func()

in notify/email/email.go [73:123]

• 46 lines of code
• 12 McCabe index (conditional complexity)

func (n *Email) auth(mechs string) (smtp.Auth, error) {
	username := n.conf.AuthUsername

	// If no username is set, keep going without authentication.
	if n.conf.AuthUsername == "" {
		level.Debug(n.logger).Log("msg", "smtp_auth_username is not configured. Attempting to send email without authenticating")
		return nil, nil
	}

	err := &types.MultiError{}
	for _, mech := range strings.Split(mechs, " ") {
		switch mech {
		case "CRAM-MD5":
			secret := string(n.conf.AuthSecret)
			if secret == "" {
				err.Add(errors.New("missing secret for CRAM-MD5 auth mechanism"))
				continue
			}
			return smtp.CRAMMD5Auth(username, secret), nil

		case "PLAIN":
			password, passwordErr := n.getPassword()
			if passwordErr != nil {
				err.Add(passwordErr)
				continue
			}
			if password == "" {
				err.Add(errors.New("missing password for PLAIN auth mechanism"))
				continue
			}
			identity := n.conf.AuthIdentity

			return smtp.PlainAuth(identity, username, password, n.conf.Smarthost.Host), nil
		case "LOGIN":
			password, passwordErr := n.getPassword()
			if passwordErr != nil {
				err.Add(passwordErr)
				continue
			}
			if password == "" {
				err.Add(errors.New("missing password for LOGIN auth mechanism"))
				continue
			}
			return LoginAuth(username, password), nil
		}
	}
	if err.Len() == 0 {
		err.Add(errors.New("unknown auth mechanism: " + mechs))
	}
	return nil, err
}