Setting a timeout for ServerXMLHTTP request - asp-classic

Does anyone know how to set up set up a default action for when a ServerXMLHTTP request times out? I'm using setTimeouts() to set the time out options according to the MSDN site.
Ideally I would like to initialize the request again from the beginning or refresh the page should it time out.
I'm using classic asp and jscript.
Here's my request:
function serverXmlHttp(url) {
var serverXmlHttp;
serverXmlHttp = Server.CreateObject("Msxml2.ServerXMLHTTP.6.0");
// set time out options
serverXmlHttp.setTimeouts(15000,15000,15000,15000);
// does not work
// serverXmlHttp.ontimeout(Response.Write("page has timed out"));
serverXmlHttp.open("GET", url, false);
serverXmlHttp.send();
if (serverXmlHttp.readyState == 4) {
return serverXmlHttp.responseText;
}
}

The important thing is to find out why it is timing out ..
Is the remote Url on the same application as the calling page ?
if so have a look at INFO: Do Not Send ServerXMLHTTP or WinHTTP Requests to the Same Server as you will be facing thread starvation ..

Figured it out. I just need to use a try/catch statement.
function serverXmlHttp(url) {
try {
var serverXmlHttp;
serverXmlHttp = Server.CreateObject("Msxml2.ServerXMLHTTP.6.0");
// set time out options
serverXmlHttp.setTimeouts(15000,15000,15000,15000);
serverXmlHttp.open("GET", url, false);
serverXmlHttp.send();
if (serverXmlHttp.readyState == 4) {
return serverXmlHttp.responseText;
}
catch(error) {
// whatever I want to happen if there's an error
Response.Write("Sorry, your request has timed out");
}
}

Related

Cloudflare Workers - changes are not visible on live (but are in preview)

Hello and thank you for your help.
Sadly support over at CF does not think they need to help me.
I am learning to use workers, and have written a simple HTML injector just to see it working on my site.
this is the full worker code i have:
async function handleRequest(req) {
const res = await fetch(req)
const contentType = res.headers.get("Content-Type")
console.log('contentType: ', contentType)
// If the response is HTML, it can be transformed with
// HTMLRewriter -- otherwise, it should pass through
if (contentType.startsWith("text/html")) {
return rewriter.transform(res)
} else {
return res
}
}
class UserElementHandler {
async element(element) {
element.before("<div class='contbox'><img src='https://coverme.co.il/wp-content/uploads/2020/01/covermeLOGO-01-1024x183.png' style='width:200px;margin:20px;'><h1>testing inserting</h1></div>", {html: true});
// fill in user info using response
}
}
const rewriter = new HTMLRewriter()
.on("h1", new UserElementHandler())
addEventListener("fetch", event => {
event.respondWith(handleRequest(event.request))
})
it just uses element.before to inject some HTML.
in the worker preview pane i can see it!
but on the live site = nothing.
this is the active URL: [https://coverme.co.il/product/%D7%A0%D7%A8-%D7%91%D7%99%D7%A0%D7%95%D7%A0%D7%99-tuberosejasmine/]
these are the 4 routes i have set up to try to catch this, with and without encoding the letters:
coverme.co.il/product/נר-בינוני-tuberosejasmine/
*.coverme.co.il/product/נר-בינוני-tuberosejasmine/*
https://coverme.co.il/product/%D7%A0%D7%A8-%D7%91%D7%99%D7%A0%D7%95%D7%A0%D7%99-tuberosejasmine/
*.coverme.co.il/product/%D7%A0%D7%A8-%D7%91%D7%99%D7%A0%D7%95%D7%A0%D7%99-tuberosejasmine/*
thanks in advance!
I believe the problem here is that you've configured your routes to match "נר-בינוני" unescaped, but the browser will actually percent-encode the URL before sending to the server, therefore the route matching actually operates on percent-escaped URLs. So the actual URL is https://coverme.co.il/product/%D7%A0%D7%A8-%D7%91%D7%99%D7%A0%D7%95%D7%A0%D7%99-tuberosejasmine/, and this does not match your route because %D7%A0%D7%A8-%D7%91%D7%99%D7%A0%D7%95%D7%A0%D7%99 is not considered to be the same as נר-בינוני.
EDIT: Unfortunately, using percent-encoding in your route pattern won't fix the problem, due to a known bug. Unfortunately, it's just not possible to match non-ASCII characters in a Workers route today. We intend to fix this, but it's hard because some sites are accidentally dependent on the broken behavior, so the fix would break them.
What you can potentially do instead is match against coverme.co.il/product/*, and then, inside your worker, check if the path also has נר-בינוני-tuberosejasmine. If it does not, then your fetch event handler should simply return without calling event.respondWith(). This will trigger "default handling" of the request, meaning it will pass through and be sent to your origin server like normal. (Note that you will still be billed for a Workers request, though.)
So, something like this:
addEventListener("fetch", event => {
if (event.request.url.includes(
"coverme.co.il/product/נר-בינוני-tuberosejasmine/")) {
event.respondWith(handle(event.request));
} else {
return; // not a match, use default pass-through handling
}
})

