public override async Task OnAuthorizationAsync(HttpActionContext actionContext, CancellationToken cancellationToken)
{
var context = actionContext;
var request = new RateLimitingRequest(
GetRouteTemplate(context),
context.Request.RequestUri.AbsolutePath,
context.Request.Method.Method,
(header) => context.Request.Headers.GetValues(header).ToArray(),
context.RequestContext.Principal as ClaimsPrincipal,
await context.Request.Content.ReadAsStreamAsync().ConfigureAwait(false));
await _rateLimiter.LimitRequestAsync(
request,
() => RateLimitingFilter.GetCustomAttributes(context),
context.Request.Headers.Host,
onPostLimitFuncAsync : async(rateLimitingRequest, policy, rateLimitingResult) =>
{
context.Request.Properties.Add($"RateLimitingResult_{_filterId}", rateLimitingResult);
var clientDecision = OnPostLimit != null ? await OnPostLimit.Invoke(rateLimitingRequest, policy, rateLimitingResult, actionContext).ConfigureAwait(false) : Decision.OK;
var reverted = await RevertIfRequired(rateLimitingResult, context, request, policy, clientDecision).ConfigureAwait(false);
if (reverted)
{
await base.OnAuthorizationAsync(context, cancellationToken).ConfigureAwait(false);
return;
}
if (rateLimitingResult.State == ResultState.Success)
{
if (PostOperationDecisionFuncAsync != null)
{
context.Request.Properties.Add($"PostActionFilterFuncAsync_{_filterId}",
new Func <HttpActionExecutedContext, Task>(async(httpActionExecutedContext) =>
{
var decision =
await PostOperationDecisionFuncAsync.Invoke(rateLimitingRequest, policy, rateLimitingResult, httpActionExecutedContext).ConfigureAwait(false);
await RevertIfRequired(rateLimitingResult, context, request, policy, decision).ConfigureAwait(false);
}));
}
await base.OnAuthorizationAsync(context, cancellationToken).ConfigureAwait(false);
}
else if ((rateLimitingResult.State == ResultState.Throttled || rateLimitingResult.State == ResultState.ThrottledButCompensationFailed) &&
!SimulationMode)
{
await TooManyRequests(context, rateLimitingResult, policy.Name).ConfigureAwait(false);
}
},
getPolicyFuncAsync : GetPolicyFuncAsync != null?new Func <RateLimitingRequest, Task <RateLimitPolicy> >(async(rlr) =>
{
return(await GetPolicyFuncAsync.Invoke(rlr, actionContext).ConfigureAwait(false));
}) : null
).ConfigureAwait(false);
}
private async Task <bool> RevertIfRequired(RateLimitingResult rateLimitingResult, HttpActionContext context,
RateLimitingRequest request, RateLimitPolicy policy, Decision decision)
{
if (decision == Decision.REVERTSUCCESSCOST && rateLimitingResult.State == ResultState.Success)
{
await _rateLimiter.LimitRequestAsync(request,
() => RateLimitingFilter.GetCustomAttributes(context),
context.Request.Headers.Host,
getPolicyFuncAsync : _ => Task.FromResult(policy),
onPostLimitFuncAsync : async(rateLimitingRequest, postPolicy, rateLimitingRevertResult) =>
{
if (rateLimitingRevertResult.State == ResultState.Success)
{
context.Request.Properties[$"RateLimitingResult_{_filterId}"] = rateLimitingRevertResult;
}
if (OnPostLimitRevert != null)
{
await OnPostLimitRevert.Invoke(request, postPolicy, rateLimitingRevertResult, context).ConfigureAwait(false);
}
},
revert : true).ConfigureAwait(false);
return(await Task.FromResult(true));
}
return(await Task.FromResult(false));
}