I'm looking for a way to POST data to a backend script, use it to generate a temporary file on the fly (temporary in that it's dynamically generated and not saved to disk on the server), and then offer it to the client as a download.
I have the backend script functioning fine. The problem is that I haven't yet found a way to get the download prompt via an AJAX call.
If I weren't POSTing data, I would just use something like:
window.location.href = 'path/to/my/script.php';
Is what I'm after even possible? Can it be done without resorting to "hacks" like dynamically injecting a form into the DOM and submitting it, or opening up another browser window, etc.?
make POST request;
create the resource;
answer with the resource path;
window.location.href = resourcePath.
[optional] want to secure such resource from third part download? Attach a CSRF token, and make the resource available only if CSRF check is passed - otherwise congratulations, you just won a 403 puppy!
If the resource has proper headers, the browser will ask you to save / open it with specific app. / an so.
You can't do that without a classic form submit unless you can somehow make the download available via GET.
However, doing that would be a good idea anyway since download managers etc. often don't work well with POST - so simply make your script generate a temporary URL and then redirect to that URL using the JavaScript you already posted in your question.
Related
I'm building a web app (well at least one page on it) that shows the results of pings to different IPs.
I have no probs on Go displaying them on an HTML page. The simple thing I can't do (and I read so many tuto/threads that I'm lost and don't know what to do....) is to create a button "Refresh" that could just call back the "pingip" function i created in Go file.
Anyone has a concrete/"easy" example on how I could do this?
Assuming you have a HTTP Handler for your Go program, which is what is serving the page - then you can have the button simply do a window.reload() through JavaScript, which will reload the page in the browser and re-invoke the Go script.
If you want this to happen without a reload, then you'd have to create a different HTTP Route and use AJAX (look up the fetch method in JavaScript), get the results over the network (maybe as JSON) and then update the data in the frontend.
I am trying to pass a value using a link.
For example, if I want to add an email and password for a user to Sign In straight away in the RainLoop webmail.
I am trying using
http://demo.rainloop.net/?RainLoopEmail="new#email.com"&RainLoopPassword="12345"
or
http://demo.rainloop.net/?RainLoopEmail="new#email.com"&RainLoopPassword="12345"#ID
Is this possible to do?
It is possible but you will have to rewrite the rainloop PHP files by yourself. Also parsing passwords via the GET method is a very bad idea. Get commands will stay in your history so everyone who types in
demo.rainloop.net will see the ?RainLoopPassword="12345" also. It's not recommended, but possible. Another safer solution will be using the POST method. I suspect you will use this for you bookmarks or something? You can make an AJAX page which sends a POST request with the username and password to demo.rainloop.net. This way nobody will see your passwords and the effect is the same.
EDIT: For using an AJAX page you have to own a webserver, or register on a free hosting like http://freehostingnoads.net
I would like to write a plugin that calculates a cryptographic hash of every file rendered in the browser (images, html, css, etc), without causing a second get request for the various files. Ideally I could listen for each resource being loaded and get a copy of the bytestream that comes back.
Does anyone know if such a hook exists / what it would be called?
Thanks!
Not at the moment.
There is a feature request to allow (at least) read access to response body in chrome.webRequest.onCompleted, but it's not currently implemented.
Well, using HTML5 file handlining api we can read files with the collaboration of inpty type file. What about ready files with pat like
/images/myimage.png
etc??
Any kind of help is appreciated
Yes, if it is chrome! Play with the filesytem you will be able to do that.
The simple answer is; no. When your HTML/CSS/images/JavaScript is downloaded to the client's end you are breaking loose of the server.
Simplistic Flowchart
User requests URL in Browser (for example; www.mydomain.com/index.html)
Server reads and fetches the required file (www.mydomain.com/index.html)
index.html and it's linked resources will be downloaded to the user's browser
The user's Browser will render the HTML page
The user's Browser will only fetch the files that came with the request (images/someimages.png and stuff like scripts/jquery.js)
Explanation
The problem you are facing here is that when HTML is being rendered locally it has no link with the server anymore, thus requesting what /images/ contains file-wise is not logically comparable as it resides on the server.
Work-around
What you can do, but this will neglect the reason of the question, is to make a server-side script in JSP/PHP/ASP/etc. This script will then traverse through the directory you want. In PHP you can do this by using opendir() (http://php.net/opendir).
With a XHR/AJAX call you could request the PHP page to return the directory listing. Easiest way to do this is by using jQuery's $.post() function in combination with JSON.
Caution!
You need to keep in mind that if you use the work-around you will store a link to be visible for everyone to see what's in your online directory you request (for example http://www.mydomain.com/my_image_dirlist.php would then return a stringified list of everything (or less based on certain rules in the server-side script) inside http://www.mydomain.com/images/.
Notes
http://www.html5rocks.com/en/tutorials/file/filesystem/ (seems to work only in Chrome, but would still not be exactly what you want)
If you don't need all files from a folder, but only those files that have been downloaded to your browser's cache in the URL request; you could try to search online for accessing browser cache (downloaded files) of the currently loaded page. Or make something like a DOM-walker and CSS reader (regex?) to see where all file-relations are.
I'm currently using CyberNeko in an attempt to grab information I want from a website. However, I believe the website checks the user agent/browser version to keep from just grabbing the url content.
I am aware of using htmlunit to change the browser version, but not sure if I can go about this using CyberNeko.
Does anyone know if it's possible to do such a thing?
I've never used CyberNeko, but I thought it was just a HTML parser, i.e. I didn't think you could use it to issue the HTTP requests and actually download the web page.
It could be the fact that the HTTP request issued by CyberNeko is missing various headers such as the user agent header. An easy way to ensure that the HTTP request looks like a request sent from a browser is to use HttpClient instead of CyberNeko to download the web page. There's some example code available here.
Once you've successfully downloaded the page, use CyberNeko to parse out the bits you're interested in.