POST data to a Flex/Flash (mxml) application - c#

I have Flex application requiring to filter users depending on there database groups. Depending on which group they are, the're is a config.xml file that is use to populate the swf.
Here is how I figure how to do this :
1. The client comes to a .aspx page with a form requiring a username and a password.
2. On the server side I confirm the user credential
3. Once the username/password is valid I redirect to the mxml file with the config.xml file in the html headers (post).
My problem comes when I need to get the post data from the http request. Let's say I have this code :
<mx:Application initialize="init()">
<mx:Script>
<![CDATA[
private function init():void
{
// get the post data here
}
/* More code here */
]]>
</mx:Script>
</mx:Application>
How do I get the post data on the init() function.
Thank you.

For those that would be interested, I've found some ressources on the Adobe Flex 3 Ressource center.
Basically there is no current way to pass data with the POST method. You can either add the parameters at the end of you swf url (GET method) as shown here : http://livedocs.adobe.com/flex/3/html/help.html?content=deep_linking_5.html#245869
The other way is to embed them in the page with the flashVars method shown here : http://livedocs.adobe.com/flex/3/html/help.html?content=passingarguments_3.html#229997
If you still wonder, how I'll manage to do this if you run to in the same situation. Here is my idea (feel free to share if you have different vision) :
1.User logs in login.aspx
2.Depending on the credentials of the users the server side code modify the index.html file to embed the correct xml file in the flash object.
3.With the FlashVars method, I get back the xml file path and job done!
If you ever run in a similar situation and need help contact me.

I don't think it's possible to get the POST data, but others might have a way. An alternative solution would be:
User logs in: login.aspx
User directed to Flash content: content.html embedding content.swf
Flash requests config.xml from server: content.swf makes HTTP request for config.xml.aspx
Server provides user's configuration in config.xml.aspx
In your init() function, you'd make the URLLoader request to get the configuration, and you'd do the configuration in the Event.COMPLETE handler.
Another possibility is to use HTTP cookies--not handled natively by Flash, but you can get to them via Javascript--see this CookieUtil class.

Related

Use HTML string from Server Requets, and create the web page without saving it a file [in C#]

I´m sending the value of a variable via POST to a PHP page in C#. I get the data stream from the server that has all the web page in HTML with the value of the POST. This information is stored in a string variable.
I would like to open a browser and show the web page (maybe using System.Diagnostics.Process.Start("URL")), without having to save it in a file, this is showing the page in the moment and, when the browser is closed, no file is stored in the server.
Any idea?
Drop a WebBrowser control into a new form webBrowser1 and set its DocumentTextProperty to your result html
webBrowser1.DocumentText = ("<html><body>hello world</body></html>");
source:
<html><body>hello world</body></html>
You aren't going to be able to do that in an agnostic way.
If you simply wanted to open the URL in a browser, then using the Process class would work.
Unfortunately, in your case, you already have the content from creating the POST to the server, and you really want to stream that response in your application to the browser.
It's possible among the some browsers, but it's not able to be done in an agnostic way (and it's complicated even when targeting a specific browser).
To complicate matters, you want the browser to believe that the stream you are sending it is really coming from the server, when in reality, it's not.
I believe that your best bet would be to save the response to the file system in a temp file. However, before you do, add the <base> tag to the file with the URL that the file came from. This way, relative URLs will resolve correctly when rendered in the browser.
Then, just open the temporary file in the browser using the Process class.

