Create HTTP POST method in ASP.NET which accepts CGI variables - asp.net

I have an ASP.NET (.NET v4) web application running on IIS 7.5. I have a 3rd party which wants to pass information to my system. They support passing this information using HTTP POST, the information they provide is:
"This method simply calls a script on your server and passes each
field as a CGI variable. When you have received the data your server
should return a '1' on a line by itself to indicate success. Anything
else will generate an error on our server which will be investigated.
To set up this delivery method we need a URL to post to. We can use
HTTP or HTTPS."
My web application currently implements many WCF services but as I don't know what the variables passed in will be I cannot define a specific contract. Can I create a normal aspx page which they can post to and then read each of the parameters passed and do the appropriate processing.
If I do this how do I send back a line containing '1'?
Do I need to do anything else to make this HTTP POST compatible.

The last time I had to tackle a similar situation, i did it using a standard ASPX page, and it all worked quite well.
In my case the output was XML, so I had to make sure that I changed the output mime type to match "text/xml" in my case.. "text/plain" I would guess in yours..
Anyway, C# sharp code below, and make sure that your ASPX file has ONLY the very top line in, that is:
<%# Page Language="C#" AutoEventWireup="true" CodeBehind="register.aspx.cs" Inherits="myservices.register" ContentType="text/xml" %>
and nothing else, no carriage returns or anything.
Then do all your work in the code behind:
protected void Page_Load(object sender, EventArgs e)
{
Response.Clear();
Response.ContentType = "text/plain";
//Get your CGI variables here... you will have to get them to tell you what to expect
string myparam = (string)Request.QueryString["myparam"];
//do what ever you need here with your variables
Response.Write("1");
Response.End();
}// End page load handler
If you need to follow the one with a carriage return, then i believe you can use the carriage return property in the system.environment object, but I've not got doc's to hand to look it up. That should however get you started.
The MOST important thing to remember is to make sure NOTHING is output from the aspx, not even a carriage return.
I've previously written an article on my Blog about how to use this method for producing phone directories for Cisco-IP phones if you want to read it. You can find it here: http://shawtyds.wordpress.com/2009/09/26/cisco-ip-phone-directories-using-c/

Related

Call VB Sub from Embedded GeckoWebBrowser using window.external.Sub1();

I have an aspx page on my webserver which I load through an embedded web browser on a windows form. I am able to call the Sub1 from javascript window.external procedure. This is only when using the standard VB control WebBrowser. I have the necessary permissions active with
<PermissionSet(SecurityAction.Demand, Name:="FullTrust")> _
<System.Runtime.InteropServices.ComVisibleAttribute(True)> _
This works just fine. However, I am in need of using GeckoFx as my javascript is too complex for the standard WebBrowser as well as my styling.
I have tried the same approach as is, just with the geckobrowser, but it does not work at all, is there any:
GeckoPrefereces.User("somesetting") = True
that I need to activate to get it to work or is there something else I am missing?
I would just like to call the 'form close' procedure of my windows form, from the webpage which is embedded in the GeckoBrowserControl.
Refer the following link for your answer as it is solved here.
How to call C# method in javascript by using GeckoFX as the wrapper of XULRunner
Change this process to C# as VB cannot send the message to a procedure, only store the value and this creates a difficult situation in reading the data later.
then:
private void showMessage(string s)
{
if (s == "some data")
{
//Do stuff here you need to, ie. close the form, etc
}
}
This allows you to read the message sent and do with it what you wish.
Also important:
browser.AddMessageEventListener("myFunction", ((string s) => this.showMessage(s)));
must be before you load the html or the url
myBrowser.Navigate("www.google.com");

