Kafka-0.8.1.1源码编译

Kafka is a distributed, partitioned, replicated commit log service. It provides the functionality of a messaging system, but with a unique design.(Kafka是一个分布式的、可分区的(partitioned)、基于备份的(replicated)和commit-log存储的服务.。它提供了类似于messaging system的特性,但是在设计实现上完全不同)。kafka是一种高吞吐量的分布式发布订阅消息系统，它有如下特性：
　　（1）、通过O(1)的磁盘数据结构提供消息的持久化，这种结构对于即使数以TB的消息存储也能够保持长时间的稳定性能。
　　（2）、高吞吐量：即使是非常普通的硬件kafka也可以支持每秒数十万的消息。
　　（3）、支持通过kafka服务器和消费机集群来分区消息。

　　（4）、支持Hadoop并行数据加载。

我们可以用Kafka里面自带的脚本进行编译；我们也可以用sbt进行编译，sbt编译有点麻烦，我将在文章的后面进行介绍。

一、用Kafka里面自带的脚本进行编译

　　下载好了Kafka源码，里面自带了一个gradlew的脚本，我们可以利用这个编译Kafka源码：

# wget http://mirror.bit.edu.cn/apache/kafka/0.8.1.1/kafka-0.8.1.1-src.tgz
# tar -zxf kafka-0.8.1.1-src.tgz
# cd kafka-0.8.1.1-src
# ./gradlew releaseTarGz

运行上面的命令进行编译将会出现以下的异常信息：

:core:signArchives FAILED

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':core:signArchives'.
> Cannot perform signing task ':core:signArchives' because it
 has no configured signatory

* Try:
Run with --stacktrace option to get the stack trace. Run with 
--info or --debug option to get more log output.

BUILD FAILED

这是一个bug（https://issues.apache.org/jira/browse/KAFKA-1297），可以用下面的命令进行编译

1
./gradlew releaseTarGzAll -x signArchives
这时候将会编译成功（在编译的过程中将会出现很多的）。在编译的过程中，我们也可以指定对应的Scala版本进行编译：

1
./gradlew -PscalaVersion=2.10.3 releaseTarGz -x signArchives
编译完之后将会在core/build/distributions/里面生成kafka_2.10-0.8.1.1.tgz文件，这个和从网上下载的一样，可以直接用。

二、利用sbt进行编译

　　我们同样可以用sbt来编译Kafka，步骤如下：

# git clone https://git-wip-us.apache.org/repos/asf/kafka.git
# cd kafka
# git checkout -b 0.8 remotes/origin/0.8
# ./sbt update
[info] 	[SUCCESSFUL ] org.eclipse.jdt#core;3.1.1!core.jar (2243ms)
[info] downloading http://repo1.maven.org/maven2/ant/ant/1.6.5/ant-1.6.5.jar ...
[info] 	[SUCCESSFUL ] ant#ant;1.6.5!ant.jar (1150ms)
[info] Done updating.
[info] Resolving org.apache.hadoop#hadoop-core;0.20.2 ...
[info] Done updating.
[info] Resolving com.yammer.metrics#metrics-annotation;2.2.0 ...
[info] Done updating.
[info] Resolving com.yammer.metrics#metrics-annotation;2.2.0 ...
[info] Done updating.
[success] Total time: 168 s, completed Jun 18, 2014 6:51:38 PM

# ./sbt package
[info] Set current project to Kafka (in build file:/export1/spark/kafka/)
Getting Scala 2.8.0 ...
:: retrieving :: org.scala-sbt#boot-scala
	confs: [default]
	3 artifacts copied, 0 already retrieved (14544kB/27ms)
[success] Total time: 1 s, completed Jun 18, 2014 6:52:37 PM

对于Kafka 0.8及以上版本还需要运行以下的命令：

# ./sbt assembly-package-dependency
[info] Loading project definition from /export1/spark/kafka/project
[warn] Multiple resolvers having different access mechanism configured with 
same name 'sbt-plugin-releases'. To avoid conflict, Remove duplicate project 
resolvers (`resolvers`) or rename publishing resolver (`publishTo`).
[info] Set current project to Kafka (in build file:/export1/spark/kafka/)
[warn] Credentials file /home/wyp/.m2/.credentials does not exist
[info] Including slf4j-api-1.7.2.jar
[info] Including metrics-annotation-2.2.0.jar
[info] Including scala-compiler.jar
[info] Including scala-library.jar
[info] Including slf4j-simple-1.6.4.jar
[info] Including metrics-core-2.2.0.jar
[info] Including snappy-java-1.0.4.1.jar
[info] Including zookeeper-3.3.4.jar
[info] Including log4j-1.2.15.jar
[info] Including zkclient-0.3.jar
[info] Including jopt-simple-3.2.jar
[warn] Merging 'META-INF/NOTICE' with strategy 'rename'
[warn] Merging 'org/xerial/snappy/native/README' with strategy 'rename'
[warn] Merging 'META-INF/maven/org.xerial.snappy/snappy-java/LICENSE' 
with strategy 'rename'
[warn] Merging 'LICENSE.txt' with strategy 'rename'
[warn] Merging 'META-INF/LICENSE' with strategy 'rename'
[warn] Merging 'META-INF/MANIFEST.MF' with strategy 'discard'
[warn] Strategy 'discard' was applied to a file
[warn] Strategy 'rename' was applied to 5 files
[success] Total time: 3 s, completed Jun 18, 2014 6:53:41 PM

当然，我们也可以在sbt里面指定scala的版本：

sbt "++2.10.3 update"
sbt "++2.10.3 package"
sbt "++2.10.3 assembly-package-dependency"