PDF binary data output in .NET

I have a question about outputting PDF files. Currently I'm storing the PDF in the database in binary form. I'm outputting the PDF file via a URL such as:
http://myhost.com/FileManager.aspx?FileId=8465b2f9-b64e-4a9a-a449-94b5adb3b278
so from what I could deduce, to the browser this is an .aspx page that is loading and not a PDF. Firefox and IE interpret this correctly and launch Adobe Acrobat, however since Chrome (12.0.742.112) has its own implementation of a PDF reader, it will open the file correctly, but then when someone goes to save the file in chrome, it wants to save it as a .aspx. If I simply rename the .aspx to .pdf, the file downloads correctly. However, I"m trying to avoid telling my customer that s/he may have to take that extra step.
When I chose to look at the headers that loaded in Chrome via Web Inspector, I see this:
FileManager.aspx:-1 Resource interpreted as Document but transferred
with MIME type application/pdf
I can completely understand why Chrome would say this.
Furthermore, I get a save as box upon page load when I add:
Response.AddHeader("content-disposition", "attachment;filename=blah.pdf");
However, I was hoping to just keep the file in a browser. So aside from using some URL Rewrite, is there a way I can manipulate the HTTP Headers to simply open the page as a PDF and save correctly in Chrome?
Lastly, I tried using a WebService, but I can't seem to write the binary data to the page.
this.Context.Response.BinaryWrite(bytes);
Any help is appreciated!
In the web application's top-level web.config, add the following <add> element to the <httpHandlers> section:
<httpHandlers>
<add verb="*" path="FileManager.pdf" type="ProjectName.FileManager" />
...where ProjectName.FileManager is the full name (namespace and classname) of the FileManager class in FileManager.aspx.cs.
This tells ASP.NET to handle the path /FileManager.pdf using the handler defined by ProjectName.FileManager. (System.Web.UI.Page implements the IHttpHandler interface, so every webform is a handler.)
Now you can serve the PDFs via a URL with a .pdf extension like so:
http://myhost.com/FileManager.pdf?FileId=8465b2f9-b64e-4a9a-a449-94b5adb3b278
You do not need to rename the physical FileManager.aspx file. When the user enters /FileManager.pdf?FileId=foo in the browser, ASP.NET will handle the request with the ProjectName.FileManager class defined in FileManager.aspx.
Note:
The above should work on Cassini (the Visual Studio "mini" webserver) with no further changes. However IIS by default only sends *.aspx, *.asmx, *.ashx requests to ASP.NET. Therefore, for the above to work on IIS, you need to tell it to send requests for /FileManager.pdf to ASP.NET. That is, you need to configure a "mapping".
With IIS 6 you need to configure the mapping using IIS manager.
With IIS 7 you can configure a mapping from your web.config--this makes deployment easier, but it depends on how your hosting is set up.
Something that worked for me was to add the intended filename between the application page name (in your case, FileManager.aspx) and the query mark (the ? mark).
So, in the end, you'd have something like this:
http://myhost.com/FileManager.aspx/myfile.pdf?FileId=8465b2f9-b64e-4a9a-a449-94b5adb3b278
Surprisingly, the correct application will run (Filemanager.aspx), the variables will be passed unharmed (FileId), the result will be treated as inline (if you didn't change it to attachment, that is) but the browser will think that the filename to use, in case the user wants to save the page, is myfile.pdf.

How to POST Data to another web application (cross domain)

Please consider the following scenario,
There are two web applications App1 & App2. A user would submit his information on App1 though a form. On click of a specific button/link on App1, the same data should be posted to a page on App2 and the user should also be redirected to the same page on App2.
I would like some help in finding out the best way to implement this functionality.
One of the approaches that I have already tried out is by creating a temporary HTML form at runtime, setting the action attribute of the form to the App2 Page and get the form posted by using javascript submit. The data can then be fetched on App2 page by using the response.form object.
This approach works well, but i was still wondering if there is any other way to implement the required functionality.
I would really appriciate if you can give some insights on using RESTful webservices to implement this, or else, using some HttpModule to intercept requests at App1 and modify redirect response to app2 or any other approach that you might find fit for the purpose.
Edit:
Using querystring isnt an option for me.
I've had a need to do similar things with feed agregation and building rss feeds from web page content on different domains.
User Gets app1 page, fills in details and submits then on the server for app1 I have a method that looks like this ...
HTMLDocument FetchURL( string url )
{
WebClient wc = new WebClient();
string remoteContent = wc.DownloadString(url);
// mshtml api is very weird but lets just say you have to do things this way ...
HtmlDocument doc = new HTMLDocument();
IHTMLDocument2 doc2 = (IHTMLDocument2)doc;
doc2.write(new object[] { remoteContent });
return (HTMLDocument)doc2;
}
This function does 2 things of use ...
It gets the page of content at "url"
It parses that content in to a HTMLDocument object
Once you have this function you can then call it passing it the url to the remote page and get back a html doucment.
The functions in the HTMLDocument object will allow you to do javascript like dom queries such as :
docObject.GetElementById("id");
I then have different functions that do different things with this object based on the page / site i'm returning data from.
There is however one fatal flaw here ...
This is likely to work really well with sites that don't change much in structure and are built by code but not so well on less dynamic sites.
With stackoverflow for example its easy to pull out a question and the accepted answer for that question so I could use this code to pull and publish content from here on my own web site.
However ...
This is not going to help you for user / login related details as this sort of information is not shared to generally everyone.
It's bit like me going and trying this to link facebook profiles to my own website, I would have to go through some form of api that asked the user to authenticate their details before making the request.
simply pulling a web page based on a url only will give the other site no authentication information unless that site accepts the user login details in the quesrystring and you already have them.
You may however be able to chain requests by ripping apart my sample method, requesting the login page parsing the results, filling in the form, then posting back using the same web client instance to login then requesting the url.
The idea being that you would have a form that asks the user to put in their login details for the remote site on your site then you go and find their profile page based on that.
This would be best farmed out to a class rather than just a simple method like i have here.
In my case though i was only after something simple (the bbc top 40 uk charts) which i pulled information from not only the bbc but places like amazon, google, and youtube, then i built a page :)
It's neat but serves no functional purpose other than pulling all your other fave sources of info on to 1 page.
If you are already committed to using javascript, then why not an ajax post, and change the window.location based on the response?
You can use HttpServerUtility.Transfer this will preserve your form contents and transfer the user to the new page.
http://msdn.microsoft.com/en-us/library/system.web.httpserverutility.transfer.aspx
I have built something like what you are describing, and I found that using a <form> tag to POST to app2 is the most reliable way... basically, the way you found that worked well.
If App2 is residing on a different domain, it's usually best to create your own interface for the submission, and have that interface handle the posting from App1 to App2.
(Browser) -> Submits form to App1 ->
(App1) -> validate input
-> stores local info
-> creates an HttpRequest/POST object
-> posts to App2
(App2) -> handles the post
<- returns the response
-> confirms the results of App2
<- returns the results to the browser.
In essense, you want to control and proxy requests from your Applications domain to any outside interfaces as much as possible.
Note: I'm answering my own question
just to have a correct answers marked
against it. All the suggestions
provided by various members here are
correct in their own way, but they
were not apt for my requirements.
Hence, I cant accept any of them as
correct.
The way I have Implemented is by creating a custom control which would have a configurable property containing the URL to post data and another one accepting a dictionary object as the data input to be posted.
This control would internally create a HTML form with action attribute set to the URL specified by the user and have the data feilds created out of the dictionary object. This form would then be posted on the button click event on the page hosting this control.

