config.go

package honeycast

import (
	"io/ioutil"
	"regexp"

	"github.com/imdario/mergo"
	"gopkg.in/yaml.v2"
)

type (
	Config struct {
		Token       string      `yaml:"token"`
		Template    string      `yaml:"template"`
		Proxies ProxiesConfig   `yaml:"proxies"`
	}
)

type ProxiesConfig struct {
	SSH  SSHProxyConfig   `yaml:"ssh"`
	HTTP HTTPProxyConfig  `yaml:"http"`
}

type HTTPProxyConfig struct {
	Port string `yaml:"port"`
}

type SSHProxyConfig struct {
	Key    string `yaml:"key"`
	Port   string `yaml:"port"`
	Banner string `yaml:"banner"`
}

func (pc *SSHProxyConfig) PrivateKey() (ssh.Signer, error) {
	b, err := ioutil.ReadFile(pc.Key)
	if err != nil {
		return nil, err
	}

	return ssh.ParsePrivateKey(b)
}

var DefaultConfig = Config{
	Token:     "token",
	Template:  "c1",
	Proxies: ProxiesConfig{
		HTTP: HTTPProxyConfig{
			Port:   ":8020",
		},
		SSH: SSHProxyConfig{
			Key:    "./perms/id_rsa.key",
			Port:   ":8022",
		},
	},
}

func NewConfig() (*Config, error) {
	c := DefaultConfig
	return &c, nil
}

func (c *Config) Load(file string) error {
	data, err := ioutil.ReadFile(file)
	if err != nil {
		return err
	}

	conf := Config{}
	err = yaml.Unmarshal(data, &conf)
	if err != nil {
		return err
	}

	return mergo.MergeWithOverwrite(c, conf)
}

config.yaml

template: "test"
token: test

proxies:
    http:
        port: :8080
    ssh:
        port: :8022
        key: "./perm/perms"

main.go

config, err := NewConfig()
if err != nil {
	fmt.Fprintf(os.Stdout, err.Error())
	return
}

if err := config.Load("config.yaml"); err != nil {
	fmt.Fprintf(os.Stdout, err.Error())
	return
}