adder

A lightweight configuration library for Go, inspired by viper.

Adder reads YAML config files and unmarshals them into Go structs, with support for environment variable overrides.

Installation

go get github.com/lwlee2608/adder

Quick Start

# application.yaml
server:
  host: localhost
  port: 8080

type Config struct {
    Server struct {
        Host string
        Port uint
    }
}

adder.SetConfigName("application")
adder.AddConfigPath(".")
adder.SetConfigType("yaml")

if err := adder.ReadInConfig(); err != nil {
    panic(err)
}

var config Config
if err := adder.Unmarshal(&config); err != nil {
    panic(err)
}

Features

• Case-insensitive YAML key matching
• YAML configuration with multiple search paths
• Automatic environment variable overrides via AutomaticEnv()
• Explicit env var binding via BindEnv()
• mapstructure struct tags for custom field mapping
• Singleton and instance-based usage

Examples

See the example/ directory:

• basic — Load config from a YAML file
• env-override — Override config values with environment variables
• bind-env — Bind config keys to specific env var names

License

MIT