/// <summary>
/// Asynchronous processing of Middleware
/// </summary>
/// <param name="context"></param>
/// <returns></returns>
public async Task Invoke(HttpContext context)
{
var checkResult = await _algorithm.CheckAsync(context);
if (checkResult.IsLimit)
{
context.Response.StatusCode = _error.HttpStatusCode;
Dictionary <string, StringValues> headers = null;
if (_error.BuildHttpHeadersAsync != null)
{
headers = await _error.BuildHttpHeadersAsync(context, checkResult).ConfigureAwait(false);
}
else if (_error.BuildHttpHeaders != null)
{
headers = _error.BuildHttpHeaders(context, checkResult);
}
if (headers != null && headers.Count > 0)
{
foreach (var h in headers)
{
context.Response.Headers.Append(h.Key, h.Value);
}
}
string content = null;
if (_error.BuildHttpContentAsync != null)
{
content = await _error.BuildHttpContentAsync(context, checkResult).ConfigureAwait(false);
}
else if (_error.BuildHttpContent != null)
{
content = _error.BuildHttpContent(context, checkResult);
}
if (!string.IsNullOrWhiteSpace(content))
{
var bodyContent = Encoding.UTF8.GetBytes(content);
await context.Response.Body.WriteAsync(bodyContent, 0, bodyContent.Length).ConfigureAwait(false);
}
else
{
await context.Response.WriteAsync(string.Empty).ConfigureAwait(false);
}
}
else
{
// Simulation leaky bucket algorithm queuing mechanism
var wait = checkResult.RuleCheckResults.Max(d => d.Wait);
if (wait > 0)
{
await Task.Delay((int)wait);
}
await _next(context);
}
}
