public async Task <bool> AddRefreshToken(RefreshToken token)
{
var existingToken = _ctx.RefreshTokens.Where(r => r.Subject == token.Subject && r.ClientId == token.ClientId).SingleOrDefault();
if (existingToken != null)
{
var result = await RemoveRefreshToken(existingToken);
}
_ctx.RefreshTokens.Add(token);
return(await _ctx.SaveChangesAsync() > 0);
}
