Updating Last-Modified for static content served with Wildfly - http-headers

I have a war with some static files (mostly images) in the webapp deployed on Wildfly. Sometimes the application needs to update some of those files, which then get replaced in the filesystem.
However Wildfly/Undertow seem to think that nothing has changed and the Last-Modified header in the response keeps showing the time before the update.
So I wonder what is Undertow using to determine the Last-Modified header shown. I've tried "touching" the parent directory, but to no effect.
In fact it looks like wildfly/undertow caches the last modified time after the first time it loaded a given resource.
Update
It's clearly a problem with the cache, since if I remove one of the files I requested before and request it again I get 500 Internal Server Error and stacktrace!

As pointed out in this thread the exploded war directory is not the right place for static resources that can be changed.
Instead one should use some other directory on the filesystem and configure the undertow subsystem to serve those pages. See for example this question.

Related

Issues with intern-runner and proxyUrl that contains subfolders

I need to setup intern to test ajax calls from a different server. I set everything up sort of following the official wiki in this address
https://github.com/theintern/intern/wiki/Using-Intern-to-unit-test-Ajax-calls
My config file has proxyUrl set to http://localhost:8080/sub
and http://localhost:8080/sub is setup as a reverse proxy to inter-runner in http://localhost:9000
When I run ./node_modules/.bin/intern-runner -config=tests/config from the tests root folder, the browser opens up and is able to request several files, until it tries to request the config file. That's when it receives a 404, because it requests the wrong address - http://localhost:8080/tests/config.js - without the sub folder.
I'm wondering if I'm missing something inside the config file, or if intern is not able to use proxies with subfolders. I tried to set the baseUrl parameter, but it had no effect.
Any ideas?
Update:
It seems that sometimes intern-runner uses the path provided in the config param, and sometimes it uses the one in the proxyUrl parameter inside the config file. As a workaround, what I did was to place the config file and the tests on 2 folders (actually I made a symbolic link). The first on tests/ and the second on sub/tests/ and ran it using ./node_modules/.bin/intern-runner -config=sub/tests/config.
It works, but it's kind of stupid and I really wished there was a better way to do it.
This is indeed a limitation/bug of intern. It assumes that the proxy sits at the root of the absolute domain name, i.e. that it has a pathname of /.
An issue has been created on intern's github repository here and the corresponding pull request that fixes the problem is here. Hopefully this gets merged into the upcoming 2.1 release of intern.

Force re-download of file cached with cache.appcache

My question is similar to this one, but the solutions provided haven't helped me: Force applicationCache to reload cached files
Here's the run down. I currently have a sencha touch application hosted on S3, and there's a problem which requires an update to the index.html file.
In order to enable offline access to the app, I've cached index.html in cache.appcache. Below is my cache.appcache file:
CACHE MANIFEST
# 127476e50461cf415c27fb33d81914faab1fc687
index.html
# 364c8e0f0cc7c9922d0019d083b4abba7d519e1c
resources/images/ajax-loader.gif
# 4028c1082f32387af25e2399aae7173ed0a51cf4
resources/images/cloud_download.png
# 40454710d633ca15b65d891d3842d3ef8b2136bf
resources/images/delete1.png
# 62c6a1ec578fa7d1d7a3117c2a84c5195c33ddb8
resources/images/loading.png
# ad85882c6285881966307da8da97ff597de9a486
resources/images/loadingbg.gif
# d2abb7549cd282c1e3fec6e9249d1e51ad5ec75d
resources/images/logo.png
FALLBACK:
NETWORK:
*
In hindsight, to enable offline access I should have probably left index.html as a non-cached network file with a fallback to some 'offline.html' file, but the app's been deployed for a while, and I need to make a change to index.html, and I just can't get the file to update, not even on my local machine by clearing the cache, and not by using private browsing as per the link above. I need to be able to change the file without the user having to do anything to receive the changes.
Here's what I've tried:
1) I removed index.html from the cache manifest and uploaded it. When I did that, and reloaded, the browser picked up the updated cache manifest and downloaded the files:
Application Cache Progress event (0 of 6) http://m.example.com/resources/images/loading.png (index):1
Application Cache Progress event (1 of 6) http://m.example.com/resources/images/ajax-loader.gif (index):1
Application Cache Progress event (2 of 6) http://m.example.com/resources/images/cloud_download.png (index):1
Application Cache Progress event (3 of 6) http://m.example.com/resources/images/loadingbg.gif (index):1
Application Cache Progress event (4 of 6) http://m.example.com/resources/images/delete1.png (index):1
Application Cache Progress event (5 of 6) http://m.example.com/resources/images/logo.png (index):1
Application Cache Progress event (6 of 6) http://m.example.com/ (index):1
Thankfully that means the browser isn't caching the manifest file, but unfortunately, even though it downloaded the index, the file didn't update. I've confirmed the file has been properly uploaded to the s3 bucket, and if I download the file the changes are there, but even after reloading the browser, clearing the browser cache multiple times, viewing the source shows the old index.html file. Note if I go to http://m.example.com/?bla, it works, so I know s3 is serving the correct file (although I haven't ruled out an s3 request cache), but http://m.example.com/ is still broken.
I'm guessing that, although the appcache is redownloading the file, at the browser level it's still cached, so appcache is just downloading the browser's cached version, although clearing the browser cache doesn't fix the issue.
2) I never set any expires headers on the file in s3 so not sure if s3 sets really long expiration headers by default, but I've tried adding Expires: -1 to index.html but doesn't help.
3) I've also tried uploading a new file called index2.html, and changing the index document in the s3 bucket to index2.html, but still I'm getting the old copy.
Not only do I need to get this working on my dev machine, but I also need to fix the issue on existing user's browsers, ideally without them having to do anything. I'm starting to think my only option is changing the app url, which I'd really rather not do. The index page seems so hard wired into the browser I'm not sure if even pointing m.example.com to a new ip address would help. Anyone have any ideas how I could solve this?
Update: I tried looking in the network tab in the chrome console while at the same time pushing up a new cache manifest and reloading the page. Unfortunately cache manifest requests don't seem to show in the network tab even if they're being re-downloaded.
Ok so after a bit more searching I discovered some idiosyncrasies in appcache, like the fact that whatever page includes your cache manifest, is auto cached by default regardless of your settings. I would have thought that, if the manifest was updated, the browser would at least re-download index.html, but it appears not. I used the solution found in the link below which indicates a workaround where you attach your manifest to another page which you reference in your source page via iframe, therefore allowing index.html to be not cached again.
My HTML5 Application Cache Manifest is caching everything
After doing that, to avoid future caching issues I made a duplicate page at 'offline.html' and made a failover pointing index.html to offline.html. So basically index.html is now never cached and isn't going to leave me stranded with an unusable domain, and when offline it will redirect to the offline page which can be happily cached for offline access. Phew!

