I would like to create a image file upload tool. The tool when started up and would ask the user what directory they would like to monitor and upload files from. In the background the tool would then post securely to a web service of some sort.
Constraints solution should work on Mac and Windows computers. I would like to make the upload process pretty automatic with little user intervention.
Basically the question I have is what would you use to create application that either runs in the background or foreground to basically continuously uploads files to a web server?
I have a couple of thoughts:
HTML5 using web workers (concerns accessing local files not sure the best way to do that)
Silverlight (my guess is I would have to sign the application)
Java web start application (Signing application)
Flash (scared of this idea)
I can do the Java web start application easy enough. Both HTML5 and Silverlight are things that I would like to know. I really don't care about flash at this point.
In Java, you can use the JNotify library: http://jnotify.sf.net . It works on Windows, OS X, and Linux.
I don't know about C# or HTML5. HTML5 (last I checked circa July 2011) doesn't have a filesystem API. In reality you need an app that can be distributed so it can run in the background, so Silverlight is out of the question. If I am misinterpreting your problem, please tell me.
I would try to go with a signed Java applet if you can foresee the need for downloading as well. It is difficult to find a good download solution other then a signed Java applet. A signed Java applet let's you push things to the users filesystem allowing for upload as well as download.
Related
Need to create a service application that monitor all files being downloaded. I was thinking about using the file watcher class but some end users can change the download directory. Any idea would be great.
Monitoring file system is no indicative of download activity, as you already figured out. Browsers do not expose a cross-platform API to report download events. Browsers plugins do, but that requires the plugin to be loaded, enabled and you'll need separate plugins for each browser out there. So the only sensible approach is a filter driver. In fact the OS exposes a handy helper layer specifically designed for this, the Windows Filtering Platform. Of course, C++ and networking expertise is required. Detecting downloads from all traffic is left as an exercise to the reader.
If you want to monitor files downloaded on computers in an office environment, your best bet would be to install a proxy server.
I am newbie to the web programming. I have been working as desktop application programmer for the last 8 years. Now one of my projects is to create a web application using HTML 5 and some java script that can be live on the cloud as well as downloadable as a desktop application to work offline. I don't need any database to store any data. I am thinking of writing a C# win form application with a web browser control to load the HTML pages and the .js files.
My questions are:
Is it possible to achieve? if so, is there any other way than what I mentioned above?
What about the security concerns such as accessing the files(the html files, java script files, etc)? Whether this can be called into my application from the local hard disk?
If I can run it as a desktop application, how to make sure that the source code is not accessed by anyone in the client machine?
It's achievable, but why you would want to wrap it in a C# web browser control doesn't really make sense to me. With HTML5 you can define cache manifest files to create offline apps that run in any browser that supports it, no need to wrap it with anything as long as the client has a capable browser. They don't even have to know it's an offline app!
Not quite sure what you mean here with regards to security concerns. That's a massive topic. Just use common sense and realize that anything you store on their computers will be accessible by them (e.g. do not give them your public/private key pair or store any passwords or anything you don't want them reading in the files you're sending to them) and use a secure connection to send sensitive data back and forth between the client and your server.
You really can't prevent anyone from accessing the source code if it's on their machine. The best you can do is obfuscate it to a reasonable degree before deployment to make it harder on the person trying to read it.
Could you provide example of JavaScript function for starting up application installed on your computer from a web browser (eg google chrome 4). It particular if .Net APPs have any special simplifying this process apis of out there are some libs for such staff, please share link with us.
so how to create and store in run on start up programs a small local server which would handel some local urls like http://localhost/maAppServer/MyAppCalculator/Start for starting apps that have written in its config file their names and local urls on install?
So how to start up your C# .NET app\program from web browser?
I don't believe its possible in Chrome, starting an EXE on a users computer could be considered a security violation. Some ActiveX, and file:// links in internet explorer may work. Also, OneClick deployment may do something similar to what you are after (not exactly though I don't think, and I believe they require an add-in which may not be available for Crhome) http://www.15seconds.com/issue/041229.htm
I'm not sure what you're asking for. You can start an application on your computer just by linking to it in the HTML page. However, if you need to pass data to it, then it's a different matter altogether, although it's still simple.
An example is what www.nexon.com does with it's MMORPG, MapleStory. You log on to the website, and the web page starts the game after the authentication. Another example would be the magnet links on file-sharing sites.
