Correlating requests

RequestCorrelation.cs

public class RequestCorrelation : IConfigurationAction
{
	public void Configure(BehaviorGraph graph)
	{
		graph
			.Behaviors
			.Each(chain => chain.Prepend(new Wrapper(typeof(SetCorrelationHeaders))));
	}
}

SetCorrelationHeaders.cs

public class SetCorrelationHeaders : BasicBehavior
{
	public const string Correlation_Id = "X-Correlation-Id";

	private readonly IRequestHeaders _headers;
	private readonly IOutputWriter _writer;

	public SetCorrelationHeaders(IRequestHeaders headers, IOutputWriter writer)
		: base(PartialBehavior.Ignored)
	{
		_headers = headers;
		_writer = writer;
	}

	protected override DoNext performInvoke()
	{
		_headers.Value<string>(Correlation_Id, id => _writer.AppendHeader(Correlation_Id, id));
		return DoNext.Continue;
	}
}

trackingRequests.js

(function () {
    var pendingRequests = [];
    var updateRequests = function () {
        $('#PendingRequests').val(pendingRequests.length);
    };
    
    amplify.subscribe('AjaxStarted', function(request) {
        pendingRequests.push(request);
        updateRequests();
    });
    
    amplify.subscribe('AjaxCompleted', function(request) {
        var id = request.correlationId;
        var tmpRequests = [];
        for(var i = 0; i < pendingRequests.lenght; i++) {
            var r = pendingRequests[i];
            if(r.correlationId != id) {
                tmpRequests.push(r);
            }
        }

        pendingRequests.length = 0;
        pendingRequests = tmpRequests;
        updateRequests();
    });
}());