Small lib to avoid boiler plate code around environment variables.

import "github.com/spider-pigs/envlookup"

Set some environment variables:

export JAZZ_ARTIST="John Coltrane"
export PLAYED_WITH_MILES_DAVIES=true
export NO_OF_STUDIO_ALBUMS="51"
export RECORD_LABELS="Impulse!,Atlantic,Prestige,Blue Note"
export LONGEST_RECORDED_TRACK="27m32s"

Get an env var value. If the value does not exist, an error will be returned:

s, err := envlookup.String("JAZZ_ARTIST")

Get an env var value or a default value if it does not exist:

s, err := envlookup.String("JAZZ_SAXOPHONIST", "Wayne Shorter")

There are must helper functions for mandatory env vars (panics if err is non-nil):

s := envlookup.MustString(envlookup.String("JAZZ_SAXOPHONIST"))

To get values as a slice (comma-separated string):

s, err := envlookup.Slice("RECORD_LABELS")

Boolean values are supported:

b, err := envlookup.Bool("PLAYED_WITH_MILES_DAVIES")

Get float (64 bit) or int envs:

i, err := envlookup.Int("NO_OF_STUDIO_ALBUMS")

To get a duration value:

d, err := envlookup.Duration("LONGEST_RECORDED_TRACK")

If an env var is not set (and there is no default value set), a NotFoundError will be returned:

d, err := envlookup.Duration("LONGEST_ALBUM")
if _, ok := err.(*envlookup.NotFoundError); ok {
    log.Println(err)
    // could not find environment variable "LONGEST_ALBUM"
    ...
}

If an env var can not be parsed as the expected return type, a ParseError will be returned:

f, err := envlookup.Float64("LONGEST_RECORDED_TRACK")
if _, ok := err.(*envlookup.ParseError); ok {
    log.Println(err)
    // could not parse environment variable "LONGEST_RECORDED_TRACK": strconv.ParseFloat: parsing "27m32s": invalid syntax
    ...
}