You need to create a protocol handler, it can be in any language like C++/C# and register it on the client's computer. Like so - http://msdn.microsoft.com/en-us/library/aa767914(VS.85).aspx
Then, just use the protocol you built to pass on whatever data necessary. You can add a link that can be clicked, a button, Response.Redirect() from the server, whatever you like.
I have build an C# Winforms application which will need regular updates and patches in the future. To ease the update process for the users of my app I'd like to build an web-update class that looks for an update on my site.
What would be the most secure and reliable way to implement such a class, considering:
The site is build in PHP / Joomla
I haven't the foggiest idea how to program in PHP
All webserver directories are read-only by default (and only writeable by an FTP account I own)
The first and so far only idea that comes up to me is to create a file on my webserver that'll never be renamed, and in it I'll define the location of the latest version and number of it. The app will then be able to download the update from that path using the WebClient class.
However, if there's anyone with a better update-class idea that doesn't require an asp.net webserver nor webservices (already tried and failed on that one), I'll be grateful.
Edit:
I've tried the ClickOnce solution suggested by Gabriel McAdams, but on application startup I experience a "ClickOnce launch utility has stopped working" crash. So I'm again looking for a solution to update an application. For the moment, the answer of Kristian Damian is the most suitable.
I would look into ClickOnce Deployment.
Here is some of the text from that page:
ClickOnce deployment allows you to publish Windows-based applications to a Web server or network file share for simplified installation. Visual Studio provides full support for publishing and updating applications deployed with ClickOnce.
Maybe this link can help you:
http://themech.net/2008/05/adding-check-for-update-option-in-csharp/
I developed a Windows application in C# that does updates automatically over the Internet. After much grief, mainly because at that time I had very little experinece with Web development, I purchased a product that made it easy to update the application. If it is OK with StackOverFlow and you are interested, I can give you the URL.
To summarize, as we all know,
a) Silverlight is expected to be hosted by a browser, and runs in an isolated sandbox so that there won’t be any security issues
Silverlight don’t have direct access
to the file system, other than the
isolated storage area
There is no
direct way to open common dialog
boxes like File Save in Silverlight (Though Opendialog box is supported).
b) Silverlight can’t access local resources like a printer
What are the ways to go beyond the sandbox, so that I can host a Silverlight application locally, to read files and save them back if required, to hand over data to a printer, and so on..
Update:
Is full WPF is not an option for me? No. I'm also interested in a cross platform solution - for instance, you could host Silverlight in Mono Web browser control, so that you can run it virtually anywhere.
The idea is to re-use the same application that I'm building for web in my desktop as well, by providing separation of concerns at some areas - like persistence, resource access etc.
Scenarios:
1- Some kind of gadget container, with access to local resources.
2 - A desktop Silver light based media application
Update:
I just did a POC to enable me to access printer and save files locally, of course through a shell where I'm hosting my Silverlight application. If you wan't you can have a look at the post here in my blog
Two ways I can think about is,
Create a "Shell"
Host the HTML Page with Silverlight, in a Winforms desktop application, using a web browser control, and communicate to and fro using HTML DOM. Then I can request the hosted shell to do things like printing. See details here
Mono also has a web browser control - based on FireFox XULRunner instead of IE - not yet succeeded in loading Silverlight inside that. Another option might be using Webkit.
Embed a web server
Embed a light weight web server with in the Host application, and handle requests to perform such operations. You can probably define a protocol on top of HTTP for things like saving to a local folder, sending data to print etc.
Is a full WPF application not an option for your situation?
As you probably know Silverlight uses a subset of WPF so you may be able to change your application relatively easy.
A wpf app would be easier than having a web server etc bundled within your application.
You wont in the foreseeable future be able to have access to resources such as printer and files (apart from isolated storage) through Silverlight as you know.
You could have a seperate part of your app to upload files to the webserver then read these in your silverlight app from a service.
Depending on your printing requirements (e.g. if you just want to send everything to an office printer) you could send the informaton you wanted printed to a service that will then print it for you. However I am guessing you want each client machine to be able to print in which case this wont work for you.
I am attempting to also reuse a codebase for both desktop and silverlight. There are two options that I know of in addition to the ones mentioned
If you directly reference (instead of a project reference) a silverlight dll from a normal project, it should work. This would let you reference a silverlight dll for both projects.
Have two project files (one wpf, one silverlight) that point to the same set of files. You might have to have to use a few compiler flags here and there, but this should let you use the same files for both.