Is it possible to download html files and images from a server and store them in the same disk location as the html file doing the downloading?
I need to do this because I have an app that is a database of HTML files and these files change from time to time. When updates occur, it would be good if the HTML5 app prompted the user to do an update and if accepted, the file were downloaded and replaced the old file set.
The app has to work offline, hence the need to download the data.
In most browsers, yes. Read about the cache manifest http://diveintohtml5.ep.io/offline.html
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I have a React app where I need to upload files (pdf files for example), and store them under distinctive folders,
What I need to know, is if there is a way to download or get download link for an entire folder X,
I tried with firebase, but it only offers to get link of a single file at a time, not full folder, does S3, or something else have this option?
Thanks.
I'm trying to retrieve a picture from my file system after a good storage,(instead of putting it in the database I copy it to the disc and i put the path to the db)
I had store the picture to c:\images\ folder and supposing that the name the complete path is c:\images\mypic.jpg
when I try to retrieve it a set the img src attribute to <img src="c:\images\mypic.jps"> by using some java code
in the browser console I found this error Not allowed to load local resource: file:///C://images//mypic.jpg
Question: how to fix these path problem ? where Should I store the pictures ? and from where should I retrieve them ?
sending tag <img src="c:\images\mypic.jpg"> would cause user browser to access image from his filesystem.
if you have to store images in folder located in c:\images i would suggest to create an servlet like images.jsp, that as a parameter takes name of a file, then sets servlet response content to an image/jpg and then loads bytes of image from server location and put it to a response.
But what you use to create your application? is it pure servlet? Spring? JSF?
Here you can find some info about, how to do it.
In Chrome, you are supposed to be able to allow this capability with a runtime flag --allow-file-access-from-files
However, it looks like there is a problem with current versions of Chrome (37, 38) where this doesn't work unless you also pass the runtime flag --disable-web-security
That's an unacceptable solution, except perhaps as a short-term workaround, but it has been identified as an issue:
https://code.google.com/p/chromium/issues/detail?id=379206
You have Two alternatives :
First one is to create a ServletImageLoader that would take as a parameter an identifier of your image (the path of the image or a hash) that you will use inside the Servlet to handle your image, and it will print to the response stream the loaded image from the server.
Second one is to create a folder inside your application's ROOT folder and just save the relative path to your images.
Many browsers have changed their security policies to no longer allow reading data directly from file shares or even local resources. You need to either place the files somewhere that your tomcat instance can serve them up and put a "regular" http url in the html you generate. This can be accomplished by either providing a servlet which reads and provides the file putting the file into a directory where tomcat will serve it up as "static" content.
The concept of http location and disk location is different. What you need to do is:
for uploaded file summer.jpg
move that under a known (to the application) location to disk, e.g c:\images\summer.jpg
insert into db record representing the image with text summer.jpg
to display it use plain <img src="images/summer.jpg" />
you need something (e.g apache) that will serve c:\images\ under your application's /images. If you cannot do this then in step #2 you need to save somewhere under your web root, e.g c:\my-applications\demo-app\build\images
This error means you can not directly load data from file system because there are security issues behind this. The only solution that I know is create a web service to serve load files.
Here is a simple expressjs solution if you just want to run this app locally and security is not a concern:
On your server.js or app.js file, add the following:
app.use('/local-files', express.static('/'));
That will serve your ENTIRE root directory under /local-files. Needless to say this is a really bad idea if you're planning to deploy this app anywhere other than your local machine.
Now, you can simply do:
<img src="/local-files/images/mypic.jps"/>
note: I'm running macOS. If you're using Windows you may have to search and remove 'C:\' from the path string
Do not use ABSOLUTE PATH to refer to the name of the image for example: C:/xamp/www/Archivos/images/templatemo_image_02_opt_20160401-1244.jpg. You must use the reference to its location within webserver. For example using ../../Archivos/images/templatemo_image_02_opt_20160401-1244.jpg depending on where your process is running.
I want to retrieve some HTML content from the web (for example RSS feed), save it for offline use and then display it in a Web Browser control in a Windows Phone application. I can easily save the content as a string and use NavigateToString() method to display the HTML but what do I do with the images? I can download them and save them and even replace the src attribute of the img tags but how do I intercept the image loading in the web browser control and feed it images from the local database?
Well you will have problem with any asset, not only images (unless you're talking about HTML without any external javascript or CSS). You could possibly have a method to detect asset sources (<script src=""> or <img src=""> or <link href=""> are some obvious examples). Then you would download that asset as a local file. Then when you're displaying it, you would replace all assets in your HTML string with local copies instead.
I haven't worked on Windows Phone at all but I think your solution would be around these lines.
I ended parsing the HTML downloading the images and replacing the src attribute with the local file name. Then I saved the html in the local storage so that relative links continue to work. Sadly I did not find a way to store the content in the database because if I used NavigateToString to provide the HTML I cannot provide the image data.
If my asp.net website has some silverlight content(XAP file, silverlight video content), does user have to download all content everytime he open my website in browser, or date stay saved/cached on Hard Drive even if user turn of computer? In what folder data is saved and how long does it stay saved? I read somewhere about "Reduce XAP size by using application library caching" option when creating silverlight project. Is that option enabled by default(Don't have Silverlight installed in VS)?
I recommend on reading up on Silverlight and XAP caching here. In short, yes, the Silverlight XAP is cached and only re-loaded when the XAP has been modified or your browser's cache has been cleared.
The browser will cache resources, libraries, xaml, and binaries needed to run the application. This is handled by the browser cache and your files are stored in the temporary internet files directory.
Assembly caching allows your assemblies to be cached by the browser separately from your XAP file. The benefit of this is that you can update your XAP and the browser not have to re-download your assemblies, just the updated XAP file. This can make a big difference in downloads speeds when users re-visit your site.
Sometimes, caching a XAP file can work against you as publishing an update doesn't necessarily dirty the cache. IE handles updates better than Chrome and Firefox. The link above shows you how to configure IIS to immediately expire the web content on publish. This CodeProject link also has a good method for updating the ASP.NET page content with a dynamic string to force a cache refresh on publish.
I am writing a program in C that acts like a proxy server in a Linux system: Client asks it for a web page,
it sends an HTTP GET Request to a distant server, and it gets the servers response (web page), which is saved in an .html file.
Here goes my problem: Most web sites got some references to images, so when i try to view the .html file proxy created, the images don't appear.
I have searched a lot, but found nothing..Is there a way to write some code to GET images too?
Thank you in advance
You're going to have to write code that parses the HTML file you get back and looks for image references (img tags), then queries the server for those image files. This is what web browsers are doing under the hood.
You have an additional problem though which is that the image references in the HTML file are to the original server. I'm assuming that since they don't load for you the server that returned the original HTML isn't available. In that case after you get each image file you will need to give it a name on the local filesystem and then alter the reference in the HTML (programmatically) to point to your new local image name.
So for example:
<img src='http://example.com/image1.png'>
would become
<img src='localImage1.png'>
If you're querying arbitrary websites then you'll also find that there are various other files you'll need to do the same with like CSS files and JavaScript files. In general its hard to mirror arbitrary web pages accurately - browsers have complex object models they use to interpret web pages because they have to deal with things like CSS and Javascript and you may need to be able to 'run' all that dynamic code to even be sure what files to download from the server (e.g. JavaScript including other JavaScript etc).