instack-undercloud/elements/isolated-build/README.md

Build images isolated from any external sources of software.

This is necessary for doing builds in things like Koji and Brew, where only installation sources known to the build system are allowed. This element enables that by removing/blacklisting Git and Pip and disabling source repositories.

Note that this method is not perfect - it's still possible for Git or Pip to be pulled in as a dependency of another package, but since currently this requirement is on a best-effort basis this is our best effort to meet it. At some point this will be enforced by the build system itself and we won't be responsible for ensuring compliance.