/// <summary>Dispatch an HTTP request.</summary>
/// <param name="request">The response message to validate.</param>
/// <param name="dispatcher">A method which executes the request.</param>
/// <returns>The final HTTP response.</returns>
public async Task <HttpResponseMessage> ExecuteAsync(IRequest request, Func <IRequest, Task <HttpResponseMessage> > dispatcher)
{
int attempt = 0;
while (true)
{
// dispatch request
attempt++;
var response = await DispatchRequest(request, dispatcher).ConfigureAwait(false);
// check if the token needs to be refreshed
if (response.StatusCode == HttpStatusCode.Unauthorized)
{
var responseContent = await response.Content.ReadAsStringAsync(null).ConfigureAwait(false);
var jObject = JObject.Parse(responseContent);
var message = jObject.GetPropertyValue("message", string.Empty);
if (message.StartsWith("access token is expired", StringComparison.OrdinalIgnoreCase))
{
var refreshedToken = _tokenHandler.RefreshTokenIfNecessary(true);
request = request.WithBearerAuthentication(refreshedToken);
response = await DispatchRequest(request, dispatcher);
}
}
// find the applicable retry configuration, if any
IRetryConfig retryConfig = RetryConfig.None();
bool shouldRetry = false;
foreach (var config in _retryConfigs)
{
if (config.ShouldRetry(response))
{
retryConfig = config;
shouldRetry = true;
break;
}
}
// exit if there is no need to retry the request
if (!shouldRetry)
{
return(response);
}
int maxAttempt = 1 + retryConfig?.MaxRetries ?? 0;
// throw an exception if we have reached the maximum number of retries
if (attempt > maxAttempt)
{
throw new ApiException(new Response(response, request.Formatters), $"The HTTP request failed, and the retry coordinator gave up after the maximum {maxAttempt} retries");
}
// set up retry
TimeSpan delay = retryConfig.GetDelay(attempt, response);
if (delay.TotalMilliseconds > 0)
{
await Task.Delay(delay).ConfigureAwait(false);
}
}
}