func getSigningKey(credentials Credentials, option *SignOption) string {
var authStringPrefix = fmt.Sprintf("bce-auth-v1/%s", credentials.AccessKeyID)
authStringPrefix += "/" + option.Timestamp
authStringPrefix += "/" + strconv.Itoa(option.ExpirationPeriodInSeconds)
return util.HmacSha256Hex(credentials.SecretAccessKey, authStringPrefix)
}
// sign returns signed signature.
func sign(credentials Credentials, req Request, option *SignOption) string {
signingKey := getSigningKey(credentials, option)
req.prepareHeaders(option)
canonicalRequest := req.canonical(option)
signature := util.HmacSha256Hex(signingKey, canonicalRequest)
return signature
}