Imports github.com/boombuler/barcode/qr github.com/skip2/go-qrcode github.com/boombuler/barcode github.com/dgrijalva/jwt-go golang.org/x/crypto/scrypt Standard library imports bytes crypto/rand encoding/base64 image/png crypto/aes crypto/cipher crypto/md5 encoding/binary encoding/hex fmt io io/ioutil math net/http strconv strings time