getpass – a Go module to get a password
The getpass module provides a simple way to retrieve a password from
the user by specifying a number of different password sources:
func Getpass(passfrom string) (pass string, err error)
Getpass retrieves a password from the user using a method defined by
the passfrom string. The following methods are supported:
cmd:command — Obtain the password by running the given command. The
command will be passed to the shell for execution via /bin/sh -c 'command'.
env:var — Obtain the password from the environment variable var.
Since the environment of other processes may be visible
via e.g. ps(1), this option should be used with caution.
file:pathname — The first line of pathname is the password.
pathname need not refer to a regular file: it could for example refer
to a device or named pipe. pathname undergoes standard “~” and
environment variable expansion. Note that standard Unix file access
controls should be used to protect this file.
keychain:name — Use the security(1) utility to retrieve the
password from the macOS keychain.
lpass:name — Use the LastPass command-line client lpass(1) to
retrieve the named password. You should previously have run lpass login for this to work.
op:name — Use the 1Password command-line client op(1) to retrieve
the named password.
pass:password — The actual password is password. Since the
password is visible to utilities such as ps(1) and possibly leaked
into the shell history file, this form should only be used where
security is not important.
tty — This is the default: Getpass will prompt the user on
the controlling tty using the provided prompt. If no prompt is
provided, then Getpass will use “Password: “.
Examples
package main
import (
"flag"
"fmt"
"log"
"github.com/jschauma/getpass"
)
func main() {
var pass string
flag.StringVar(&pass, "p", "tty", "password method")
flag.Parse()
// Try out any of the options:
p, err := getpass.Getpass(pass)
if err != nil {
log.Fatal("Unable to get password from user: ", err)
} else {
fmt.Printf("%s\n", p)
}
// Alternatively:
// This will prompt the user to enter a password interactively,
// using the default prompt.
p, err = getpass.Getpass()
if err != nil {
log.Fatal("Unable to get password from user: ", err)
} else {
fmt.Printf("%s\n", p)
}
// Using a custom prompt:
p, err = getpass.Getpass("tty:Please enter your secret passphrase: ")
if err != nil {
log.Fatal("Unable to get password from user: ", err)
} else {
fmt.Printf("%s\n", p)
}
// Using an environment variable:
p, err = getpass.Getpass("env:MYSECRET")
if err != nil {
log.Fatal("Unable to get password from user: ", err)
} else {
fmt.Printf("%s\n", p)
}
// Using a file:
p, err = getpass.Getpass("file:~/.secret")
if err != nil {
log.Fatal("Unable to get password from user: ", err)
} else {
fmt.Printf("%s\n", p)
}
// etc. etc.
}
