I'm programming a very simple Qt-based application which will be interfacing some website. That website requires user to login with username/password and solved Captcha. Because of that Captcha, I decided to use QWebKit and just display the website for the user (and intercept cookies in my app). It works almost great. Almost, because I'm having a really strange problem.
On Linux my app worked like a charm. On 64bit Windows 7 (32 bit build with VS 2010) - it worked without problems too. But the same binary has a very strange issue under 32bit Windows 7. It works, but does not display Captcha images making logging in impossible. Of course, I used Dependency Walker and ensured that all the DLL's are accessible.
The Captcha is not a popular reCaptcha or something, but Minteye slider Captcha (BTW, in my humble opinion it is quite easy to solve by a computer). As you can see at the bottom of the page I linked to, this captcha downloads a series of images and user has to select the "correct" (ungarbled) one with a slider.
The problem is, that for no apparent reason, my app just doesn't show these images on 32bit Windows 7, while on 64bit version everything works. The code I'm using is very simple, but I'm posting it anyway:
loginView = new QWebView();
QWebPage *page = new QWebPage();
manager = new QNetworkAccessManager();
loginView->setPage(page);
page->setNetworkAccessManager(manager);
jar = new QNetworkCookieJar();
manager->setCookieJar(jar);
page->mainFrame()->load(QUrl("http://site.to.open"));
loginView->show();
I verified with Wireshark that these images are indeed being downloaded from the server. I even changed user agent string to hardcoded one to be sure that the server doesn't mess up something only for for 32bit windows 7. Unless I'm missing something, the dialogue with the server is identical and the problem is on client's side.
The only thing that differs (and I'm pretty sure is connected to my problem) is behaviour of WebKit when trying to navigate to specific URL via developer tools (one can enable them in QWebKit, so did I). When I open the Javascript console for login page and enter:
window.location = "http://www.google.com"
It works on all my platforms. But, when I enter the address of one of the Captcha images:
window.location = "http://img2.minteye.com/slider/image.ashx...
Results vary. On Linux and 64bit Windows 7 it works and I can see an image. On problematic 32bit Windows 7, WebKit shows error Frame load interrupted by policy change and that's all. I have no idea what that error means and what "policy" changed. Google search didn't help me - I found posts by people complaining that they see this error, but nobody explained what causes it (WebKit source isn't super helpful too). If somebody knows, I might be able to get a workaround for my problem.
I'm also very courious, why this problem is present only on 32bit version of Windows 7.
Seems like this is/was a bug in QtWebkit implementation, you can read more about it here:
https://bugs.webkit.org/show_bug.cgi?id=37597
Which version of Qt and QtWebkit are you using ?
It might be a good idea to try a newer version of Qt & QtWekbit.
If it helps in any case here is the code in Webkit which shows this error:
http://src.chromium.org/svn/branches/WebKit/472/WebKit2/WebProcess/WebCoreSupport/qt/WebErrorsQt.cpp
This is not a bug.
What happens is that this image was generated dynamically, probably Headers were misconfigured.
the Frame load interrupted by policy change occurs because the WebView tries to open something that is not "text/image" (is not supported).
You should use this ( https://stackoverflow.com/a/16782607/1518921 ):
//replace [QWebView] by your WebView
connect([QWebView]->page(), SIGNAL(unsupportedContent(QNetworkReply*)), this, SLOT(downloadContent(QNetworkReply*)));
...
void [main class]::downloadContent(QNetworkReply *reply){
//Replace "[main class]" by "Class" having the signs used in WebView.
[QWebView]->stop();
//solution: stop loading --replace [QWebView] by your WebView,
/*function to donwload*/
}
At this point if you have a download manager, it will ask to save the image instead of opening it, because the content is not supported.
Solutions:
What you can do is try to fix image headers.
if your server is not then there will be, then you will have to parse the header Content-type and see what type it is trying to send, having kind of content you will have to reimplement the QWebPage:
virtual bool extension(Extension extension, const ExtensionOption *option = 0,
ExtensionReturn *output = 0);
virtual bool supportsExtension(Extension extension) const;
Good luck.
Related
We have built a WebDav Service with your Engine and have a one problem when we create a new Folder or File:
The new folder / file is created successfully, but not showing in the Windows Explorer. Only if you press F5, the new folder / file is showing (and the name is already selected to be edited).
This behavior is reproducible even with a blank WebDav Solution.
We can reproduce this on Windows 7 and Windows 8 (8.1) using WebDav .NET Server 3.8 and the latest 3.9.
Is there a way to get around this “refresh-problem”?
I solved this issue but clicking in the folder explorer at view > options > then i restored to default and everything is back to normal.
I assume this issue is in Windows Explorer on a single computer. Most likely the WebDAV server-side code is failing with with some exception. Here are some ideas how to detect what is wrong:
Unmount network connections executing 'net use * /DELETE' in a command prompt, this will unmount WebDAV connections too and simulate 'clean' environment.
Retry reproducing the issue and examine your WebDAV logfile. By default it is located in /App_Data/WebDAV/Logs/ folder. Are there any exceptions in it?
