list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/zeromq/cmake")

find_package(ZeroMQ)

# Default to building ZeroMQ only if ZeroMQ was found.
#
# If a user enabled the cluster backend explicitly (-D ENABLE_CLUSTER_BACKEND_ZEROMQ:bool=ON),
# but ZeroMQ wasn' found, hard bail.
option(ENABLE_CLUSTER_BACKEND_ZEROMQ "Enable the ZeroMQ cluster backend" ${ZeroMQ_FOUND})

if (ENABLE_CLUSTER_BACKEND_ZEROMQ)
    if (NOT ZeroMQ_FOUND)
        message(FATAL_ERROR "ENABLE_CLUSTER_BACKEND_ZEROMQ set, but ZeroMQ library not available")
    endif ()

    add_subdirectory(zeromq)
endif ()
