Automatically list directory contents in client side Java Script? - javascript

I need to create an HTML page that will generate a list of hyperlinks to the contents of the client side directory in which it resides.
This would allow HTTP browsing of a local NAS, where no web server involved and contents can change dynamically.
This might be extremely useful to anyone serving content on a LAN. We need this feature in an educational setting, where directory contents will change frequently. Making manual links would be prohibitive, and file browser access is also needed.
Our Digital Media program will be much obliged to anyone who can help us with a solution.

Without any kind of server/back-end code, an in-browser NAS file explorer is not possible. Client-side JavaScript only interacts with the client. It's possible for client-side JavaScript to contact a server, however, and retrieve information about that server's directory structure, but, of course, that would require a server where you say you can't have one.

Related

Secure SCORM content in Offline player

I am developing Desktop Application (which launches a zip containing index.html in browser). I want to secure that zip from end user so that zip's content can not be accessed without App.
NOTE: zip will consist couple of HTML, JS and CSS files and my app will consume it by displaying it's index.html file in browser.
I can encrypt my content but before using/launching content's index.html (through my app in browser) I will have to decrypt and extract zip into local file system. At that time user will get access of decrypted content. Is there any way to somehow keep decrypted content in in-memory from where browser can access HTML file and display them?
The options you have:
one of in-memory filesystems: the simplest and the least useful that answer directly the question "a way to somehow keep decrypted content in in-memory from where browser can access HTML file and display them". If you are going to use a standard browser, the content should be accessible to it, so the user can read it as well.
local web server: no much better, if you keep using standard browser. You can use something like electron's webview or alternative embedded browsers in combination with client certification. This way you can ensure the content is being visible only in legitimate browser. It can be done with nodejs (+ desktop integration) and will protect the content from non-technical users. Anyone with a bit of coding skills will be able to reverse-engineer it tho.
custom web browser: a regular compiled desktop app. You will need to implement your own browser, and can decrypt the archive directly in the app's memory.

Possible download / upload manager embedded on html page with access to local filesystem

As the title indicates i want to have a certain application get access to the local file system. To describe why i will illustrate my situation:
I am a running a IIS WebApplication with the C# MVC 4 Framework as backend module. The site solely consists of HTML, CSS markup and some JS. The page will be loaded in IE11+ (Edge) only. For the standard procedure of displaying and accessing data from as well as sending data to the server this works quite fine.
On a certain page I want the user to be able to upload a file using a simple file dialog, like the one you can initiate with a simple <input type="file"> tag. I also want to offer the posibility to download files from the server but need to know where files has been saved / will be saved to.
As described on a lot of different websites, just like this one here, the HTML5 File API does a great job but will not be able to return the full qualified filename including the local path directions, same for JS accessing the file object.
As my research confirmed HTML5, JS and also SWF (Flash) will not report detailed information because they are all sandboxed applications or restricted by RFCs. I already unterstood and appreciate the effort to secure my trips to internet.
But in this case do need the paths where a file was upload from and the file has been downloaded to.
So my question is, what is the best way to expose the full path directions for a up- as well as downloaded file to report them back to the server?
Is it possible to embed a SWF object inside HTML which will run inside an Adobe AIR sandbox or is a signed JAVA Applet still the one and only solution to accomblish this security breaking task?
A solution i would also apreciate would be the possiblity to ask the user to get access the file system, like you grant access to the web push service to receive notifications.
Also if there is a possible solution which may suite my circumstances please let me know by adding some simeple examples / revealing some factful links, thanks in advance.

