private IEnumerable <string> BuildSigningPayload(SigningOption options) => new List <string>
{
BuildActionMethod(options.Action),
BuildContentMD5(options.ContentMD5),
BuildContentType(options.ContentType),
BuildExpiration(options.ExpireDate),
BuilCanonicalizedResource(options.Path)
};
public string GetSignedUrl(SigningOption options)
{
ValidateOptions(options);
var signingPayloadAsString = string.Join("\n", BuildSigningPayload(options));
var encryptedBase64String = EncryptPayload(signingPayloadAsString);
return(PrepareSignedUrl(options, encryptedBase64String));
}
private string PrepareSignedUrl(SigningOption options, string signature) => new UriBuilder
{
Scheme = "https",
Host = $"{_firebaseConfiguration.StorageBaseAuthority.TrimSlashes().Replace("https://", "")}/{_credentials.GetDefaultBucket().TrimSlashes()}",
Path = options.Path.Trim().TrimSlashes(),
Query = $"GoogleAccessId={_credentials.GetServiceAccountEmail()}&Expires={BuildExpiration(options.ExpireDate)}&Signature={WebUtility.UrlEncode(signature)}"
}
.Uri.AbsoluteUri;
private void ValidateOptions(SigningOption options)
{
if (options == null)
{
throw new ArgumentNullException(nameof(options));
}
if (options.ExpireDate.ToUnixSeconds() == 0)
{
throw new ArgumentOutOfRangeException(nameof(options.ExpireDate), "ExpireDate should be reasonable value");
}
if (string.IsNullOrWhiteSpace(options.Path))
{
throw new ArgumentNullException(nameof(options.Path));
}
}