Hi akaKin,
Node.js is server-side programming model for Windows Azure platform, it is not used for client-side application. For your scenario, if you want to access Windows Azure storage (like table, blog storage...) in your windows store apps, you can consider using
the Windows Azure REST API or the encapsulated Storage Client library for .NET and windows runtime. Here are some threads mentioned this:
#Directly access Azure Storage thru Store App
http://social.msdn.microsoft.com/Forums/en-US/winappswithcsharp/thread/95046795-c645-4580-843e-25b684670b9a'
#Getting Access to Azure Blob Storage from WinRT app
http://stackoverflow.com/questions/15900450/getting-access-to-azure-blob-storage-from-winrt-app
#Windows Azure Storage Client Library for Windows Runtime
http://blogs.msdn.com/b/windowsazurestorage/archive/2012/11/05/windows-azure-storage-client-library-for-windows-runtime.aspx
Also, for the storage client library, since it is naturally .NET based, to use it in Windows Store javascript app, you can first encapsulate it in a Windows Runtime library (created via C# or VB.NET):
#Walkthrough: Creating a simple component in C# or Visual Basic and calling it from JavaScript
http://msdn.microsoft.com/en-us/library/windows/apps/hh779077.aspx
In addition, if you have Windows Azure Web application, you can also consider host a custom REST service (WCF) at server-side which use windows Azure storage API to access the storage items. Then, your windows store apps or other client applications can
use your custom REST service instead of using those built-in API or libraries.
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