I wonder if any p2p filesharing app exists (or a plugin) which can be configured to scan all locally existing files and identify them (hash, or PUID for audio, etc) so when the user searches and chooses many files at once it would download only non-existing files.
I have been googling a while but havent found anything in this direction.
Anybody got some links about research and development ?
To be honest, I have never heard of a framework offering all those functionalities. Most often, people build their applications on top of existing P2P frameworks.
P.S.: I have been around P2P systems for a couple of years now.
Related
First of all, I'm not really sure if this question goes here in stackoverflow or if I should ask it on another place. Please if that's the case, indicate me in the right way :)
So, for context, this is an app that I was asked to develop for my job. At first I thought in doing a webapp and host it inside the company servers and domain (intranet), but it isn't possible due to external issues that I can't control.
Is there another way to achieve this? The app must have a database and should be accessible for a bunch of users at the same time.
Of course we want to spend the least amount of money possible to make this happen. Also, using a workstation of our own to host everything is not possible either.
Edit: I didn't finish developing, but for now I'm developing it in Python Flask.
The number of users is small really, just up to five people.
OK - I guess a lot of what you'll get in response to this is your definition is too vague. Things such as scale, number of users, programming languages used to create the web app etc are important when talking about hosting.
However, for me, there are three very good options out there for free hosting, up to a certain amount of traffic.
1.) Heroku - Heroku.com
A world known web hosting platform. You can publish code through GitHub, and it has some extensive coverage for different types of web apps. Definitely worth a look.
2.) Netlify - netlify.com
Similar to Heroku, but used by some major companies. Allows you to host for free to a point, and is relatively simple to get started with.
3.) Vercel - vercel.com
A bit more technical in my opinion - but again, very similar to the above two and has a free tier.
All three are great options, and I'd recommend looking into them in more detail to see what option is best for you. Can't go wrong with any of them.
I had a similar problem: A Python-Flask-SQLite app for me and my office pals to use together.
The solution was creating one .exe file with pyinstaller, hosting this and the database files in a network drive (one that everyone that will use the app has access). As everybody (~10 people) sees the same db, things works fine!
I maintain the website for my daughter's school. Historically I used our service provider's webftp interface to make edits in-place through their web-based GUI, which worked well for the small edits I typically need to make. They recently disabled webftp for security reasons, leaving ftp as the means to modify web pages and upload documents. Yes, I know FTP isn't very secure itself, but that's another story.
I have used wget to pull down the site and have built a git repository to manage changes. As I make changes, I want to upload the new and modified files to the website. Ideally I would only upload the new and changed files, not the entire site. My question is how do I do this?
I have found wput, which looks promising, but its documentation is not clear about which directory that wget created is the one I should recursively upload, and what the target directory should be. Since we are talking about a live site, I don't want to experiment until I get things right.
This seems like it should be a common use case with a well-known solution, but I have had little luck finding one. I have tried searches on Google and Stack Overflow with terms like "upload changed files ftp linux", but no clear answer pops up like I usually get. Some recommend rsync, but the target is on the service provider's system, so that might not work. Many variants of my question that I have found are Windows-centric and of little help since I work on Linux.
I suppose I could set up a target VM and experiment with that, but that seems excessive for what should be an easily answered question, hence my appeal to Stack Overflow. What do you recommend?
maybe this answer helps you : https://serverfault.com/questions/24622/how-to-use-rsync-over-ftp/24833#24833
It uses lftp's mirror function to sync up a remote and local directory tree.
I also used mc's (midnight commander) built in ftp client quite a lot when maintaining a site.
You should use git with git-ftp. It is generally a good idea to use a VCS by any project...
I have a number of Windows servers at work that are used for staging web sites for clients while they are being created.
I wanted to start using versioning on them so that when we work with outside vendors on a project, if/when they overwrite my work, I'd like to be able to go back and get the version before.
My question is that I think I'm not looking for the correct terms in searching for information, but what kind of resources are there to learn how to install the software for versioning or a site to help me get started.
Any and all suggestions would be appreciated.
