@VisibleForTesting
  public List<FileTemplate> getDirect() {
    return ImmutableList.copyOf(direct);
  }
Return JSON representation of the SyncMap.

@return the json string representation of this SyncMap
@throws IOException if json serialization fails
jib-plugins-common/src/main/java/com/google/cloud/tools/jib/plugins/common/SkaffoldSyncMapTemplate.java