Develop Reference

SYNCH databases customization

Existing Application:
I have an existing distributed Windows Forms application which is developed using VS 2013 & SQL Server 2008. Application is communicating through web api's from various remote locations to the central database.
Requirement/Feature:
1. I have to add new feature that application may be run in offline mode if there is no internet connectivity. When application is connected to the internet it should SYNCH all the data automatically to the server. Also if there are any changes to the database server in central database it should be SYNCH to remote locations as well.
The synch mechanism must use the webapis to synch the data and database structure.
My Proposal:
I'm planning to use Microsoft SYNCH framework to add SYNCH feature but it can not be done through webapi's (It has to be done through API's as per client requirement).
Also we need complete audit/reporting of the SYNCH process and hence this can not be done without customizing the program for adding SYNCH feature and we can not use Micorsoft SYNCH framework.
My Question/Queries
Can anyone suggest the best approach to do this so that both data and architecture can be SYNCH?
Would be great if anyone has used the generic approach which may be used for all database tables?
Thank you very much in advance!!

Data Sync between local database and online database

I am developing a C# based window store app which has GUI developed using WPF.
The application's database is already on the Cloud through Windows Azure, but, I also want to have local copy of it through SQLite
Now, my question is:
How can I synchronize the data between Windows Azure and SQLite?

You can use Windows Azure Offline Sync. This tutorial may help you which states:
Offline support will allow you to interact with a local database when
your app is in an offline scenario. Once your app is online with the
backend database, you sync your local changes using the offline
features.
this video may also help support the tutorial

C# windows form app that can be accessed within the network

I'm a C# noob and i want to ask if it's possible for this kind of scenario:
I have a windows form app in C#, is it possible i will only install it in 1 computer(as a server) and it can be accessible from all the computers within the network? If it's possible can you please help me what i need to do, any reference/books/tutorials?
I already googled this but i think i can't find the correct 'search word' that's why i didn't get the desired search result.

Yes it is possible. Put the C# executable in a network UNC Path, and you can access it if you create a link on the destination desktops. XP SP 2 and higher by default can run it. If it has .NET 3.0 or 3.5 or 4.0 framework you may need to install the Runtimes for those frameworks, but .NET 2.0 should be fine with XPsp2. All the frameworks are downloadable from Microsoft's site.
Is this a database driven app or just a straight up stand alone?
You don't need any books, it should work just fine. But provide as many details as you can so we can steer you in the right direction.

You may have to do a large code overhaul to do this. Could you simply install it on one computer and remote login to that computer and access it?
You see the thing about network-accessed programs is that they have two parts--a client and a server. It sounds like you just have one piece. You would need to write a program that is a windows form and install it on all the machines. You would then need to write your server code that receives the data from the client over the network.
You would need to know about socket programming. Here is a book introductory tutorial of C# and sockets.
http://www.codeproject.com/KB/IP/socketsincsharp.aspx

I'm not 100% sure what you're asking, but hopefully this covers it. If not, please edit your question to be more specific.
You can generally run a WinForms application from a shared network drive/folder by copying the executable to that drive (and making sure that all users have appropriate access to that network location).
If you use an automatic installer, it should be possible to select a network share as the place to install the software. Automatic installers tend to also put things in the local registry (e.g. create menu items for the program, which go on the local computer always). In that scenario, you would want to create an installer that creates appropriate shortcuts/menu items on the local computer that point to the pre-installed executable on the network share.
You need to take care that the windows forms application doesn't write data to the network share, or if it does, that it does so in a manner consistent with multiple users accessing that data (in other words, keep in mind that all of your users will share that location).

Put it in a shared folder and access either by UNC path or map a drive to that location. You could also map the drive for all users with group policy.
Alternatively you could wrap your app into an MSI and install it via group policy?
Hope this helps :)

You should use a layered approach to your software design. Create a website to give users access to the application from multiple locations. Then create a service layer to give the website access to the desktop functionality that you require. WCF is a good service layer as it allows consumption through HTTP.

Writing a user mode filesystem for windows?

Is it possible to write a filesystem for Windows in pure usermode, or more specifically purely in managed code? I am thinking of something very similar to GMAILFS. Excluding what it is doing under the covers (GMAIL, Amazon, etc..) the main goal would be to provide a drive letter and support all of the basic file operations, and possibly even adding my own structures for storing metadata, etc..

