private static async Task CreateToken(
            HttpContext context,
            IdentityServerTokenRequest request,
            IdentityServerTools identityServerTools)
        {
            var token = await identityServerTools.IssueJwtAsync(
                lifetime : request.Lifetime,
                claims : request.Claims);

            var response = new IdentityServerTokenResponse
            {
                Token = token,
            };

            await context.Response.WriteJsonAsync(response);
        }
        private static async Task CreateClientToken(
            HttpContext context,
            IdentityServerClientTokenRequest request,
            IdentityServerTools identityServerTools)
        {
            var token = await identityServerTools.IssueClientJwtAsync(
                lifetime : request.Lifetime,
                clientId : request.ClientId,
                scopes : request.Scopes,
                audiences : request.Audiences);

            var response = new IdentityServerTokenResponse
            {
                Token = token,
            };

            await context.Response.WriteJsonAsync(response);
        }