key is of invalid type, []byte('key') - not working

[yongDataScince]

`token := jwt.NewWithClaims(jwt.SigningMethodES256, &tokenClaims{
jwt.StandardClaims {
ExpiresAt: time.Now().Add(tockenTTL).Unix(),
IssuedAt: time.Now().Unix(),
},
user.ID,
})

signKey := []byte("kdnjsndjnd*jdnj212md")

tkn, err := token.SignedString(signKey)
return tkn, err`

Originally posted by @yongDataScince in #65 (comment)

[huanghongqing]

SigningMethodES256 ==> SigningMethodHS256