Read file names in a local folder in an HTML page

I am creating a HTML page where I need to display the names of the files present in the specific local folder, example - C:\Users\User1\Documents\folder1 . I tried to write the code in java script but have not succeeded yet. Most of the question threads mention about "ActiveXObject" to be used but that itself does not work for me.
Reference: JavaScript: Read files in folder
Can anyone help me in achieving this?
In general, you can't do that. Web pages do not have access to the local filesystem.
Chrome can access the contents of a directory that is selected using a file input field. However, other browsers, such as Internet Explorer and Firefox, have not implemented this feature at this time, nor is there currently any way to access a directory that was not selected by the user.
In theory, it is possible to read arbitrary files using a signed Java (not Javascript) applet. However, this requires the user to approve a series of extremely scary warning dialogs — and requires Java! — so it's really not a viable solution.
I'm afraid I may be the bearer of bad news for your design: The action you are requesting expressly violates the security model as specified in the File API spec. The client implementation of FileReader() must make sure that "all files that are being read by FileReader objects have first been selected by the user." (W3C File API , 13. Security Considerations: http://www.w3.org/TR/FileAPI/#security-discussion).
It would be a huge security risk of browser scripts could just arbitrarily open and read any file from a path without any user interaction. No browser manufacturer would allow unfettered access to the entire file system like that.
Thinking about it however, if it is all being run locally, you could use ajax to query a server side script that could return the directory you request.

how get list of files in a folder using javascript

I am working on project for desktop application. I am using Qt controls with visual c++.
I am loading an html file in the QWebView as,
m_pWebView->load(QUrl("../../../demo/index_Splash_Screen.html"));
Now, what i want is, say, I have some .zip files in my location "c:\demo", I want list (or array of file names) of the files present in that directory.
How can i do this through javascript ?
PS: I went through this link, but it didnt match my requirement. I have not worked with of html, javascript and jquery. Please help me.
I'm afraid you cannot access local files or directories using javascript due to security issues.
Edit: I hadn't thought about the file api so thought for a moment this might not be true, but without some user input to give permission, this still cannot be done.
This question has a good response from PhilNicholas:
I'm afraid I may be the bearer of bad news for your design: The action
you are requesting expressly violates the security model as specified
in the File API spec. The client implementation of FileReader() must
make sure that "all files that are being read by FileReader objects
have first been selected by the user." (W3C File API , 13. Security
Considerations: http://www.w3.org/TR/FileAPI/#security-discussion).
It would be a huge security risk of browser scripts could just
arbitrarily open and read any file from a path without any user
interaction. No browser manufacturer would allow unfettered access to
the entire file system like that.
Thinking about it however, if it is all being run locally, you could use ajax to query a server side script that could return the directory you request.
If it is a Windows application then you could access the local filesystem by using ActiveX objects. You might have a look at this link Reading a txt file from Javascript
Note that activeX usage is possible only when using IE as browser/engine; I used to need it a while ago for developing an HTML application (.hta files).

Javascript: Listing File and Folder Structure

As I have read, it is not easy for JavaScript to modify files on client PC. I am working on a web based file manager and would need to know the following:
Can JavaScript list files and folder structure on a client PC?
Can JavaScript list files and folder structure on a server?
If your answer is no, that Java Scipt can not list files and folders say on client's or server's C:\ drive, than would CGI script be the only solution?
Browser JS reading client PC's files: Depends
For a security reason, you can't access the files on the user's PC without the user's consent.
That's why the FileReader API is created around the file input box <input type="file"> and a drag-n-drop area since the whole idea is to "access the file with user's consent". Without the user intentionally putting the file for access, you can't access it at all.
Server-side JS reading own server's files: Yes
As for server, if you meant access the server using server-JS (NodeJS or Rhino), yes you can (How else would it serve webpages anyway?).
Browser JS reading own server's files: Depends
Accessing the server from the browser using JS works if you have an API to read files from it.
Browser JS reading other server's files: Yes, with a catch
To access other server's files without some API, you could resort to creating a web scraper or a web-spider that runs server-side (since browser can't cross domains due to the same origin policy) and have an API exposed to your browser.
However:
you can't crawl to all files as some may be restricted from outside access.
the public appearance of the structure could be different from the internal structure, especially if the site uses segmented url scheme
sites using query strings to generate pages cannot be crawled easily due to the number of permutations it could make, thus some pages might be unreacheable.
CGI won't be a solution either, as it only has access to the filesystem of your server, not that of the client visiting your site. The only way to access your client's filesystem from javascript seems to be the File API, which apparently is not implemented by many browsers.
It's a cludge but you could resort to a java applet or the dreaded active-x control.

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