# Building from Source

While building, you must point the environment variable PORTAL_HOME to the root directory containing the portal source code.

For example, run a command like the following if on macOS:

export PORTAL_HOME=/Users/ecerami/dev/cbioportal

To compile the cBioPortal source code, move into the source directory and run the following maven command:

mvn -DskipTests clean install

After this command completes, you will find a cbioportal.war file suitable for Apache Tomcat deployment in portal/target/. It is not neccessary to install Tomcat yourself, since a command line runnable version of Tomcat is provided as a dependency in portal/target/dependency/webapp-runner.jar.

However, if you will be deploying to a standalone Tomcat installation, and if you have configured Tomcat to use the Redisson client for user session management, you should expect a clash between the Redisson client being used for session management and the Redisson client which is embedded in the cbioportal.war file for the optional "redis" persitence layer caching mode. In this case, you should avoid using the "redis" option for the portal property persistence.cache_type and you should prevent the Redisson client from being packaged in cbioportal.war by building with this command instead:

mvn -Dexclude-redisson -DskipTests clean install