Web Development

1-Dec-06 15:21

I'm trying to write a simple javascript script that will enable the web page to send commands to my proxy server that I'm developing.

However it appears that both Firefox and IE block any attempt to use the XMLHttpRequest object to send web requests.

Is there ANY way I can get javascript to send ANY kind of information over the wire that my proxy server can intercept and provide custom services?

--------------------------------

"All that is necessary for the forces of evil to win in the world is for enough good men to do nothing" -- Edmund Burke

Bradml1-Dec-06 15:34

1-Dec-06 15:34

I don't completely understand, are you saying that IE and Firefox aren't letting you make Ajax calls?

The XMLHttpRequest does send web requests.

In addition what sort of proxy are you using?

Brad
Australian
By contacting your lawyer you negate the right to sue me.

Richard Andrew x641-Dec-06 15:54

1-Dec-06 15:54

Hi Brad,

I wrote a simple script that calls open( "GET", url, true ); and the Error Console in Firefox says, "Permission denied to call method XMHttpRequest.open"

The proxy is something I'm developing. It's going to be an intercepting proxy.

In the code below, the alert( "Request sent" )never gets called:

var xmlhttp;

function loadPage( url )
{
  xmlhttp=new XMLHttpRequest();
  xmlhttp.onreadystatechange=state_Change;
  xmlhttp.open("GET",url,true);
  xmlhttp.send(null);
  alert( "Request Sent" );
}

function state_Change()
{
// if xmlhttp shows "loaded"
alert("State Change" );
if (xmlhttp.readyState==4)
  {
  // if "OK"
  if (xmlhttp.status==200)
    {
    // ...some code here...
	alert( "200 OK!" );
    }
  else
    {
    alert("Problem retrieving XML data");
    }
  }
}

--------------------------------

"All that is necessary for the forces of evil to win in the world is for enough good men to do nothing" -- Edmund Burke

Bradml1-Dec-06 16:14

1-Dec-06 16:14

Can you post all the javascript that relates to the request here?

Brad
Australian
By contacting your lawyer you negate the right to sue me.

Richard Andrew x641-Dec-06 16:22

1-Dec-06 16:22

I'm just beginning to learn javascript, so the code I'm trying to use is very simple: ( Thanks for your help ) It says "window.removed" below, but that's something CodeProject did. The real code says "onload"

<script language = "javascript" > 
<!--
function myonload(  )
{
	loadDoc( "http://www.google.com" );

}

window.onload = myonload;
var xmlhttp;


function state_Change()
{
// if xmlhttp shows "loaded"
alert("State Change" );
if (xmlhttp.readyState==4)
  {
  // if "OK"
  if (xmlhttp.status==200)
    {
    // ...some code here...
	alert( "200 OK!" );
    }
  else
    {
    alert("Problem retrieving XML data");
    }
  }
}

function loadDoc( url )
{
  xmlhttp=new XMLHttpRequest();
  xmlhttp.removed=state_Change;
  xmlhttp.open("GET",url,true);
  xmlhttp.send(null);
  alert( "Request Sent" );
}

//-->
</script>

--------------------------------

"All that is necessary for the forces of evil to win in the world is for enough good men to do nothing" -- Edmund Burke

Bradml1-Dec-06 16:32

1-Dec-06 16:32

My suggestion is to revise the Mozilla tutorial on Ajax.

http://developer.mozilla.org/en/docs/AJAX:Getting_Started[^]

I am sorry I could not have been of more help, but I can't really see an error with the script.

Brad
Australian
By contacting your lawyer you negate the right to sue me.

Richard Andrew x641-Dec-06 16:34

1-Dec-06 16:34

That's OK, thanks for your participation anyway.

I will take a look at that link and see if it can provide some clues. Smile | :)

--------------------------------

"All that is necessary for the forces of evil to win in the world is for enough good men to do nothing" -- Edmund Burke

Richard Andrew x641-Dec-06 16:38

1-Dec-06 16:38

Brad, your link DID provide the answer. It turns out that you're not allowed to make requests to domains other than the one that the page belongs to.

