I have a web app with asp.net mvc 5 on running on iis 7.5. I have a photo upload page that I made with DropZone (a javascript ajax upload plugin). In my asp.net controller during certain errors, I return an httpstatuscode of 500 with a status description with a descriptive error. DropZone then displays this descriptive error. Everything works as it should on desktop devices, however when used on an iOS device it displays a generic "Internal Server Error" message.
I'm lost at how to troubleshoot this issue. I've placed javascript alerts throughout my javascript code to try and figure out what the issue is but that didn't reveal anything helpful. I've tried using the MIHTool ipad app and the HttpWatchBasic ipad app to try and set breakpoints but that was not helpful either.
Is there a way to remotely debug an asp.net web app from an iPad? (I have visual studio 2013 premium) Or does anyone have any ideas what may be causing a different status code to be sent?
UPDATE: It appears that iOS devices ignore any custom xhr.statusText and uses the standard default statusText (i.e. code 500 is Internal Server Error). As a work around (which I hate doing, but since this is primarily for use on company iPads I didn't have much choice) I've returned a different 500 class code for each possible exception and then in the javascript code check the status code and assign my own custom error message in the javascript code.
Quickest and easiest way to see the actual exception is to turn off custom errors in your Web.config - you'll then be able to view the actual stacktrace on the iPad.
If you'd like to be able to debug the exception, you should be able to trigger it by accessing the site from the iPad by hitting your windows development machine while running in the debugger. You'll need to configure IIS express to allow remote connections (editing application host.config), adding a urlacl, and opening the Windows firewall if necessary. There are numerous guides in setting this up online.
If you want to actually debug the JS in mobile Safari, this is possible from the Mac version of Safari - see http://webdesign.tutsplus.com/articles/quick-tip-using-web-inspector-to-debug-mobile-safari--webdesign-8787 for details.
Related
Umbraco 7.6.6, running under IIS 8.5 on fully patched Windows Server 2011 R2 Standard, 64bit.
Our content editors notice that often when they create a new article (which has some graphics specified) the system hangs after they try to browse to a different article... or indeed anywhere in the front-end site, too. It only affects them; other users are still able to browse and/or create content.
F12 dev tools shows that browser is pending the result of this type of call:
http://whatever.com/media/1101/thumbnail_pmc-1x2.jpg?width=500&mode=max&animationprocessmode=first
If I try to view that thumbnail without the querystring data, it loads instantly... while the first call is still hanging in it's unresponsive tab:
http://whatever.com/media/1101/thumbnail_pmc-1x2.jpg
DEBUG level Umbraco logs just show this:
2017-10-10 17:02:53,120 [P2816/D6/T57] DEBUG Umbraco.Web.UmbracoModule - Begin request: http://whatever.com/media/1101/thumbnail_pmc-1x2.jpg?width=500&mode=max&animationprocessmode=first.
No errors in the umbraco logs, no errors in IIS logs, nothing in event viewer.
Best I can tell, something is going wonky in the browser. Can anybody please advise on how I can troubleshoot further?
Thanks!
I'm tasked with fixing a bug on the mobile version of a project I just came on (and still learning my way around it). Its a heavy use 24/7 kinda job, so not keen on the trial and error guess/upload/test style of debugging.The bug is that almost none of the controls, particularly tabs, respond to user "clicks" on the ipad. The app was developed in asp.net MVC4 and I work on windows 7 in vs2012.
We are not a mac shop, but still need to support the Ipad and phone.
This is probably a simple question: but my searching keeps taking me
here: iOS6 - removed console log for IPad - how to use web inspector on windows?
and here: Accessing iOS Safari Web Inspector from Windows Machine.
I need a way to gather actually diagnostics, like what would be available in web inspector, without having to acquire a mac.
Use weinre. It runs a webserver that that can repond to a bookmarklet or <script> to run a remote inspector.
weinre is a debugger for web pages, like FireBug (for FireFox) and Web Inspector (for WebKit-based browsers), except it's designed to work remotely, and in particular, to allow you debug web pages on a mobile device such as a phone.
Get NodeJS, NPM, and a webkit-based desktop browser to run it.