Sharepoint If-Modified-Since

I wrote a handler to be used within SharePoint that will generate a JSON string from a given parameter in the query-string. This JSON string will then be used by a JS function to display the relevant data in HTML to the client, however, the call is somewhat costly and would like to cache the output once.
The handler currently caters for everything regarding OUTPUT cache and tested within an application bares fruits, however, I'm baffled by the fact that, specifically in SharePoint (2007) the "If-Modified-Since" header attribute never appears, basically it always comes back as null.
I found blog-on-blog that discuss this in length in regards to images, and include files but I can't find anything specific regarding this with pages (ASPX, AXD, ASHX) and the handler self.
My only assumption here is the fact that I'm using an AXD file, which is not directly supported by OUTPUT cache by default?
The code looks something like:
bool isModifiedSinceLast = (context.Request.Headers.Get("If-Modified-Since") != null)
: true
? false;
if (!isModifiedSinceLast)
{
context.Response.Headers.AppendHeader("If-Modified-Since", Guid.NewGuid());
}
else
{
// complete the call from cache
}
Thanks,
Eric

jQuery ajax call containing script-tag in data

I read some values from text boxes and send them via jQuerys post method to an server. If the user enters text containing something like "bla bla", the call fails. The data looks like this in that case:
var data = { myKey: 'bla <script> bla' };
And I send it to the server like this:
$.post(targetUrl, data, function(x) {...});
On the server side (an Asp.Net web form) it looks like the call never reaches the server. Any hint how to solve that? If there's a convenient function which cleans data from bad tags, that would be fine too.
Have you desactivate the validate request of your aspx page?
add this in your page declaration: validateRequest="false"
To strip tags using a jQuery function:
jQuery.fn.stripTags = function() {
return this.replaceWith( this.html().replace(/<\/?[^>]+>/gi, '') );
};
Do you receive a page_load in ASP.NET? If yes, isn't there anything in Request.Params?
I would suggest escaping your values client side using the javascript escape function as shown below
var data = { myKey: escape('bla <script> bla') };
Once you have done that, you can retrieve the correct value on the server side using the following (.Net Code)
HttpUtility.UrlDecode(param_value_to_decode)
I tested this and the correct value is being passed correctly to the server via the post request.
Hope this helps.
Additional Info : I forgot to mention the cause of the error. When inspecting the request using firebug, it returns a "500 Internal Server Error - A potentially dangerous Request.Form value was detected from...". This is a built in protection mechanism from asp.net to protect against script injection. The following page directive ValidateRequest="false" did not solve the problem as expected (Works in traditional WebForms). It might be something specific to the Mvc platform, not to sure. The above solution does work, so just use that.
Regards
G