ASP.Net Core HTTP Request Connections getting stuck

We have a simple application in ASP.NET Core which calls a website and returns the content. The Controller method looks like this:
[HttpGet("test/get")]
public ActionResult<string> TestGet()
{
var client = new WebClient
{
BaseAddress = "http://v-dev-a"
};
return client.DownloadString("/");
}
The URL which we call is just the default page of an IIS. I am using Apache JMeter to test 1000 requests in 10 seconds. I have always the same issue, after about 300-400 requests it gets stuck for a few minutes and nothing works. The appplication which holds the controller is completely frozen.
In the performance monitor (MMC) I see that the connection are at 100%.
I tried the same code with ASP.NET 4.7.2 and it runs without any issues.
I also read about that the dispose of the WebClient does not work and I should make it static. See here
Also the deactivation of the KeepAlive did not help:
public class QPWebClient : WebClient
{
protected override WebRequest GetWebRequest(Uri address)
{
var request = base.GetWebRequest(address);
if (request is HttpWebRequest)
{
((HttpWebRequest)request).KeepAlive = false;
}
return request;
}
}
The HttpClient hast the same issue, it does not change anything
With dependency injection like recommended here there is an exception throw that the web client can't handle more request at the same time.
Another unsuccessful try was to change ConnectionLimit and SetTcpKeepAlive in ServicePoint
So I am out of ideas how to solve this issue. Last idea is to move the application to ASP.NET. Does anyone of you have an idea or faced already the same issue?

Check logged user with normal and ajax request

I use interceptor to check if a user is logged in every controller call like this :
public boolean preHandle(HttpServletRequest request,HttpServletResponse response, Object handler) {
if(request.getSession().getAttribute("user") == null) {
response.sendRedirect("redirect:/login?next="+
URLEncoder.encode(
request.getRequestURL().toString() + "" +
(request.getQueryString() != null ? "?" + request.getQueryString() : "")
,"utf-8");
return false;
}
return true;
}
It work fine for normal request but for ajax request i can't make a response.sendRedirect(..).
How to know if it's a ajax or normal request ?
How can i do it like if i got a ajax error ?
$.ajax({
.....
success : function(data) { ...... },
error : function(){
alert("login error"); // or
document.location = '/path/login' // or something else
}
});
There a other way to handle it rather than using interceptor ?
1. How to know if it's a ajax or normal request ?
You can check inside your interceptor for the existence of the X-Requested-With header. This header is always added to the ajax request by the jQuery library (to my knowing almost all major js libraries add it as well) with the purpose of preventing the Cross-Site request forgery. To figure out if the request is ajax, you can write your preHandle method like
public boolean preHandle(HttpServletRequest request,HttpServletResponse response, Object handler) {
String requestedWith = request.getHeader("X-Requested-With");
Boolean isAjax = requestedWith != null ? "XMLHttpRequest".equals(requestedWith) : false;
...
}
2. How can i do it like if i got a ajax error ?
As you've already noticed, ajax request don't recognize server side redirects, as the intention of the server side redirects is to be transparent to the client. In the case of an ajax request, don't do redirect rather set some status code to the response e.g. response.setStatus(respCode) or add a custom header e.g. response.setHeader("Location", "/path/login"), and read it through in the jQuery's complete method which is a callback that follows after either success or error, e.g.
$.ajax({
//...
complete: function(xhr, textStatus) {
console.log(xhr.status);
console.log(xhr.getResponseHeader('Location'));
// do something e.g. redirect
}
});
3. There a other way to handle it rather than using interceptor ?
Definitely. Checkout Spring Security. Its a framework, and adds a bit to the learning curve, but its well worth it. It will add much more than a custom solution, e.g. you'll get authorization mechanism on top of the authentication. When your application matures, you'll notice that the straigthforward implementation that you're on to now, has quite a few security flaws that are not hard to exploit e.g. session fixation, where spring security can easily protect you. There's plenty of examples online, and you'll get better support here on the SO in comparison to any custom solution. You can unit test it, an asset I personally value very much
You could simply:
Refuse ajax requests before the user is properly logged in
once the user logs in, set a security token in the session or somewhere
pass that token in the ajax request and use that token to validate on the server side prehandle
in your case you would check the existence of the token before running into the code
Also, the preHandle does not have to apply to every routes, you could also have different routes each with different authorisation, prehandle, code.