HTML5 Cache Manifest problem

I am trying to use it to cache all the static files for my application (images, JS etc.) but I am running into a problem. My cache manifest file can looks like this:
CACHE MANIFEST
CACHE:
templates/v2/css/somecss.css
templates/v2/js/somejs.js
templates/v2/images/someimages.jpg
NETWORK:
*
This does cache those files that I have added to it (a few hundred so I omitted most of them out) but it also caches pages that I don't want (ex. index.php). It dramatically lowers the loadtime of the whole application but I need it not to cache any php files. I am using MultiViews if that makes any difference.
I have also tried adding a list of the files that I don't want cached under network but it still caches them. The full file can be found at https://app.emailsmsmarketing.com/cache.manifest
The problem might not be with the manifest itself.
Are you adding the manifest attribute to all your php pages? That could be the issue.
The manifest attribute should be included on every page of your web
application that you want cached. The browser does not cache a page if
it does not contain the manifest attribute (unless it is explicitly
listed in the manifest file itself. This means that any page the user
navigates to that include a manifest will be implicitly added to the
application cache.
http://www.html5rocks.com/en/tutorials/appcache/beginner/#toc-manifest-file-reference
You can also specify the .php files which you do not want to be cached in the NETWORK section. WHichever file you specify here will be accessed from the server.
You can make use of wildcard i believe for all php files

mod_rewrite to serve static cached files if they exist and if the source file hasn't changed

I am working on a project that processes images, saves the processed images in a cache, and outputs the processed image to the client. Lets say that the project is located in /project/, the cache is located in /project/cache/, and the source images are located wherever else on the server (like in /images/ or /otherproject/images/). I can set up the cache to mirror the path to the source image (e.g. if the source image is /images/image.jpg, the cache for that image could be /project/cache/images/image.jpg), and the requests to the project are roughly /project/path/to/image (e.g. /project/images/image.jpg).
I would like to serve the images from the cache, if they exist, as efficiently as possible. However, I also want to be able to check to see if the source image has changed since the cached image was created. Ideally, this would all be done with mod_rewrite so PHP wouldn't need to be used to do any of the work.
Is this possible? What would the mod_rewrite rules need to be for this to work?
Alternatively, it seems like it would be a fine compromise to have mod_rewrite serve the cached file most of the time but send 1 out of X requests to the PHP script for files that are cached. Is this possible?
You cannot acces the file modification timestamp from the RewriteRule, so there is no way around using PHP or another programming language for that task.
On the other hand this is really simple in PHP, so you should first check whether the PHP solution is good enough in you case. Only if it isn't you should look for alternatives.
What if you used the client to do some of the work? Say you display an image in the web browser and always use src="/cache/images/foobar.jpg" and add an onerror="this.src='/images/foobar.jpg'". In mod_rewrite, send anything that goes to the /images/ dir to a script that will return and generate an image in the cache.

HTTP caching headers settings weblogic

Does anyone know how to modify weblogic settings to set the HTTP cache header to a far future date?
For example in my current setup weblogic sets the http cache headers to expire in 5 hours (as a response of HTTP/1.1 304 Not Modified).
This is the cache header value on a .gif file ... Date: Tue, 16 Mar 2010 20:39:13 GMT.
I have re-checked and it's always 5 hours. There must be some for of settings that I can tweak to change it.
Thanks for your time!
You can use this property :
<wls:container-descriptor>
<wls:resource-reload-check-secs>-1</wls:resource-reload-check-secs>
</wls:container-descriptor>
The element is used to perform metadata caching for cached resources that are found in the resource path in the Web application scope. This parameter identifies how often WebLogic Server checks whether a resource has been modified and if so, it reloads it.
The value -1 means metadata is cached but never checked against the disk for changes. In a production environment, this value is recommended for better performance.
Static content is served by a weblogic.servlet.FileServlet that all web applications have by default but I couldn't find any way to configure HTTP headers. So either replace this servlet with your own servlet or use a Filter.
But the above comment is right, using a web server to serve static content is the "right" way to go: a web server does a better job at this and the application server has other things to do than serving static files.