0301taildir-source报错-flume-大数据

1 基础环境简介

linux系统：centos，前置安装：jdk、hadoop、zookeeper、kafka，版本如下

软件	版本	描述
centos	7	linux系统发行版
jdk	1.8	java开发工具集
hadoop	2.10.0	大数据生态基础组件
zookeeper	3.5.7	分布式应用程序协调服务
kafka	3.0	分布式mq组件
flume	1.9.0	分布式采集传输组件

2 报错

场景1：动态监控目录多个日志变化，通过flume采集传输到kafka

报错日志

org.apache.flume.FlumeException: Error creating positionFile parent directoriesat org.apache.flume.source.taildir.TaildirSource.configure(TaildirSource.java:170)at org.apache.flume.conf.Configurables.configure(Configurables.java:41)at org.apache.flume.node.AbstractConfigurationProvider.loadSources(AbstractConfigurationProvider.java:325)at org.apache.flume.node.AbstractConfigurationProvider.getConfiguration(AbstractConfigurationProvider.java:105)at org.apache.flume.node.PollingPropertiesFileConfigurationProvider$FileWatcherRunnable.run(PollingPropertiesFileConfigurationProvider.java:145)at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308)at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180)at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294)at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)at java.lang.Thread.run(Thread.java:750)
Caused by: java.nio.file.FileAlreadyExistsException: /export/server/flumeat sun.nio.fs.UnixException.translateToIOException(UnixException.java:88)at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:102)at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:107)at sun.nio.fs.UnixFileSystemProvider.createDirectory(UnixFileSystemProvider.java:384)at java.nio.file.Files.createDirectory(Files.java:674)at java.nio.file.Files.createAndCheckIsDirectory(Files.java:781)at java.nio.file.Files.createDirectories(Files.java:727)at org.apache.flume.source.taildir.TaildirSource.configure(TaildirSource.java:168)... 11 more

conf文件如下

#定义组件
a1.sources = r1
a1.channels = c1#配置source
a1.sources.r1.type = TAILDIR
a1.sources.r1.filegroups = f1
a1.sources.r1.filegroups.f1 = /opt/module/applog/log/app.*
a1.sources.r1.positionFile = /export/server/flume/taildir_position.json#配置channel
a1.channels.c1.type = org.apache.flume.channel.kafka.KafkaChannel
a1.channels.c1.kafka.bootstrap.servers = node1:9092,node2:9092
a1.channels.c1.kafka.topic = topic_log01
a1.channels.c1.parseAsFlumeEvent = false#组装 
a1.sources.r1.channels = c1

原因就是在创建positionFile的时候父目录已存在
场景2：我们生成的日志文件app.log 每经过一天会按照日期重命名文件，然后生成新的app.log,此时flume会重新采集所有的日志信息，导致信息重复采集2次。
Taildir 说明： Taildir Source 维护了一个 json 格式的 position File，其会定期的往 position File中更新每个文件读取到的最新的位置，因此能够实现断点续传。Position File 的格式如下：
```
{"inode":2496272,"pos":12,"file":"/opt/module/flume/files/file1.txt"}{"inode":2496275,"pos":12,"file":"/opt/module/flume/files2/log.txt"}
```
而flume会同时判断Inode和file来确定是否同一文件

注：Linux 中储存文件元数据的区域就叫做 inode，每个 inode 都有一个号码，操作系统

用 inode 号码来识别不同的文件，Unix/Linux 系统内部不使用文件名，而使用 inode 号码来

识别文件。

3 解决

场景1解决方案有两种：

既然是创建父目录已存在，我们可以吧positionFile位置重新配置。

修改源代码，我们通过源代码找下处理逻辑，下载1.9.0版本的flume源代码，官网地址：https://archive.apache.org/dist/flume/，找到TailSource 170行

 @Overridepublic synchronized void configure(Context context) {String fileGroups = context.getString(FILE_GROUPS);Preconditions.checkState(fileGroups != null, "Missing param: " + FILE_GROUPS);filePaths = selectByKeys(context.getSubProperties(FILE_GROUPS_PREFIX),fileGroups.split("\\s+"));Preconditions.checkState(!filePaths.isEmpty(),"Mapping for tailing files is empty or invalid: '" + FILE_GROUPS_PREFIX + "'");String homePath = System.getProperty("user.home").replace('\\', '/');positionFilePath = context.getString(POSITION_FILE, homePath + DEFAULT_POSITION_FILE);Path positionFile = Paths.get(positionFilePath);try {// 此处创建父目录，如果存在报错Files.createDirectories(positionFile.getParent());} catch (IOException e) {throw new FlumeException("Error creating positionFile parent directories", e);}headerTable = getTable(context, HEADERS_PREFIX);batchSize = context.getInteger(BATCH_SIZE, DEFAULT_BATCH_SIZE);skipToEnd = context.getBoolean(SKIP_TO_END, DEFAULT_SKIP_TO_END);byteOffsetHeader = context.getBoolean(BYTE_OFFSET_HEADER, DEFAULT_BYTE_OFFSET_HEADER);idleTimeout = context.getInteger(IDLE_TIMEOUT, DEFAULT_IDLE_TIMEOUT);writePosInterval = context.getInteger(WRITE_POS_INTERVAL, DEFAULT_WRITE_POS_INTERVAL);cachePatternMatching = context.getBoolean(CACHE_PATTERN_MATCHING,DEFAULT_CACHE_PATTERN_MATCHING);backoffSleepIncrement = context.getLong(PollableSourceConstants.BACKOFF_SLEEP_INCREMENT,PollableSourceConstants.DEFAULT_BACKOFF_SLEEP_INCREMENT);maxBackOffSleepInterval = context.getLong(PollableSourceConstants.MAX_BACKOFF_SLEEP,PollableSourceConstants.DEFAULT_MAX_BACKOFF_SLEEP);fileHeader = context.getBoolean(FILENAME_HEADER,DEFAULT_FILE_HEADER);fileHeaderKey = context.getString(FILENAME_HEADER_KEY,DEFAULT_FILENAME_HEADER_KEY);maxBatchCount = context.getLong(MAX_BATCH_COUNT, DEFAULT_MAX_BATCH_COUNT);if (maxBatchCount <= 0) {maxBatchCount = DEFAULT_MAX_BATCH_COUNT;logger.warn("Invalid maxBatchCount specified, initializing source "+ "default maxBatchCount of {}", maxBatchCount);}if (sourceCounter == null) {sourceCounter = new SourceCounter(getName());}}

在这里插入图片描述

可以在创建父目录之前检测是否已存在，如果已存在，直接跳过创建即可，修改try代码块中内容如下

boolean exists = Files.exists(positionFile.getParent());if (!exists)Files.createDirectories(positionFile.getParent());

maven打包替换flume/lib/下 flume-taildir-source-1.9.0.jar 如图所示：在这里插入图片描述

重新运行，正常启动，如下图日志所示：在这里插入图片描述

kafka中新接收的数据如下图所示：在这里插入图片描述

场景2解决方案把TailFile如下代码

  public boolean updatePos(String path, long inode, long pos) throws IOException {if (this.inode == inode && this.path.equals(path)) {setPos(pos);updateFilePos(pos);logger.info("Updated position, file: " + path + ", inode: " + inode + ", pos: " + pos);return true;}return false;}// 修改为public boolean updatePos(String path, long inode, long pos) throws IOException {if (this.inode == inode) {setPos(pos);updateFilePos(pos);logger.info("Updated position, file: " + path + ", inode: " + inode + ", pos: " + pos);return true;}return false;}