public static String getNetwork(ImageConfiguration imageConfig) {
        String network = imageConfig.getBuildConfiguration().getNetwork();
        if (network == null) {
            network = System.getProperty("docker.network.mode");
        }
        if (network == null) {
            network = System.getProperty("docker.build.network");
        }
        if(network!=null && network.isEmpty()) {
           network = null;
        }
        return network;
    }
Initialize and validate the configuration.


@param images the images to check
@param apiVersion the original API version intended to use
@param nameFormatter formatter for image names
@param log a logger for printing out diagnostic messages
@return the minimal API Docker API required to be used for the given configuration.
src/main/java/io/fabric8/maven/docker/config/ConfigHelper.java