDirectory(FtpOperations.java:701)
at org.apache.camel.component.file.remote.FtpOperations.deleteFile(FtpOperations.java:224)
at org.apache.camel.component.file.strategy.GenericFileDeleteProcessStrategy.commit(GenericFileDeleteProcessStrategy.java:71)
at org.apache.camel.component.file.GenericFileOnCompletion.processStrategyCommit(GenericFileOnCompletion.java:124)
at org.apache.camel.component.file.GenericFileOnCompletion.onCompletion(GenericFileOnCompletion.java:80)
at org.apache.camel.component.file.GenericFileOnCompletion.onComplete(GenericFileOnCompletion.java:54)
at org.apache.camel.util.UnitOfWorkHelper.doneSynchronizations(UnitOfWorkHelper.java:100)
at org.apache.camel.impl.DefaultUnitOfWork.done(DefaultUnitOfWork.java:228)
at org.apache.camel.util.UnitOfWorkHelper.doneUow(UnitOfWorkHelper.java:61)
at org.apache.camel.processor.CamelInternalProcessor$UnitOfWorkProcessorAdvice.after(CamelInternalProcessor.java:613)
at org.apache.camel.processor.CamelInternalProcessor$UnitOfWorkProcessorAdvice.after(CamelInternalProcessor.java:581)
at org.apache.camel.processor.CamelInternalProcessor$InternalCallback.done(CamelInternalProcessor.java:240)
at org.apache.camel.processor.CamelInternalProcessor.process(CamelInternalProcessor.java:173)
at org.apache.camel.component.file.GenericFileConsumer.processExchange(GenericFileConsumer.java:401)
at org.apache.camel.component.file.remote.RemoteFileConsumer.processExchange(RemoteFileConsumer.java:99)
at org.apache.camel.component.file.GenericFileConsumer.processBatch(GenericFileConsumer.java:201)
at org.apache.camel.component.file.GenericFileConsumer.poll(GenericFileConsumer.java:165)
at org.apache.camel.impl.ScheduledPollConsumer.doRun(ScheduledPollConsumer.java:187)
at org.apache.camel.impl.ScheduledPollConsumer.run(ScheduledPollConsumer.java:114)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:304)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:178)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
Caused by: org.apache.commons.net.ftp.FTPConnectionClosedException: FTP response 421 received.  Server closed connection.
at org.apache.commons.net.ftp.FTP.__getReply(FTP.java:367)
at org.apache.commons.net.ftp.FTP.__getReply(FTP.java:294)
at org.apache.commons.net.ftp.FTP.sendCommand(FTP.java:483)
at org.apache.commons.net.ftp.FTP.sendCommand(FTP.java:608)
at org.apache.commons.net.ftp.FTP.sendCommand(FTP.java:582)
at org.apache.commons.net.ftp.FTP.pwd(FTP.java:1454)
at org.apache.commons.net.ftp.FTPClient.printWorkingDirectory(FTPClient.java:2658)
at org.apache.camel.component.file.remote.FtpOperations.getCurrentDirectory(FtpOperations.java:697)
... 25 more

有任何参数可以教Camel向FTP服务器发送Keepalive以避免这种情况吗？

Answer 1

我建议将整个过程分为两个路线：

1. Reader Route：仅从FTP服务器读取文件。
2. 进程和写入器路由：此路由处理传入消息并将响应写入FTP服务器

优点是，连接将在读取和删除后无异常关闭。 将新消息写回服务器时，将创建新连接。

当进程异步时，第一个路由只能关闭连接。 为此，您可以使用队列进行读写，例如seda或jms 。

Answer 2

您可以考虑设置更大的超时选项 - 默认值为30秒。

要将超时设置为15分钟： ftp://user@host?timeout=900000

但请记住，FTP服务器可能会关闭连接。