i try to create a web site where it will provide an option to the user to upload a pdf file. I want this pdf to be saved on the server with specific url. For example:
The user select the title.
The user upload the file.
I want after these actions the file to be accessible via a specific url/name_the_user_give.
I saw that the Spring MVC provides very easy interface for file uploading.I already see many tutorial about this but my problem is how can i save the paper into a server.Also i want the pdf to open by the browser's tools.Can anyone give me directions?
To save the file on server path you simply needs to write the file stream to the path described by
request.getServletContext().getRealPath("your directory name here");
and then create the file using the real path you get.
And to show the pdf file using browser plugin, you should use following in your controller method.
#RequestMapping(value="url to map", produces={"application/pdf"})
Hope this helps you.
Cheers.
Related
I am using Spring to create a web application in which a user can upload a zipped folder containing an index.html file along with all it's resources(pretty much like an Adobe captivate generated webpage). The user should be able to request the uploaded web pages in the form of inner web pages.
I can only go as far as unzipping the folder itself, but I have no idea how to launch the index.html present inside the zipped folder.
How do I achieve this?
Quite honestly Spring has no restrictions or advantages over
displaying your subpages inside another page. However you can use Spring MVC to dynamically serve the web pages from the uploaded folder.
More over you have to play the tricks from browser side. Going with iFrame seems to be the best option from client side, though there are many other options. Please check this thread.
You can write some smart APIs in SpringController which accepts the folder path or folder name as parameter, picks the necessary pages from the requested folder and serves the user.
Another approach could be to use a headless browser for the server side rendering and give the output as screenshots to client. This can render the pages server side. Please check this thread for more details.
I hope this helps you!
If i have a filename for a local file on the computer:
$img = "deskfile:///D%3A%2FSCANS%2F%23AUKT%2Fimg2014%2F2014-06+SP%2FEPSON007.jpg"
how can i upload it the server without using the "file selector"?
If i enter the file adresses in the url window of a browser i can display the image.
But if i load the image in tag they won't display. I've read it's becuse of restrictions in the browser.
I can't add a value caluse to the either.
Is there anyway to upload the image from the string?
Or can i at least open the correct directory in the "file selector" so the user wont have the browse the whole computer when looking for the file?
Yes there is a way. You can use the File API with Html5 and/or a polyfill for this to load the image in the browser before posting it back to the server. The best such polyfill that I know of is called Moxy/Plupload. It includes Flash and Silverlight fallbacks for older browsers.
You can display the image because it is stored locally in your computer. How do you know where is the image going to be in the user's computer. The only way to access the user's file system is through the file selector, once the user has selected a file you can then use any API to save that file in the server on your terms, but you will not be able to see each of your users file system from you page (security reasons). Could you elaborate more in what you are trying to accomplish? What exactly are you trying to do?
I have hosted a Tomcat application on CloudBees which allows users to edit some XML and saves them. I need to download and save these files locally for my personal usage. However I could not find a way to do this. I tried the 'download source' option but it downloads the original files that I had uploaded and not the edited versions. However my application is able to access the edited versions (and so clearly everything is being saved all right). Getting these files back is extremely critical and necessary for me and is, in fact, the whole motive of this app. Kindly tell if there is some way to get back the files in CloudBees or any other free Java hosting site which would allow me to do it.
It's not very clear from your question how your app is currently dealing with these files, but I'll take a swing at providing some general info.
To support editing and downloading of files, your app design would need to address the following issues:
How do users edit/upload the changed XML?
Where does your app store the changed XML?
How does your app retrieve the edited XML and make it available for download?
For #1, you will need to provide an edit or upload interface in your app for manipulating the XML files. I'm assuming this is something your app has already solved using a form of some kind.
For #2, you need to pick an approach for storing the files that is appropriate for app's needs and the runtime environment where your app will be deployed. For instance, on CloudBees (or most other CLoud platforms), it's important to understand that the local filesystem of the app can be used for temporary storage, but it is not clustered and it will be wiped away each time the app is updated or restarted. If these XML files need to be available forever, you will need to store them in a persistent location that is external to the application's runtime instance. Most developers use databases (such as the CloudBees MySQL service) to store persistent data in this way. In general, your app can store these files anywhere, but your app needs to manage how to store them, and how to retrieve them later.
For #3, to allow a user to download the changed files, you will need to implement your own mechanism for retrieving the file from its persistent location, and then send it back to the user's browser. If you want something like right-click "Save As" to work, then your app will just need to support a URL that can display the edited XML file directly in the browser. If your app then provides a link to that URL, users can download it using RightClick+SaveAs. If you want the user to be able to click on a button/link and trigger a Save As dialog automatically, then you'd need to write a URL handler (Servlet) that serves the XML content up using a Content-Disposition header (see this StackOverflow article). This header will tell the browser that the file is supposed to be saved to disk, and allows you to provide a default file name.
I'm using valums file uploader and I want to display a file path in textbox after user choosen any file (like with standart file upload). Is there any possible solution to achieve this?
No. Based on my research I've found numerous posts suggesting that browser security features prevent objects from knowing the file system until the appropriate submit action is invoked.
Furthermore they suggest that if you do want to display the full path you'll need a non-browser solution like a java plugin (possibly even a flash object could do it).
I'm trying to find a way of finding out who is downloading what image from an image gallery. Users can download using a button beside the thumbnail or right click and use the "save link as" Is it possible to relate a user session or ID to a "save link as" action from all browsers using either PHP or JavaScript.
Yes, my preferred way of doing this would be via PHP. You'd have to set up a script which would load up the file and send it to the user browser. This script would also be able to log the download somewhere (e.g. your database).
For example - in very rough pseudo-code:
download.php
$file = $_GET['file'];
updateFileCount($file);
header('Content-Type: image/jpeg');
sendFile($file);
Then, you just have your download link point to download.php instead of the actual file. (Note that updateFileCount and sendFile are functions that you would have to provide, of course - this script is an example of a download script which you could use)
Note: I highly recommend avoiding the use of $_GET['file'] to get the whole filename - malicious users could use it to retrieve sensitive files from your web server. But the safe use of PHP downloads is a topic for another question.
You need a gateway script, like ImageDownload.php?picture=me.jpg, or something like that.
That page whould return the image bytes, as well as logging that the image is downloaded.
Because the images being saved are on their computer locally there would be no way to get that kind of information as they have already retrieved the image from your system. Even with javascript the best I know that you could do is to log each time a user presses the second mousebutton using some kind of ajax'y stuff.
I don't really like the idea, but if you wanted to log everytime someone downloaded an image you could host the images inside a flash or java app that made it a requirement to click a download image button. That way the only way for them to get the image without doing that would be to either capture packets as they came into their side or take a screenshot.
Your server access logs should already have the request for the non-thumbnailed version of the file, so you just need to modify the log format to include the sessionid, which I presume you can map back to a user.
I agree strongly with the suggestion put forward by Phill Sacre. For what you are looking for this is the way to go.
It also has the benefit of being potentially able to keep the tracked files out of the direct web path so that they can't be direct linked to.
I use this method in a client site where the images are paid content so must be restricted access.