env

Load environment variables into Go types, with fallback values.

This package is meant to be used when configuring a twelve-factor app.

Currently supported types are bool, []byte, time.Duration, float64, int, string, []string and *url.URL

Installation

go get -u github.com/peterhellberg/env

Feel free to copy all or parts of this package into your own codebase.

Usage

package main

import (
	"fmt"

	"github.com/peterhellberg/env"
)

func main() {
	fmt.Println(
		env.Bool("BOOL", false),
		env.Bytes("BYTES", []byte{4, 2}),
		env.Duration("DURATION", 250000),
		env.Float64("FLOAT64", float64(2.5)),
		env.Int("INT", 1337),
		env.String("STRING", "Foobar"),
		env.Strings("STRINGS", []string{"Foo", "Bar"}),
		env.URL("URL", &url.URL{Scheme: "http", Host: "example.com"}),
	)
}

$ go run example.go
false [4 2] 250µs 2.5 1337 Foobar [Foo Bar] http://example.com

$ BOOL=true BYTES=foo DURATION=24m FLOAT64=11.2 INT=2600 STRING=hello STRINGS=a,b URL=http://c7.se/ go run example.go
true [102 111 111] 24m0s 11.2 2600 hello [a b] http://c7.se/

License (MIT)

Copyright (c) 2015-2023 Peter Hellberg

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.