core/src/main/java/io/fabric8/maven/core/util/kubernetes/ServiceUrlUtil.java
private static String serviceToPortOrBlank(String serviceName) {
        String envVarName = toServicePortEnvironmentVariable(serviceName);
        return getEnvVarOrSystemProperty(envVarName, "");
    }
private static String serviceToPortOrBlank(String serviceName) {
        String envVarName = toServicePortEnvironmentVariable(serviceName);
        return getEnvVarOrSystemProperty(envVarName, "");
    }
Returns the named port for the given service name or blank