Gengine map嵌套map写法

package main

import (
    "flag"
    "fmt"
    "github.com/bilibili/gengine/engine"
    "os"
    "regexp"
)

var config struct {
    endpoint string
    image    string
}

func init() {
    flag.StringVar(&config.endpoint, "endpoint",
        "unix:/var/run/capsule8/sensor.sock",
        "Capsule8 gRPC API endpoint")

    flag.StringVar(&config.image, "image", "",
        "container image wildcard pattern to monitor")
}

var rules3 = `
rule "3" ""  salience 0
begin
    println("--------------------------")