@Override
  public DataTypes handle(GetDataTypes request) {
    Set<DataVertical> transferDataTypes = registry.getTransferDataTypes();
    if (transferDataTypes.isEmpty()) {
      monitor.severe(
          () ->
              "No transfer data types were registered in "
                  + AuthServiceProviderRegistry.class.getName());
    }
    return new DataTypes(transferDataTypes);
  }
Lists the set of data types that support both import and export.
portability-api/src/main/java/org/datatransferproject/api/action/datatype/DataTypesAction.java