Homepage: https://people.apache.org/~pmuellr/weinre/
Docs: https://people.apache.org/~pmuellr/weinre/docs/latest/
To install with yarn:
yarn add --dev weinre
then because it's no longer maintained, you may get TypeError: mime.lookup is not a function when you try to use it, then you have to edit node_modules/connect/lib/middleware/static.js and change require('mime') to require('mime-types') on line 21 (thanks). Then start with
yarn run weinre
If you now open the url showed there, you'll see the bookmarklet you can use etc. (Note: If using this from other computers, you may have to open local firewall ports, and if debugging a https site you may have to add a reverse proxy with cors headers.)
I have an app that takes a screenshot of web pages and creates a resized image. The app is basically loading a web page that calls an ActiveX to load a web page using IE resources and take the screenshot. This app has been running on a Windows Server 2003 without any problems for a couple of years.
But now that I have upgraded the server to Windows Server 2008, the screenshot action is timing out. From tests I can see that it successfully takes a screenshot of any web page hosted on the Internet... except pages hosted on the same server.
Whenever it tries to capture a page loaded on a site hosted on the same server as the app, it times out. ESC is disabled and it seems that all other permissions are ok, ie: it works for remote pages but for home pages.
Any ideas as to what can be causing this and how to fix it?
After further testing I have narrowed down the reason for failure being due to the page being popluated from a MS-SQL database record on the same server as the one taking the screenshot. The same page generated on a remote server captures ok. I have further established that the error is not peculiar to the ACASystems DLL because it also affects another DLL for creating MHT files from web pages. This DLL (Chilkat.MHT) also uses IE to load and assemble the web page on the fly and then saves it as a.mht file.
So the problem is more related to IE assembling web pages from MS-SQL while running ActiveX. But to resolve this enigma?
Maybe a routing issue (DNS/hostfile..) ? Does the page loads on local session with IE ?
There is no solution for this without editing the ActiveX code. Since the DLLs in question are third party resources, such editing is not possible.
After testing 3 different ActiveX that load a web page that either take a screenshot or save as .mht, it was found that they all failed when loading a page that was querying SQL on the same server. After contacting the 3 DLL developers we were informed by all of them that their ActiveX has no impact on MS-SQL.
Unfortunately, our tests tell us otherwise. At this stage we are left guessing however this article about in-process vs out-process execution may be related.
The workaround for us to solve this problem was to assemble the page to be captured from request queries passed to the page rather than populate from SQL queries. This alternate works perfectly.
I have a strange issue with an Asp.NET MVC application.
Using Asp.NET MVC 3 Preview 1 on IIS 7.5 - Integrated
After building the application everything runs fine. Then after some random amount of time (or sometimes after updating a view or js file) the application dies.
Meaning, requesting the root page, I get the 403 error and requesting any other page I get a 404 error.
After a rebuild everything works fine again for a little while until it dies again.
I am seeing this on two different development machines. Also, I have another application which is very similar (MVC 3, IIS etc) on both dev machines and this one runs without problem. I have inspected the config files in detail and cannot see anything of notable difference.
Does anyone know what could cause an application to die or where to look for further information? (I can still access elmah.axd though no information is there).
There's not much to go on here, but the 403 and 404 are clues that at least ASP.NET routing is not working; 403 is coming back because the web server thinks you want to do a directory browse, 404 because your request doesn't have a valid corresponding resource.
Since you are using the new version of MVC, I would suspect the issue may lye there. When you get the error condition, can you browse to a regular .aspx page? Does it execute server side code correctly?
You have the site hosted in IIS 7.5, not just the built in Visual Studio web server, right? Is it possible to turn on monitoring/event logging to see if IIS is taking a hit?
I apologize for not having any actual answer, sounds like you have a tough issue to debug.
Good Luck!
I am unable to show images in CR reports. I'm developing a MVC 2 project in VS 2008 with Crystal Reports that comes with it (10.5). Everything works fine, except for images. I can see them in the preview mode within the CR designer, but not when the app is deployed, which means I am loading data OK but something's wrong with IIS and/or routing.
When running the app, images appear with the red cross and if I navigate to the following url directly I get a 404 error.
http://localhost:1234/CrystalImageHandler.aspx
I think my problem is similar to the one here but that workaround doesn't seem to work for me.
I should also comment that I'm using the Areas feature within MVC.
EDIT: Forgot to add: When exporting the report to PDF the images are shown ok.
I don't know much about crystal reports, but is there an Http Handler? If there is and you are running IIS 7 on the live server, is the handler registered in the web.config under both system.web/httpHandlers and under system.webServer/handlers?
I forget to register the handlers under system.webServer/handlers for our IIS 7 server sometimes and we were having a similar issue with the Microsoft Charting Controls.