public static String getExternalConfigActivationProperty(MavenProject project) {
        Properties properties = EnvUtil.getPropertiesWithSystemOverrides(project);
        String value = properties.getProperty(EXTERNALCONFIG_ACTIVATION_PROPERTY);

        // This can be used to disable in a more "local" context, if set globally
        if(PropertyMode.Skip.name().equalsIgnoreCase(value)) {
            return null;
        }

        return value;
    }
Resolve image with an external image resolver

@param images the original image config list (can be null)
@param imageResolver the resolver used to extend on an image configuration
@param imageNameFilter filter to select only certain image configurations with the given name
@param imageCustomizer final customization hook for mangling the configuration
@return a list of resolved and customized image configuration.
src/main/java/io/fabric8/maven/docker/config/ConfigHelper.java