Env makes it easy to get your environment variables in the correct typed format. It also introduces a fallback system in case the environmen variable is not set or is not valid for the requested type.
Have a look at the available methods in the documentation.
Notifiers can be used to take action when something goes wrong. This could be when an environment variabe isn't set or when it doesn't match what we expect it to be, for example when parsing durations.
There are several implementations of notifiers, the most basic one being the
nilNotifier which does nothing with the notifications.
Another implementation is the panicNotifier, which will panic when
notifications happen, terminating the application.
import (
"github.com/jelmersnoeck/env"
)
func main() {
os.Setenv("MY_ENV", "5s") // do this on launching your application
time.Sleep(env.Duration("MY_ENV", time.Second)) // this will sleep for 5 seconds
time.Sleep(env.Duration("MY_OTHER_ENV", time.Second)) // this will sleep for a second
os.Setenv("WRONG_ENV", "hello")
time.Sleep(env.Duration("WRONG_ENV", time.Minute)) // this will sleep for a minute
}import (
"github.com/jelmersnoeck/env"
"github.com/jelmersnoeck/env/notifier/panic"
)
func main() {
env.UseNotifier(panic.NewNotifier())
os.Setenv("MY_ENV", "5s") // do this on launching your application
time.Sleep(env.Duration("MY_ENV", time.Second)) // this will sleep for 5 seconds
time.Sleep(env.Duration("MY_OTHER_ENV", time.Second)) // this will panic because the env is not set
os.Setenv("WRONG_ENV", "hello")
time.Sleep(env.Duration("WRONG_ENV", time.Minute)) // this will panic because the env is not a duration
}