Config

Golang Configuration tool that support YAML, JSON, Shell Environment

is same as configor , but add LoadWithKey support and remove toml

Usage

config.example.yaml in ./config directory

server:
  host: 10.10.0.178
  port: 8585

redis:
  host: 10.1.0.16
  port: 6379
  db: 5

package main

import (
	"encoding/json"
	"fmt"
	"github.com/linxlib/config"
	"os"
)

type ServerConfig struct {
	Host string `yaml:"host" default:"0.0.0.0" env:"CONFIG_HOST"`
	Port string `yaml:"port" default:"8080"`
}

type RedisConfig struct {
	Host string `yaml:"host" default:"0.0.0.0"`
	Port string `yaml:"port" default:"8080"`
	DB   int    `yaml:"db" default:"0"`
}

func main() {
	//os.Setenv("CONFIG_HOST", "1.1.1.1")
	os.Setenv("CONFIG_REDIS_HOST", "1.2.1.1")
	var sc = new(ServerConfig)
	var rc = new(RedisConfig)
	err := config.LoadWithKey("server", sc, "config/config.yaml")
	if err != nil {
		return
	}
	err = config.LoadWithKey("redis", rc, "config/config.yaml")
	if err != nil {
		return
	}
	var sc1 = new(ServerConfig)
	err = config.LoadWithKey("", sc1, "config/config.yaml")
	if err != nil {
		return
	}
	bs, _ := json.MarshalIndent(sc, "", "  ")
	fmt.Println(string(bs))
	bs, _ = json.MarshalIndent(rc, "", "  ")
	fmt.Println(string(bs))
	bs, _ = json.MarshalIndent(sc1, "", "  ")
	fmt.Println(string(bs))

}

With configuration file config.yml:

appname: test

db:
    name:     test
    user:     test
    password: test
    port:     1234

contacts:
- name: i test
  email: [email protected]

Debug Mode & Verbose Mode

Debug/Verbose mode is helpful when debuging your application, debug mode will let you know how config loaded your configurations, like from which file, shell env, verbose mode will tell you even more, like those shell environments config tried to load.

// Enable debug mode or set env `CONFIG_DEBUG_MODE` to true when running your application
config.New(&config.Config{Debug: true}).Load(&Config, "config.json")

// Enable verbose mode or set env `CONFIG_VERBOSE_MODE` to true when running your application
config.New(&config.Config{Verbose: true}).Load(&Config, "config.json")

Auto Reload Mode

Config can auto reload configuration based on time

// auto reload configuration every second
config.New(&config.Config{AutoReload: true}).Load(&Config, "config.json")

// auto reload configuration every minute
config.New(&config.Config{AutoReload: true, AutoReloadInterval: time.Minute}).Load(&Config, "config.json")

Auto Reload Callback

config.New(&config.Config{AutoReload: true, AutoReloadCallback: func(config interface{}) {
    fmt.Printf("%v changed", config)
}}).Load(&Config, "config.json")

Advanced Usage

• Load multiple configurations

// Earlier configurations have higher priority
config.Load(&Config, "application.yml", "database.json")

• Load configuration by environment

Use CONFIG_ENV to set environment, if CONFIG_ENV not set, environment will be development by default, and it will be test when running tests with go test

// config.go
config.Load(&Config, "config.json")

$ go run config.go
// Will load `config.json`, `config.development.json` if it exists
// `config.development.json` will overwrite `config.json`'s configuration
// You could use this to share same configuration across different environments

$ CONFIG_ENV=production go run config.go
// Will load `config.json`, `config.production.json` if it exists
// `config.production.json` will overwrite `config.json`'s configuration

$ go test
// Will load `config.json`, `config.test.json` if it exists
// `config.test.json` will overwrite `config.json`'s configuration

$ CONFIG_ENV=production go test
// Will load `config.json`, `config.production.json` if it exists
// `config.production.json` will overwrite `config.json`'s configuration

// Set environment by config
config.New(&config.Config{Environment: "production"}).Load(&Config, "config.json")

• Example Configuration

// config.go
config.Load(&Config, "config.yml")

$ go run config.go
// Will load `config.example.yml` automatically if `config.yml` not found and print warning message

• Load From Shell Environment

$ CONFIG_APPNAME="hello world" CONFIG_DB_NAME="hello world" go run config.go
// Load configuration from shell environment, it's name is {{prefix}}_FieldName

// You could overwrite the prefix with environment CONFIG_ENV_PREFIX, for example:
$ CONFIG_ENV_PREFIX="WEB" WEB_APPNAME="hello world" WEB_DB_NAME="hello world" go run config.go

// Set prefix by config
config.New(&config.Config{ENVPrefix: "WEB"}).Load(&Config, "config.json")

• Anonymous Struct

Add the anonymous:"true" tag to an anonymous, embedded struct to NOT include the struct name in the environment variable of any contained fields. For example:

type Details struct {
	Description string
}

type Config struct {
	Details `anonymous:"true"`
}

With the anonymous:"true" tag specified, the environment variable for the Description field is CONFIG_DESCRIPTION. Without the anonymous:"true"tag specified, then environment variable would include the embedded struct name and be CONFIG_DETAILS_DESCRIPTION.

• With flags

func main() {
	conf := flag.String("file", "config.yml", "configuration file")
	flag.StringVar(&Config.APPName, "name", "", "app name")
	flag.StringVar(&Config.DB.Name, "db-name", "", "database name")
	flag.StringVar(&Config.DB.User, "db-user", "root", "database user")
	flag.Parse()

	os.Setenv("CONFIG_ENV_PREFIX", "-")
	config.Load(&Config, *conf)
	// config.Load(&Config) // only load configurations from shell env & flag
}

License

Released under the MIT License