Use Fiddler tool or any other debugging proxy to capture and examine HTTP requests. Are there any failed requests?
In case you are creating a folder/file on one computer using Windows Explorer (Microsoft Mini-redirector driver) or IT Hit Ajax File Browser and expect the files list to refresh automatically on another computer this would not work. Mini-redirector does not support any notifications from server and WebDAV does not submit any notifications, you need to refresh the files list manually to see the new items created.
I found this video on Youtube that explains in very much detail how to fix this problem: https://www.youtube.com/watch?v=UUiCPsQquqc
It is a bit lengthy, so I'll just quickly sum it up here:
The reason for these problems are one or more (broken) Shell Extensions that prevent the refresh of the Windows Explorer
To fix it, open up regedit.exe (requires admin privileges), do a search for the Registry Key "DontRefresh". If it is "1", set it to "0". There might be multiple matches for that Key, so repeat until all Keys have the value "0".
This might not work immediately, you may have to kill and restart your explorer.exe process (easiest to do with the Task Manager). Or you can simply reboot your computer. In my case, it worked immediately.
According to the video, the Keys should only be located under HKEY_CLASSES_ROOT/CLSID, but in my case I could only find such Keys in HKEY_LOCAL_MACHINE/Classes/Wow6432Node/CLSID.
I figured it makes most sense to simply search the complete Registry, it does not take very long.
I tred a lot of hacks, from scanning the system, to recreating the profile to hacking Registry keys and hives.
Finally what worked for me -
Right click on desktop
Select Personalize
Click Themes
Click Change desktop icons
Click Restore default & OK
And instantly it began to auto refresh with a new folder, rename, delete, copy, etc.
I'm a C++ programmer, but I'm a newbie in Flex. I'm developing a Flex 3 application for a social network using the FlashDevelop. For debugging I'm using the stand-alone FlashPlayer (10.3 debug) downloaded from Adobe. The application is a simple audio player which shows artist/album images.
The application worked properly on both local computer and remote server until I made some layout changes in Main.mxml. I added some HBoxes and changed Image placement. After that the application still works on my local computer, but it doesn't work properly after I upload it to a server.
Application buttons are not highlighted on over/out/click events, images loaded from the Internet are not displayed, text changed dynamically is not displayed, but when I click buttons a sound file is loaded from the internet and starts playing. It looks like some events which are responsible for components displaying are not dispatched, because some part of functionality not related to displaying still works.
To make sure that this is not a server problem, I rolled back to the previous revision. All works fine.
I suppose that this is a known issue, but I have no idea what is the reason.
Could anyone please help me to resolve the issue?
Thanks.
UDP: I observed the issue in IE and FF, I didn't test Opera and Chrome.
Are you tying to access the pixel data of the images in the new version? If so, that might be the problem, as pixel data for loaded images is not (always) accessible so that might throw a security error, which in turns breaks the rest of the interface.
Also, did you try running the remote version in the debugger? If so, is there any exception being thrown?
And no, it's not a known issue, it's the kind of annoying and hard to debug error that you sometime get when using the Flex SDK.
SHORT VERSION: I have a Flex app that uses Salesforce.com's API. I am trying to deploy it to a remote server but keep getting "Error during login process." when I try to have it log in to salesforce's servers. What gives?
LONG VERSION (maybe someone finds this useful later): I have a flex application that's an add-on for salesforce.com
If I upload it as a static file to salesforce and then embed it in a visualforce page, it works fine. This method uses "loginBySessionId" rather than loginByCredentials.
I would like to be able to run it outside of salesforce's servers. IE, I would like to host the app on my own server and have people enter their credentials in the app and have it login to salesforce's servers. This way, if someone wants to try my application, they do not have to be salesforce administrators and do not have to install the app into a visualforce page.
Here's where the trouble is. If I enter my login information and run it from the compiler, it connects and loads the right data. If I export it as a production release, it still runs fine. However, if I either upload the release files to my own server, or if I transfer them to another computer and run them locally, i get an "Error during login process" Seems some others have had similar issues, but no solutions and nothing new.
Weirder still, if I transfer the project files to another computer and recompile them, it suddenly works. So basically, seems like I have to recompile the app for each computer I plan on running it on, but that's not practical. Even still, I don't see how that could possibly be making a difference, compiling on one vs the other. And yes, same versions of flash, same versions of Flex.
Does anyone have any suggestions on how to resolve this? Am I just misunderstanding something with how to deploy flex applications or is this some screwy thing with the salesforce API and there's a workaround?
As one added thing that makes this problem particularly frustrating is that I can't use the debugger because if I compile it on another computer, it works, so in order for me to get the error I have to build, then transfer to another computer. I feel like this could be a key to the problem, but I'm not sure how.