Keep application users logged in for 20 Hours

We have a asp.net + MSSQL Server DB web based application with approx 100 users. Its hosted on our intranet on IIS7.0. We are using Forms Authentication
We need to keep the users (anyone who is logged in ) to be logged in for 20 Hours exactly. Means no one should be kicked out ( session time out ) of the application before 20 Hours even if he is idle.
We tried many of the suggested approaches like web config changes etc but nothing is working.
Our main question is : Will we have to do some code changes to keep the user sessions alive for this ( or any duration). Can someone suggest or point us to a solution?
Whenever you make a request to the server the session timeout resets. So you can just make an ajax call to an empty HTTP handler on the server, but make sure the handler's cache is disabled, otherwise the browser will cache your handler and won't make a new request.
KeepSessionAlive.ashx.cs
public class KeepSessionAlive : IHttpHandler, IRequiresSessionState
{
public void ProcessRequest(HttpContext context)
{
context.Response.Cache.SetCacheability(HttpCacheability.NoCache);
context.Response.Cache.SetExpires(DateTime.UtcNow.AddMinutes(-1));
context.Response.Cache.SetNoStore();
context.Response.Cache.SetNoServerCaching();
}
}
.JS:
window.onload = function () {
setInterval("KeepSessionAlive()", 60000)
}
function KeepSessionAlive() {
url = "/KeepSessionAlive.ashx?";
var xmlHttp = new XMLHttpRequest();
xmlHttp.open("GET", url, true);
xmlHttp.send();
}

How to detect user cancels request

I'm trying out Node.js by writing a very basic http/web caching proxy, and have hit something I haven't managed to break through.
Assuming I have a very basic proxy functionality (listen to request, pipe it to external server, wait for response, pipe it back to client), how do I detect when the client (web browser) cancels the request? When the user clicks "Stop"/Esc on his browser, the browser doesn't send me any "request" or info and attaching a callback for when the "response" connection ends doesn't get called.
Here's what I mean:
http.createServer (clientRequest, clientResponse) {
var client = http.createClient (port, hostname);
var request = client.request (method, url, headers);
request.addListener ('response', function(response){
response.addListener ('data', function(chunk){
// forward data to clientResponse..
}
response.addListener ('end', function(){
// end clientResponse..
}
});
clientResponse.addListener('end', function(){
// this never gets called :(
// I want it to terminate the request/response created just above
}
}
Turns out I should be binding to the "close" event instead of the "end" event of the request.
That does actually make sense.
I'm posting this here for anyone else who might encounter the same issue:
clientResponse.addListener('close', function(){
// this gets called when the user terminates his request
}

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