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
go get -u github.com/peterhellberg/env
Feel free to copy all or parts of this package into your own codebase.
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/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:
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