Mining Component Repositories for Installability Issues

Component repositories play an increasingly relevant role in software life-cycle management, from software distribution to end-user, to deployment and upgrade management. Software components shipped via such repositories are equipped with rich metadata that describe their relationship (e.g., dependencies and conflicts) with other components. In this practice paper we show how to use a tool, distcheck, that uses component metadata to identify all the components in a repository that cannot be installed (e.g., due to unsatisfiable dependencies), provides detailed information to help developers understanding the cause of the problem, and fix it in the repository. We report about detailed analyses of several repositories: the Debian distribution, the OPAM package collection, and Drupal modules. In each case, distcheck is able to efficiently identify not installable components and provide valuable explanations of the issues. Our experience provides solid ground for generalizing the use of distcheck to other component repositories.