Dependency Management

Managing libraries for Cassandra is a bit less straight forward compared to other projects, as the build process is based on ant, maven and manually managed jars. Make sure to follow the steps below carefully and pay attention to any emerging issues in the Jenkins CI Environment and reported related issues on Jira/ML, in case of any project dependency changes.

As Cassandra is an Apache product, all included libraries must follow Apache’s software license requirements.

Required steps to add or update libraries

  • Add or replace jar file in lib directory
  • Add or update lib/license files
  • Update dependencies in build.xml
    • Add to parent-pom with correct version
    • Add to all-pom if simple Cassandra dependency (see below)

POM file types

  • parent-pom - contains all dependencies with the respective version. All other poms will refer to the artifacts with specified versions listed here.
  • build-deps-pom(-sources) + coverage-deps-pom - used by ant build compile target. Listed dependenices will be resolved and copied to build/lib/{jar,sources} by executing the maven-ant-tasks-retrieve-build target. This should contain libraries that are required for build tools (grammar, docs, instrumentation), but are not shipped as part of the Cassandra distribution.
  • test-deps-pom - refered by maven-ant-tasks-retrieve-test to retrieve and save dependencies to build/test/lib. Exclusively used during JUnit test execution.
  • all-pom - pom for cassandra-all.jar that can be installed or deployed to public maven repos via ant publish
  • dist-pom - pom for tarball distribution (cassandra-{bin,src}.tar.gz) created by ant artifacts. Should be left as is, but needed for installing or deploying releases.

Troubleshooting and conflict resolution

Here are some useful commands that may help you out resolving conflicts.

  • ant realclean - gets rid of the build directory, including build artifacts.
  • mvn dependency:tree -f build/apache-cassandra-*-SNAPSHOT.pom -Dverbose -Dincludes=org.slf4j - shows transitive dependency tree for artifacts, e.g. org.slf4j. In case the command above fails due to a missing parent pom file, try running ant mvn-install.
  • rm ~/.m2/repository/org/apache/cassandra/apache-cassandra/ - removes cached local Cassandra maven artifacts