Steph
Since your development workflow can be decentralized (as in "there isn't always one central repository), DVCS tools, with their common tasks described here) can be more adapted.
Git-Scm
Mercurial (see HgInit.com for a very good tutorial like the kind you are after)
Plastic SCM (which has a DVCS nature)
I have recently installed Ubuntu Linux on my machine. This machine is on pretty much all of the time and houses my music collection. I have looked at various solutions for a central repository for music and each one is lacking in one way or another. I have done some .net programming and thought this would be an ideal project to try on MONO.
My question is this. What parts of an application are needed for streaming music around my house. I would like a web front end but other than that I'm not really sure of the parts needed to form this sort of application.
Any insight into this type of application are much appreciated!
No need to re-invent the wheel
http://en.wikipedia.org/wiki/Digital_Living_Network_Alliance
http://manuals.playstation.net/document/en/ps3/3_15/settings/connectdlna.html
http://www.obsessable.com/feature/home-media-streaming-101-dlna-explained/
Since you are running linux, I suggest you try http://mediatomb.cc/
My boss has come to me and asked how to enure a file uploaded through web page is safe. He wants people to be able to upload pdfs and tiff images (and the like) and his real concern is someone embedding a virus in a pdf that is then viewed/altered (and the virus executed). I just read something on a procedure that could be used to destroy stenographic information emebedded in images by altering least sifnificant bits. Could a similar process be used to enusre that a virus isn't implanted? Does anyone know of any programs that can scrub files?
Update:
So the team argued about this a little bit, and one developer found a post about letting the file download to the file system and having the antivirus software that protects the network check the files there. The poster essentially said that it was too difficult to use the API or the command line for a couple of products. This seems a little kludgy to me, because we are planning on storing the files in the db, but I haven't had to scan files for viruses before. Does anyone have any thoughts or expierence with this?
http://www.softwarebyrob.com/2008/05/15/virus-scanning-from-code/
I'd recommend running your uploaded files through antivirus software such as ClamAV. I don't know about scrubbing files to remove viruses, but this will at least allow you to detect and delete infected files before you view them.
Viruses embedded in image files are unlikely to be a major problem for your application. What will be a problem is JAR files. Image files with JAR trailers can be loaded from any page on the Internet as a Java applet, with same-origin bindings (cookies) pointing into your application and your server.
The best way to handle image uploads is to crop, scale, and transform them into a different image format. Images should have different sizes, hashes, and checksums before and after transformation. For instance, Gravatar, which provides the "buddy icons" for Stack Overflow, forces you to crop your image, and then translates it to a PNG.
Is it possible to construct a malicious PDF or DOC file that will exploit vulnerabilities in Word or Acrobat? Probably. But ClamAV is not going to do a very good job at stopping those attacks; those aren't "viruses", but rather vulnerabilities in viewer software.
It depends on your company's budget but there are hardware devices and software applications that can sit between your web server and the outside world to perform these functions. Some of these are hardware firewalls with anti-virus software built in. Sometimes they are called application gateways or application proxies.
Here are links to an open source gateway that uses Clam-AV:
http://en.wikipedia.org/wiki/Gateway_Anti-Virus
http://gatewayav.sourceforge.net/faq.html
You'd probably need to chain an actual virus scanner to the upload process (the same way many virus scanners ensure that a file you download in your browser is safe).
In order to do this yourself, you'd have to keep it up to date, which means keeping libraries of virus definitions around, which is likely beyond the scope of your application (and may not even be feasible depending on the size of your organization).
Yes, ClamAV should scan the file regardless of the extension.
Use a reverse proxy setup such as
www <-> HAVP <-> webserver
HAVP (http://www.server-side.de/) is a way to scan http traffic though ClamAV or any other commercial antivirus software. It will prevent users to download infected files.
If you need https or anything else, then you can put another reverse proxy or web server in reverse proxy mode that can handle the SSL before HAVP
Nevertheless, it does not work at upload, so it will not prevent the files to be stored on servers, but prevent the files from being downloaded and thus propagated. So use it with a regular file scanning (eg clamscan).