Windows provides several approaches to building a user-mode file system for different purposes, depending on your storage location and features that you need to support. Two of them, Projected File System API and Cloud Files API were recently provided as part of the Windows 10 updates.
Windows Projected File System API
Projected File System API is designed to represent some hierarchical data, such as for example Windows Registry, in the form of a file system.
Unlike Cloud Files (see below) it does not provide any information about file status and hides the fact that this is not the “real” file system. Example.
Windows Cloud Sync Engine API
Cloud Sync Engine API (Cloud Files API, Cloud Filter API) is used in OneDrive on Windows 10 under the hood. It provides folder content loading during the first request, on-demand files content loading in several different modes, and offline files support. It integrates directly into Windows File Manager and Windows Notification Center and provides file status (offline, in-sync, conflict, pinned) and file content transfer progress.
The Cloud Files API runs under regular user permissions and does not require admin privileges for file system mounting or any API calls. Example.
Windows Shell Namespace Extensions API
While Shell Namespace Extension is not a real file system, in many cases you will use it to extend the functionality of the Projected File System and Cloud Files API. For example, you will it to add custom commands to context menus in Windows File Manager as well as you can create nodes that look and behave like a real file system (again, applications would not be able to read or write to such nodes, this is just a user interface).
Cloud Files API is using a namespace extension to show your sync root at the top level in Windows File Manager.

It's difficult. I'd take a look at some projects which have done some of the hard work for you, e.g. Dokan.

Yes. It's possible and has been successfully done for the ext2 filesystem.
Note that you will need to write your own driver which will require Microsoft signing to be run on some OSes.

Sure, you can abstract the regular file operations and have them running in the cloud (see Google Apps, Amazon S3, Microsoft Azure etc.). But if you'd like to talk to local devices - including the local HD - you'll have to use system APIs and those use drivers (system/kernel mode).
As long as all you want is a storage service -no problem. If you want a real OS, you'll need to talk to real hardware and that means drivers.

Just as a reference - our Callback File System is a maintained and supported solution for creation of filesystems in user-mode.

Please give reference/guidance to make a web application for managing all IT assest/devices

Please give reference/guidance to make a web application for managing all IT assest/devices .
Application consist of two component Web application and Windows .NET Application.
Client Windows .NET Application scan all active network & find all IT assests like printer,scanner & upload all data into the web application.
Now our team using Asp.net & c#
technology for this project.
Please give suggestion regarding the
client application & web application
interaction.
Suggest any library/reference
required for the project.
Is Microsoft sync frame work good for
client application.
Is Microsoft WCF will be a good
option for client & server
interaction(for making API).
How to scan active network for
finding devices by using client
application.

I will suggest you to go for a simple solution like
1. A windows application that takes care of scanning the entire network of computers from the installed computer and then sends the information to a web service
2. A web service to accept the assets list and then save them to the database
3. An asp.net application to display and catalog the indexed assets.
The part that will become somewhat complicated will be the assets discovery since it should be handled by the windows application. Your best bets are
1. to depend on the windows registry
2. to use the Windows Management Instrumentation (WMI)
3. If you dare you can dirctly program against the Netapi32.dll: NetServerEnum or similar low level win32 API
Hope this will help you to get started

Consider this approach:
Asset Catalog Service (WCF App). Its responsibility is to act as a repository for found assets. The service encapsulates the actual storage (database, etc).
Asset Finder (Winform app). Its responsibility is to scan all active network, find all IT assets and calls Asset Catalog Service to register the device. Asset Catalog Service will reconsile whether a device has not been registered (therefore will be stored), a device have been updated (therefore will be updated) or no change (therefore will be ignored). You may have multiple instances of Asset Finder running at the same time to speed up the discovery process. Asset Catalog Service or another service may be used to keep track the work pool of the asset finders.
The website (Asp.Net Web app). Its responsibility is to visualize the asset catalog. It queries Asset Catalog Service and display the result to the end users.
I can't see any obvious use case for using Microsoft Sync framework.
Unfortunately, I don't have any experience in writing any asset discovery algorithm. Others might be able to help on that point.
Hope that helps.

This is a bit off topic, but I would suggest looking at options from existing vendors that will meet your overall business requirements. Asset detection and management is not a simple task and creating an in-house application to do it is often a waste of time and money that could be better spent on core business needs or other IT support/resources. Purchasing software from an existing vendor will give you a much better solution than whatever you can code up in a week, a month, or even a year. If you are trying to catalog even a medium sized network with over 100 nodes then using an established system could end up being much cheaper than building your own. Here are a few examples of existing products:
http://www.vector-networks.com/components/network-discovery-and-mapping.php
http://www.manageengine.com/products/service-desk/track-it-assets.html
I haven't used either of them, but I have been down a similar route trying to create an in--house server monitoring and management system. We spent two weeks working on a prototype that was eventually scraped for a 3rd-party system that cost $1,000 a year. It would have cost us at least $10,000 to build something with 1/10th the features, let alone support and maintain it. Even just searching for a FOSS solution and then using that as the basis for your project (something like nmap) would be better than starting from scratch.
Best of luck!

Windows based application should be used to scan network and collect info about devices/assets available in the network. save those information in database.
look at following project to get and idea how you may scan the network http://sourceforge.net/projects/nexb/
the same database should be used by ASP .net app to be used for reporting purposes, you may also use it to group/tag/categorize various assets.
Also store scanned devices in separate "departments" depending on their IP schema.