Contributor Tools

IDE

We recommend using either Eclipse or IntelliJ IDEA to contribute to Alluxio. You can generate an Eclipse configuration file by running:

mvn clean -Pdeveloper install -DskipTests
mvn clean -Pdeveloper -DskipTests eclipse:eclipse -DdownloadJavadocs=true -DdownloadSources=true

Then import the folder into Eclipse.

You may also have to add the classpath variable M2_REPO by running:

mvn -Declipse.workspace="your Eclipse Workspace" eclipse:configure-workspace

If you are using IntelliJ IDEA, you may need to change the Maven profile to ‘developer’ in order to avoid import errors. You can do this by going to

View > Tool Windows > Maven Projects

Maven Targets and Plugins

Before pushing changes or submitting pull requests we recommend running various maven targets on your local machine to make sure your changes do not break existing behavior.

For these maven commands we’ll assume that your command terminal is located in the root directory of your locally cloned copy of the Alluxio repository.

cd ${ALLUXIO_HOME}

Checkstyle

To make sure your code follows our style conventions you may run. Note that this is run any time you run targets such as compile, install, or test.

mvn checkstyle:checkstyle

FindBugs

Before submitting the pull-request, run the latest code against the findbugs Maven plugin to verify no new warnings are introduced.

mvn compile findbugs:findbugs

Compilation

To simply compile the code you can run the following command:

mvn clean compile -DskipTests

This will not execute any unit tests but will execute the checkstyle, findbugs, and other plugins.

To speed up compilation you may use the command:

mvn -T 2C compile -DskipTests -Dmaven.javadoc.skip -Dfindbugs.skip -Dcheckstyle.skip -Dlicense.skip

This command will skip many of our checks that are in place to help keep our code neat. We recommend running all checks before committing.

You may replace the compile target in the above command with any other valid target to skip checks as well. The targets install, verify, and compile will be most useful.

Creating a Local Install

If you want to test your changes with a compiled version of the repository, you may generate the jars with the Maven install target.

mvn install -DskipTests

After the install target executes, you may configure and start a local cluster with the following commands:

If you haven’t configured or set up a local cluster yet, run the following commands

cp conf/alluxio-site.properties.template conf/alluxio-site.properties
echo "alluxio.master.hostname=localhost" >> conf/alluxio-site.properties
./bin/alluxio format

Once you’ve run those configuration steps you can start a local Alluxio instance with

./bin/alluxio-start.sh local SudoMount

Unit Tests

• Run all unit and integration tests

cd ${ALLUXIO_HOME}
mvn test

This will use the local filesystem as the under storage.

• Run a single unit test:

mvn -Dtest=AlluxioFSTest#createFileTest -DfailIfNoTests=false test

• To run unit tests for a specific module, execute the maven test command targeting the desired submodule directory. For example, to run tests for HDFS UFS module you would run

mvn test -pl underfs/hdfs

Run unit tests for HDFS UFS module with a different Hadoop version:

# build and run test on HDFS under storage module for Hadoop 2.7.0
mvn test -pl underfs/hdfs -Phadoop-2 -Dhadoop.version=2.7.0
# build and run test on HDFS under storage module for Hadoop 3.0.0
mvn test -pl underfs/hdfs -Phadoop-3 -Dhadoop.version=3.0.0

The above unit tests will create a simulated HDFS service with the specific version. To run more comprehensive tests on HDFS under storage using a real and running HDFS deployment:

mvn test -pl underfs/hdfs -PufsContractTest -DtestHdfsBaseDir=hdfs://ip:port/alluxio_test

• To have the logs output to STDOUT, append the following arguments to the mvn command

-Dtest.output.redirect=false -Dalluxio.root.logger=DEBUG,CONSOLE

• To quickly test the working of some APIs in an interactive manner, you may leverage the Scala shell, as discussed in this blog.

• The fuse tests are ignored if the libfuse library is missing. To run those tests, please install the correct libraries mentioned in this page.

Modifying a Thrift RPC definition

Alluxio uses Thrift 0.9.3 for RPC communication between clients and servers. The .thrift files defined in core/common/src/thrift/ are used to auto-generate Java code for calling the RPCs on clients and implementing the RPCs on servers. To change a Thrift definition, you must first install the Thrift compiler. If you have brew, you can do this by running

brew install thrift@0.9
brew link --force thrift@0.9

Then to regenerate the Java code, run

bin/alluxio thriftGen

Modifying a Protocol Buffer Message

Alluxio uses Protocol Buffers 2.5.0 to read and write journal messages. The .proto files defined in core/protobuf/src/proto/ are used to auto-generate Java definitions for the protocol buffer messages. To change one of these messages, first read about updating a message type to make sure your change will not break backwards compatibility. Next, install protoc. If you have brew, you can do this by running

brew install protobuf@2.5
brew link --force protobuf@2.5

Then to regenerate the Java code, run

bin/alluxio protoGen

Usage of ./bin/alluxio

Most commands in bin/alluxio are for developers. The following table explains the description and the syntax of each command.

In addition, these commands have different prerequisites. The prerequisite for the format, formatWorker, journalCrashTest, readJournal, version, validateConf and validateEnv commands is that you have already built Alluxio (see Build Alluxio Master Branch about how to build Alluxio manually). Further, the prerequisite for the fs, loadufs, logLevel, runTest and runTests commands is that you have a running Alluxio system.