I am using Wildfly 9.0.2.Final, while in development, all my files that uploaded via my web service and stored in resources/images are gone when I perform a full-publish (luckily this are development dummy images). In production, where is the best place to store or best practice to prevent files/images from missing?
If the files belong somehow to your application, place the somewhere inside the web application (and outside of WEB-INF). They will be accessible through the respective URL path.
If your application needs to store user data that gets uploaded dynamically during application runtime and shall persist even if you redeploy the application, then you better have a configurable directory on disk. One default option to find the JBoss/Wildfly data directory could be to query for the system property 'jboss.server.data.dir'.
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I have a website in which users would upload various and later access them.
The files are stored in a specific path in the server at this point. Now if I need to have multiple servers for the website, what is the best way to make the user uploaded files accessible across multiple servers. Amazon s3 is one option that has crossed my mind. What other options do I have?
First, you can try using a CDN (http://en.wikipedia.org/wiki/Content_delivery_network).
Also, you can make it in house, by having specialized servers setup for static content. You will need maybe a lookup server, to know for each file on what server can be found. It will also contain the logic to determine what is the best server to use to save the file. This is more complicated, as you will have to make the load balancing and take care of geographic location of users.
I have a webapp using the Scala-based Scalatra web framework. The problem is, anytime the application is re-deployed, or anytime the app-server is rebooted, all session data is lost. This means (to name one downside) users must re-login every time we make an update to the site.
Some research reveals there are, apparently, "container-specific" ways to make sessions persist across app and server reboots (e.g., in the case of Tomcat), but this has two shortcomings:
If the app is not always deployed in the same container (and in the case of Scalatra, an embedded Jetty is used for dev purposes) then I'll need separate configuration for each container.
Using a server-local configuration file is much more fickle -- it's likely to get lost in server migrations, and it won't be automatically available to each instance (e.g., to each developer) of the app, whereas something stored with the core application code is much easier to test, retain, and generally keep track of.
So, to sum up...
Is there a generic, container-neutral way to make sessions persistent? Even if only by overriding appropriate methods in the Java/Servlet stack and storing the session data manually?
Barring that, is there a way to store relevant configuration for multiple containers (e.g., for both Jetty and Tomcat) in my application code (web.xml or similar)?
Thanks -- any insights appreciated!
I have an application in the store that has a bunch of UITableViews, each has a bunch of items that when selected, load a UIWebView that loads a local HTML file. The reason I do this is so it allows for viewing when there is no internet access, however it makes it tedious to update.
How would I go about both keeping local files, and keeping web files, so that If I update one on the web it would let the user know there is an 'update' and it can download and overwrite the old file with the new. Is this possible? Like I would make myself a backend to edit my HTML, and have a connection to the app so whenever I clicked save the app would know to ask the user to update the files so I don't have to submit to apple for such small updates.
But I still need to allow offline viewing in case they didn't have internet access.
What technologies or techniques would I have to research to accomplish this?
Thanks
what you're looking for is an html5 concept called application cache.. it directly addresses your problem. With app cache you can cache static content at the client side, which they can view even if they're offline, yet they can update it when the content on the server changes. If you look around you'll see people use this for the iPhone as well.
update:
What way would I go about rewriting files on the phone from ones on a server?
you basically update the cache to do that. from the docs:
The application cache automatically updates only if the manifest file
changes. It does not automatically update if resources listed in the
manifest file change. The manifest file is considered unchanged if it
is byte-for-byte the same; therefore, changing the modification date
of a manifest file also does not trigger an update. If this is not
sufficient for your application, you can update the application cache
explicitly using JavaScript.
I encourage you to do some reading on html5 local storage just to get the concept of local cache and manifest files etc, then just follow through the instructions on the apple docs.. It's not that difficult.
You can cache the content as abbood said but that won't allow you to provide initial offline content.
Another approach would be to use NSURLProtocol, which allows you to swizzle a request. For example, if you have a request for "http://google.com", you would be able to either change the URL or load your own content (say from a local directory).
I'm in the process of building a simple update server for an application. The parts of the application being updated are configuration files; the most up-to-date copies of these files exist on the update server and these files can be edited by the individual managing the application (the "application manager") at any time. However, I don't want the application to be able to download one of these files while the file is being edited by the application manager; this would obviously cause consistency issues. How can I prevent these files from being accessed in an inconsistent state? Alternatively, would a solution be to provide a checksum along with the file that the application could use to determine if the file was received in a consistent state?
EDIT: I've seen this post concerning access restrictions using .htcaccess and think it could be of use. However, I want the application manager to do as little thinking as possible; having them forget to re-allow connections might be problematic. That being said, they're going to have to do some work at some point; maybe this is the way I should go?
I am developing an iPhone app which retrieves information via NSUrlRequest and displays through UIWebView.
I want to hold initial data (such as HTML pages, images) as a cache so that users of my app can access to data without network costs at the first time.
Then, if data on my web server are updated, I would download them and update the cache.
For performance issues, I think it is better to store data on file system than on core data.
Yet, I think it's not possible to release a new app writing data on disk.
So, I am about to store initial data(or initial cache) at Core Data, and when users launch my app for the first time, I would copy the data to disk (like /Library folder).
Is it, do you think, a good approach?
Or,...hmm, can I access to Core Data using NSUrlRequest?
One more question,
I might access to file system using NSURL, which is the same as to data on the Web. (right?)
My app would compare version of the cache with version of data on my web server, and if it's old, retrieve new data.
and my app will access only to file system.
All data are actually HTML pages including script, and images. And, I want to cache them.
could you suggest a better design?
Thank you.
Is it, do you think, a good approach? Or,...hmm, can I access to Core Data using NSUrlRequest?
No.
One more question, I might access to file system using NSURL, which is the same as to data on the Web. (right?) My app would compare version of the cache with version of data on my web server, and if it's old, retrieve new data. and my app will access only to file system. All data are actually HTML pages including script, and images. And, I want to cache them.
Yes.
But you could also be more clever. And by "more clever" I mean "Matt Gallagher." Take a look at his very interesting approach in Substituting local data for remote UIWebView requests.