Building from Source

WSO2 invites you to contribute by downloading the source code from the GitHub source control system, building the product and making changes, and then committing your changes back to the source repository. The following sections describe this process:

Building from source is optional. Users who do not want to make changes to the source code can simply download the binary distribution of the product and install it.

Downloading the source

WSO2 products are built on top of WSO2 Carbon Kernel, which contains the Kernel libraries used by all products. When there are changes in the Carbon Kernel, they are bundled and released in a new WSO2 Carbon version (for example, WSO2 Carbon 4.3.0). You can download the complete WSO2 Kernel release using the following repository: https://github.com/wso2/carbon4-kernel, which is recommended if you intend to modify the source.

After downloading the source of the Carbon Kernel, execute the following command to download the source of the product: git clone https://github.com/wso2/product-cep

After the source code is downloaded, you can start editing. However, it is recommended to run a build prior to changing the source code to ensure that the download is complete.

Editing the source code

Now that you have downloaded the source code for the Carbon project from GitHub, you can prepare your development environment and do the required changes to the code.

To edit the source code in your IDE, set up your development environment by running one of the following commands:

IDE	Command	Additional information
Eclipse	`mvn eclipse:eclipse`	http://maven.apache.org/plugins/maven-eclipse-plugin
IntelliJ IDEA	`mvn idea:idea`	http://maven.apache.org/plugins/maven-idea-plugin

Add the required changes to the source code.

Building the product

Ensure that the following prerequisites are in place before you build:

Make sure the build server has an active Internet connection to download dependencies while building.
Install Maven and JDK. For compatible versions, see Installation Prerequisites.
Set the environment variable MAVEN_OPTS=”-Xms1024m -Xmx4096m -XX:MaxPermSize=1024m” to avoid the Maven OutOfMemoryError.

Use the following Maven commands to build your product:

Command	Description
`mvn clean install`	The binary and source distributions.
`mvn clean install -Dmaven.test.skip=true`	The binary and source distributions, without running any of the unit tests.
`mvn clean install -Dmaven.test.skip=true -o`	The binary and source distributions, without running any of the unit tests, in offline mode. This can be done only if you have already built the source at least once.

Committing your changes

You can contribute to WSO2 products by committing your changes to GitHub. Whether you are a committer or a non-committer, you can contribute with your code.