How to secure AJAX request in ASP.NET?

I am developing an application in which I am displaying products in a grid. In the grid there is a column which have a disable/enable icon and on click of that icon I am firing a request through AJAX to my page manageProduct.aspx for enabling/disabling that particular product.
In my ajax request I am passing productID as parameter, so the final ajax query is as
http://example.com/manageProduct.aspx?id=234
Now, if someone (professional hacker or web developer) can get this URL (which is easy to get from my javascript files), then he can make a script which will run as a loop and will disable all my products.
So, I want to know that is there any mechanism, technique or method using which if someone tries to execute that page directly then, it will return an error (a proper message "You're not authorized or something") else if the page is executed from the desired page, like where I am displaying product list, then it will ecxecute properly.
Basically I wnat to secure my AJAX requests, so taht no one can directly execute them.
In PHP:
In php my colleague secure this PHP pages by checking the refrer of the page. as below:
$back_link = $_SERVER['HTTP_REFERER'];
if ($back_link =='')
{
echo 'You are not authorized to execute this page';
}
else
{
//coding
}
Please tell me how to the same or any other different but secure techique in ASP.NET (C#), I am using jQUERY in my app for making ajax requests.
Thanks
Forget about using the referer - it is trivial to forge. There is no way to reliably tell if a request is being made directly or as a response to something else.
If you want to stop unauthorised people from having an effect on the system by requesting a URL, then you need something smarter then that to determine their authorisation level (probably a password system implemented with HTTP Basic Auth or Cookies).
Whatever you do, don't rely on http headers like 'HTTP_REFERER', as they can be easily spoofed.
You need to check in your service that your user is logged in. Writing a good secure login system isn't easy either but that is what you need to do, or use the built in "forms authentication".
Also, do not use sequential product id's, use uniqueidentifiers, you can still have an integer product id for display but for all other uses like the one you describe you will want to use the product uniqueidentifier/guid.

Static files and authentication in ASP.net

Say I have a virtual folder /topFolder/ in IIS7, and in that folder there can be any file that can be displayed in a browser (xml, html, swf, doc etc - typically "unmanaged" resources from the IIS perspective).
Before giving the request permission to open any file below the folder, I need to check some session variables in order to see if the user has a "license" for the subfolder and file in question.
I've tried implementing a module with IHttpModule and IReadOnlySessionState interfaces, but the Session is always null on the AcquireRequestState event when the file is "static" and not IIS managed (like aspx, ashx etc).
If I use a custom HttpHandler, I get the session, but then I also need to implement how the content is sent to response. Edit: Since the user isn't downloading the file, I just want IIS to serve the file like it does with its StaticFileModule. The Handler/Module should really be a StaticFileModuleWithAuthorizationHook...
So I really want to do the following:
1. For request /topFolder/* : check session and licenses etc
a) If ok, continue serving file
b) If not ok, interrupt request, or just send FORBIDDEN in response.
Hope someone can help.
You should be able to handle this via the httphandler, the simple way is to use the built in methods to send the file down to the user if they have access.
This article (at the bottom) shows an example of how to do this.

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