So because I was requesting Google, it gave the permission denied error.

Thanks!

--------------------------------

"All that is necessary for the forces of evil to win in the world is for enough good men to do nothing" -- Edmund Burke

Bradml1-Dec-06 16:54

1-Dec-06 16:54

That must be new to FF. No problem btw.

Thanks for asking the question, I could have seen myself making the same mistake.

BTW a quick hack to get past this is to build PHP/ASP application that will call the requested page, and have that uploaded to ur server.

Brad
Australian
By contacting your lawyer you negate the right to sue me.

RichardGrimmer2-Dec-06 7:08

RichardGrimmer

2-Dec-06 7:08

Richie308 wrote:
It turns out that you're not allowed to make requests to domains other than the one that the page belongs to.

Much as it pains me to admit it, apparently ATLAS provides a way around this.

"Now I guess I'll sit back and watch people misinterpret what I just said......"
Christian Graus At The Soapbox

Caching and State Management within WebServices

Shog⁹4-Dec-06 11:16

Shog⁹

4-Dec-06 11:16

Richie308 wrote:
It turns out that you're not allowed to make requests to domains other than the one that the page belongs to.

It would be a huge security hole otherwise. There are ways of getting around this for most browsers, but they require the user to explicitly allow the exception - so, they're more useful for intranet-type development.

RadioButton1-Dec-06 11:01

RadioButton

1-Dec-06 11:01

Hello,

I was wondering 'if this is even possible' what is the "right" way to perform caching and state management within WebServices with ASP.Net 2.0? Or should you just use System.IO.MemoryStream? D'Oh! | :doh:

My Scenario is:

UI will hit WebService lets say every 10 min and request data. However I don't want every user hitting the WebService to make a call to SQL.

Just need to be pointed in the right direction.

Thank you for the help.
RB

Re: Caching and State Management within WebServices

Dominic Pettifer1-Dec-06 14:07

Dominic Pettifer

1-Dec-06 14:07

While State Management IS supported, it's generally not a recommended practice to implement it with web services due to scalability and practical reasons. Also you need to make sure that whatever is calling it also supports state management, typically via HTTP Cookies.

You implement it like this...

[WebMethod(EnableSession=true)]<br />
public Object DoSomething(){}

Then, providing you're deriving from System.Web.Services.WebService, you use Session same way you use it in ASP.NET web pages. However, if the caller doesn't support stateful webservice, then the Session values will be emptied with every call. If the caller is also a .NET app then enabling stateful Web Service support is entirely possible, write back and I'll post some code.

As for Caching, yes this is possible and recommended. You could do this manually using the Cache property of System.Web.Services.WebService (same way as ASP.NET web pages), or get the WebService to handle Caching itself like this...

[WebMethod(CacheDuration=600)]<br />
public Object DoSomething(){}

This will cache the output of the web service for 10 minutes (600 seconds). It's also intelligent enough to detect input parameters in the WebMethod and Cache different outputs depending on the input params. Although if lots a input params are used, you could end up caching lots of data and flooding the servers memory, so be careful.

Dominic Pettifer

Blog: www.dominicpettifer.co.uk

Re: Caching and State Management within WebServices

RadioButton4-Dec-06 3:51

RadioButton

4-Dec-06 3:51

Thank you very much for the information. Very helpful. Big Grin | :-D

SMS Website

Ashish Porwal30-Nov-06 20:15

Ashish Porwal

30-Nov-06 20:15

I am student of final year engineering student. I selected “SMS Website” as my project topic. In this I have to send Bulk SMS through website and provide other kind of services related to SMS.
Please tell me which steps I should follow.
Please send me some material or any kind of source code related to it.

I need your help.
Thank you!!!

Contact Me: ashish.0619@gmail.com

Re: SMS Website

Bradml30-Nov-06 20:40