Sony Arouje

Last couple of days I was working on Node js REST service running in one of my Raspberry Pi. The idea is to do certain stuffs remotely via mobile devices. Later I will write a post explaining the project in detail. I completed Phase 1 of the application running in Raspberry pi. So next task was creating a mobile app, I decided to use Cordova with VS 2013 Multi Device Hybrid app template.

Yesterday night I started working on the Hybrid app in VS 2013 for Windows 8. First thing I wanted to test was the connectivity to the REST service running in Raspberry pi. I used Angular js $http to connect to the REST service. To my surprise what ever I do, the app is throwing error while doing http post with status 0. The same code works successfully if I run as a web app.

I spend a hell lot of time to figure out the issue but no success. Then I decided to use fiddler to test the traffic, when fiddler is running the app could able to communicate with the REST service. I got a hint, when we run Fiddler in Win8, it adds apps to AppContainer Loopback exemption. If I exempt my windows 8 app then http request starts failing. This stage I realized that, the error is because of some app configuration issue. Also in VS Java Script console I could see the error as shown below.

XMLHttpRequest: Network Error 0x2efd, Could not complete the operation due to error 00002efd.

All my google search return nothing. After a long hours of desperate research I came to know that to access private network I need to add Private Network capability to windows 8 app. But I didn’t know how to add it for Hybrid app as there is no Capabilities section in the config.xml. Some more search leads me to the Faq page of Multi device hybrid app template. As per the FAQ page we can override the default AppManifest.xml as shown below.

1. Create a Package.appxmanifest file under res/cert/windows8. Create a windows8 solution folder if not exist.

2. Open the project folder and go to bld/windows-AnyCpu/Debug and open AppxManifest.xml in notepad, copy the content and paste it in the above Package.appxmanifest file.

3. Double click on Package.appxmanifest file then goto Capabilities tab and choose ‘Private Networks (Client & Server)’.

4. Save it and run the app again, this time it worked I could connect to my Node js REST api.

Hope this will help some one to solve the XMLHttpRequest issue.

Happy Coding…