URL Encoding being lost before processing - ASP.net

I am building a web-store that uses URL encoding extensively.
I have a list of Departments & Categories in my database which I use to generate the links. These are, of course, URL encoded before they are sent.
Some Typical Links are...
/MySite/Store/Countertop+Equipment/Can+Openers.aspx
/MySite/Store/Dinnerware.aspx
/MySite/Store/Kitchen/Pastry%2f+Decorating.aspx
In my HTTPHandler I call app.Request.Path to obtain the current path. The string returned by this call is no longer URL encoded which is making it impossible for me to parse correctly.
Once the URL encoding is lost
/MySite/Store/Kitchen/Pastry%2f+Decorating.aspx becomes
/MySite/Store/Kitchen/Pastry/Decorating.aspx.
This is obviously breaking the method that converts the URL to a QueryString.
Anyone know how to fix this?
Here is the core of my HTTPHandler
public void Init(System.Web.HttpApplication app)
{
app.BeginRequest += new EventHandler(Application_BeginRequest);
}
private void Application_BeginRequest(object sender, EventArgs e)
{
System.Web.HttpApplication app = (System.Web.HttpApplication)sender;
string realUrl = GetRealUrl(app.Request.Path);
if (!String.IsNullOrEmpty(realUrl))
app.Context.RewritePath(realUrl, false);
}
I really appreciate your help!
You cannot use Request.Url (including Url..PathAndQuery, AbsolutePath etc) as its OriginalString is already decoded.
So there is no point to use Request.Url at all and you can try to play with following:
Request.AppRelativeCurrentExecutionFilePath
Request.CurrentExecutionFilePath
Or in a worst-case scenario you'll need to parse the Url:
[Test]
public void RewriteProoveOfConcept() {
var path = #"/MySite/Store/Kitchen/Pastry%2f+Decorating.aspx";
var res = Regex.Replace(path, #"/(.+)/(.+)/(.+)/(.+)\.aspx", #"/$1/YourPage.aspx?category1=$2&category2=$3&category3=$4");
Assert.AreEqual(#"/MySite/YourPage.aspx?category1=Store&category2=Kitchen&category3=Pastry%2f+Decorating", res);
}
This shows how you can get the URL:
/MySite/YourPage.aspx?category1=Store&category2=Kitchen&category3=Pastry%2f+Decorating
from:
/MySite/Store/Kitchen/Pastry%2f+Decorating.aspx
Additionally consider using Routing instead of UrlRewrite.
Cheers,
Dmitriy.
Try the AbsolutePath or PathAndQuery properties on the Request object. Both of them should maintain the url encoding.
You can UrlEncode the URL before parsing it. Or better yet, keep URL's non-encoded in database. You don't even need to encode them if you use HyperLink control.
It turns out that the issue is occurring in IIS before .Net even gets its hands on the request. It appears that this is a dead end.
An additional word of warning is that my IIS test server (XP) was rejecting requests containing encoded amperstands as a security risk and could not be persuaded to cooperate with anything short of a registry edit. Not sure if this goes for all versions, but even if a server variable can be retrieved this seems like another good reason to use a different tactic.
Here is the follow-up question with the accepted solution-
ASP.Net URL Encoding

Process raw HTTP request content

I am doing an e-commerce solution in ASP.NET which uses PayPal's Website Payments Standard service. Together with that I use a service they offer (Payment Data Transfer) that sends you back order information after a user has completed a payment. The final thing I need to do is to parse the POST request from them and persist the info in it. The HTTP request's content is in this form :
SUCCESS
first_name=Jane+Doe
last_name=Smith
payment_status=Completed
payer_email=janedoesmith%40hotmail.com
payment_gross=3.99
mc_currency=USD
custom=For+the+purchase+of+the+rare+book+Green+Eggs+%26+Ham
Basically I want to parse this information and do something meaningful, like send it through e-mail or save it in DB. My question is what is the right approach to do parsing raw HTTP data in ASP.NET, not how the parsing itself is done.
Something like this placed in your onload event.
if (Request.RequestType == "POST")
{
using (StreamReader sr = new StreamReader(Request.InputStream))
{
if (sr.ReadLine() == "SUCCESS")
{
/* Do your parsing here */
}
}
}
Mind you that they might want some special sort of response to (ie; not your full webpage), so you might do something like this after you're done parsing.
Response.Clear();
Response.ContentType = "text/plain";
Response.Write("Thanks!");
Response.End();
Update: this should be done in a Generic Handler (.ashx) file in order to avoid a great deal of overhead from the page model. Check out this article for more information about .ashx files
Use an IHttpHandler and avoid the Page model overhead (which you don't need), but use Request.Form to get the values so you don't have to parse name value pairs yourself. Just pretend you're in PHP or Classic ASP (or ASP.NET MVC, for that matter). ;)
I'd strongly recommend saving each request to some file.
This way, you can always go back to the actual contents of it later. You can thank me later, when you find that hostile-endian, koi-8 encoded, [...], whatever it was that stumped your parser...
Well if the incoming data is in a standard form encoded POST format, then using the Request.Form array will give you all the data in a nice to handle manner.
If not then I can't see any way other than using Request.InputStream.
If I'm reading your question right, I think you're looking for the InputStream property on the Request object. Keep in mind that this is a firehose stream, so you can't reset it.

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