sustainyfacts.dev/anyconfig

AnyConfig

With a single line of code, bring flexible configuration for to command line utilities or microservices.

Requires Go 1.22 or newer.

Features

• ✅ Configuration struct: one struct to rule them all: define a single struct to hold all your configuration, its validation and documentation.
• ✅ Environment variables: automatically bind your configuration from environment variables using Envconfig.
• ✅ File configuration: read your configuration from a JSON or YAML file. Useful for command-line utilities that need a persistent configuration.
• ✅ Validation: Define simple validation rules for your configuration using Validator.
• ✅ Defaults: provide clever defaults for your configuration

Notes: this is a very simple wrapper around Envconfig, and most of the features provide this library and json/yaml unmarshallers.

Usage

Simple example

package main

import (
    "log"
    
    "sustainyfacts.dev/anyconfig"
)

func main() {
  var conf struct {
    Port int    `env:"PORT"`
    Host string `env:"USERNAME"`
  }

  if err := anyconfig.Read(&conf); err != nil {
    log.Fatal(err)
  }
}

Complex example

package main

import (
    "log"
    
    "sustainyfacts.dev/anyconfig"
)

// Configuration
type Config struct {
  Server struct {
    Port     int    `env:"PORT" validate:"gte=0"`
    Hostname string `json:"host" yaml:"host" env:"USERNAME" validate:"hostname"`
  } `env:", prefix=SERVER_"`
  Logging struct {
    Environment string `json:"env" yaml:"env" env:"ENV, overwrite" validate:"oneof=prod staging dev"`
    Level       string `env:"LEVEL" validate:"oneof=debug info warn error"`
  } `env:", prefix=LOGGING_"`
}

func main() {
  var conf Config
  if err := anyconfig.Read(&conf, anyconfig.WithFile("conf.yaml")); err != nil {
    log.Fatal(err)
  }
}

Together with the following YAML file:

# This is am example yaml config file
server:
  host: example.com
  port: 8080
logging:
  env: dev
  level: debug

Or with the following Enviroment variables:

SERVER_HOST=example.com
SERVER_PORT=8080
LOGGING_ENV=dev
LOGGING_LEVEL=debug

For the complete reference for "env:" annotations, please refer to the project Envconfig.

License

AnyCache is released under the Apache 2.0 license (see LICENSE)