envconf

Go library for loading configuration from the environment variables.

Installation

go get github.com/mszenfeld/envconf

Getting Started

To start working with envconf define a structure for your config and use the loader:

export HOST="localhost"
export PORT="1337"
export DEBUG="true"

package main

import (
  "log"

  "github.com/mszenfeld/envconf"
)

type Config struct {
  Host  string
  Port  int
  Debug bool
}

func main() {
  var c Config

  l := envconf.NewLoader()
  if err := l.Load(&c); err != nil {
    log.Fatal(err)
  }
}

envconf also supports environment variable prefixes:

export APP_HOST="localhost"
export APP_PORT="1337"
export APP_DEBUG="true"

package main

import (
  "log"

  "github.com/mszenfeld/envconf"
)

type Config struct {
  Host  string
  Port  int
  Debug bool
}

func main() {
  var c Config

  l := envconf.NewLoader()
  l.SetPrefix("app")
  if err := l.Load(&c); err != nil {
    log.Fatal(err)
  }
}

Tags

envconf allows you to use the following tags:

• env
• default
• required

type Config struct {
  Host  string `default:"localhost"`
  Port  int `required:"true"`
  Debug bool `env:"ENABLE_DEBUG" default:"false"`
}

env

This tag overrides the default environment variable name of the struct field.

default

The tag value will be used as a field's value if the environment variable associated with the field does not exist.

required

The available values for this tag are only "true" and "false". If field is marked as required and environment variable does not exist, loader will return an error. By default, fields are optional.

Supported Types

envconf has support for the following types:

• string
• int, int8, int16, int32, int64
• uint, uint8, uint16, uint32, uint64
• float32, float64
• bool