Here is some applicable code, pretty basic:
<flexforforce:F3WebApplication
id="app" statusChanged="statusChangedHandler(event)"
loginComplete="loginCompleteHandler(event)"
loginFailed="loginFailedHandler(event)"
sessionExpired="sessionExpiredHandler(event)"
serverUrl="http://na9.salesforce.com/services/Soap/u/19.0"
requiredTypes="Account,Contact,Opportunity,Lead,Task,User" />
protected function loginClickHandler( event : MouseEvent ) : void {
_username = 'LOGIN#LOGIN.COM';
_password = 'PASSWORD+SECURITY_TOKEN';
CursorManager.setBusyCursor();
app.loginByCredentials( _username, _password );
}
To clarify, you probably need something like this on initialization :
flash.system.Security.loadPolicyFile("http://na9.salesforce.com/services/Soap/crossdomain.xml");
The reason it works when you compile it is that a lot of the default security is not applicable when on same machine as compiled. Heck, you can even access the hard drive in paths (like a relative URL path to an image on the hard drive) - try running the swf on another computer and bam- no go.
This is an excellent indicator you're hitting a player / VM security issue :)
I'm new to web development so please, could you help me to understand if I'm working in the right direction?
There will be a webpage intended for our customers (not intranet) from where they can print labels. Some of the larger customers will have special label printers where configuration and printing using COM-port is the only acceptable option. Basically we have very limited knowledge and control over their environment.
The web-page itself will be a pretty simple html-page or more complex AJAX.
After the customer inputs all the data and happens to chose this type of printing we have following tasks:
1) get data about the printers on the customer's system installed to a comport and if possible get printer settings (like paper size and orientation). Ideally would like to be able to adjust the settings, but if it is a pain can just put into requirements that your printer must be installed to COM1 and configured correctly.
2) send commands and read answers and send PCL code to the selected com port
As I understand I'll need to install something on the customer's machine to be able to talk to com port and get any settings. Just HTML+Javascript are not capable of doing that. Right?
I found RXTX library which seems to communicate to com port on most platforms. Can it be called from JavaScript or I still need to do a Java plugin? Are there technologies other than Java plugin that would solve the task?
The web-page will be used in different environment - platforms and web-browsers. We would like to minimize the number of customized solutions. Will Java allow us to do the same plugin for all environments with minimal customization?
If we require the user to install a plugin will the user be prompted with our credentials to confirm the installation? Will our web-site require higher trust settings?
Thanks for you help!
Well, I've had to do this in the past. Here is what I did and the circumstances
1) I knew that our customers were in a windows environment so I wrote win32 software to handle the printing.
2) I created a file format to be read by the win32 software that allowed me to specify print parameters and the label data. XML works ok for things like this.
3) My web app created a file in the format used by the win32 software and returned it to the user when they clicked on the "Print Labels" button. The file extension on the file returned was registered by the installer of the win32 software. That means when their browser looked for a default app handler for that file, it found my win32 software.
Bottom line is that the browser is handing off the printer communications to a native application instead of talking directly to the printer.
Obviously you need to be able to dictate your end user's are using a windows machine (or mac or whatever you can write native code). Associating a file extension with my program and returning that file to the user was the key to making the process work for me.
Whether your native code sends pcl directly to the printer or translates into a print api (like the win32 api as mine does) is another consideration.
Another approach you could consider is instead of sending PCL codes, you could create a PDF of the document. Format the document to the size and orientation of the label printer. The user will still have to hit the print button, but that might work. I have done this for printing to bar code printers and it works fine. Sometimes getting the margin and orientation correct is a little tricky, but that can be figured out.
Trying to print an ASP.NET Charting control behind the scenes in my web app. I think it is a permissions issue with the printer as everything is ok up until the point where my code calls:
chart.Printing.Print(false);
bool finished = false;
while (!finished)
{
finished = File.Exists(settings.GetValue("statusfile")); // file which indicates document was printed
System.Threading.Thread.Sleep(1000);
}
At this point the page just freezes (or continues to load endlessly - infinite loop!) Understandably this is happening because I am 100% relying on the document being printed. I do intend to add a timeout, however, at the moment I am just trying to figure out why exactly the document is never being set to the printer!
I have given the account (which the AppPool is running under) permissions to all the relevant folders and even the pdf printer itself...Still nothing.
Am I missing something? Is there any issues with printing on the server side via ASP.NET? I have encountered some issues doing this via WindowsServices in the past not sure if it is a similar problem with ASP.NET websites.
Update
As suggested I updated the AppPool to give myself (admin) permissions and it is the same issue. So by the looks of things the job is never being sent to the printer. I can't seem to figure out why though...
Probably should have mentioned this in my original post....but I am invoking the printer through a referenced DLL, this code is not being called directly from my application (incase it matters). Also this runs fine on my Development machine which is running Windows 7 IIS7.0 where as the server is running Windows 2003 server with IIS6.0.
Update 2
I removed the while loop and just left in the chart.Printing.Print(false) line and turns out the document IS being sent to the printer. So the issue must be with the settings file not getting written which is why the loop never breaks out!
To isolate if this is indeed a permissions issue, you could try running the application using the Visual Studio web development server, which will run under your credentials. Or if that's not an option, temporarily change the IIS app pool so it uses your credentials. If things still do not work, you may have another issue. I'm not sure which charting library you're using (is it the newish Microsoft one?), but maybe Print wants to show a printer dialog.