I am attempting to make a webpage available offline.
I have added <html lang="en" manifest="cache.manifest"> to my page.
I have created cache.manifest with the following content:
CACHE MANIFEST
css/base.css
http://cdnjs.cloudflare.com/ajax/libs/jquery.selectboxit/3.8.0/jquery.selectBoxIt.css
http://ajax.googleapis.com/ajax/libs/jqueryui/1.11.4/themes/smoothness/jquery-ui.css
http://cdnjs.cloudflare.com/ajax/libs/entypo/2.0/entypo.woff
http://maxcdn.bootstrapcdn.com/font-awesome/4.2.0/css/font-awesome.min.css
css/affixed-sidebar.css
css/bootstrap.css
css/components.css
css/dodfont.css
css/helpers.css
http://ajax.googleapis.com/ajax/libs/jquery/1.11.2/jquery.min.js
http://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/js/bootstrap.min.js
http://www.parsecdn.com/js/parse-1.3.0.min.js
http://cdnjs.cloudflare.com/ajax/libs/toastr.js/2.1.1/toastr.min.js
http://ajax.googleapis.com/ajax/libs/jqueryui/1.11.4/jquery-ui.min.js
http://cdnjs.cloudflare.com/ajax/libs/moment.js/2.10.3/moment.min.js
http://gitcdn.github.io/bootstrap-toggle/2.2.0/js/bootstrap-toggle.min.js
http://cdnjs.cloudflare.com/ajax/libs/jquery.selectboxit/3.8.0/jquery.selectBoxIt.min.js
http://google-code-prettify.googlecode.com/svn/loader/run_prettify.js?lang=js&skin=sunburst
js/components.js
js/so-cat.js
http://maxcdn.bootstrapcdn.com/font-awesome/4.2.0/fonts/fontawesome-webfont.woff?v=4.2.0
fonts/glyphicons-halflings-regular.woff
http://maxcdn.bootstrapcdn.com/font-awesome/4.2.0/fonts/fontawesome-webfont.ttf?v=4.2.0
fonts/glyphicons-halflings-regular.ttf
http://fonts.googleapis.com/css?family=Raleway:400,200
http://code.ionicframework.com/ionicons/2.0.1/css/ionicons.min.css
fonts/glyphicons-halflings-regular.woff2
fonts/glyphicons-halflings-regular.woff2
fonts/glyphicons-halflings-regular.woff
fonts/glyphicons-halflings-regular.ttf
When I first visit the page in chrome, the browser will deliver the page and cache the page and all of the resources.
I expect that when I leave the page and come back, I will be served the live version of the page and I will only ever see the cached version if the server is not available.
Instead, on every visit after the first, I am served the cached version of the page. I can confirm I am seeing the cached version because, if I change the html file and refresh the webpage, I do not see the changes. If I clear or disable the cache and refresh, I see the changes as expected.
What do I need to do to ensure that, if the server is reachable, I am always served the live version of the page and all of its resources?
What do I need to do to ensure that, if the server is reachable, I am
always served the live version of the page and all of its resources?
Unfortunately, the simple answer here is: You can’t. For real. That is, at least not if you’re using a cache manifest. This a well-known serious design bug in the HTML5 appcache/offline-cache mechanism. It’s essentially broken by design.
And that's why using appcache is basically no longer recommended. It's just too broken.
And that's why the Offline Web applications section of the HTML Standard now says this:
This feature is in the process of being removed from the Web platform.
(This is a long process that takes many years.) Using any of the
offline Web application features at this time is highly discouraged.
Use service workers instead.
The only way to work around it and make clients quit using the cached contents is: completely remove your cache.manifest file from the server.
Do that and they’ll go back to fetching the current content.
The good news is that there’s a much better solution for offline Web applications in the works: Service Worker—more specifically, the Service Worker Cache and CacheStorage interfaces.
well ..
Solution 1 :
nowadays you can use ServiceWorkers but will only work over HTTPS .
Solution 2 :
you may add a hashed line and a version number to the manifest file like
# version 1.0.0
and change it every time you want to update the files in cache
Solution 3 :
you can use manifest in away that if online the browser will get the online data and if not you can write some js code to get some saved data .. maybe from indexedDB or localStorage
for more info read This Article
Related
In one of the online documents that talks about appcache for HTML5, it indicates that the cached files get updated once an offline user reconnects. I checked the original HTML5 appcache definition by W3, and I am not able to find anything that supports this statement.
Does anyone know if this is to be true?
Thanks in advance
MDN says the following, although if you scroll up on that page it says it's being deprecated.
If an application cache exists, the browser loads the document and its associated resources directly from the cache, without accessing the network. This speeds up the document load time.
The browser then checks to see if the cache manifest has been updated on the server.
If the cache manifest has been updated, the browser downloads a new version of the manifest and the resources listed in the manifest. This is done in the background and does not affect performance significantly.
And logic tells me that it would also depend on the app you're using, server you're trying to connect to and any special settings it might have, how long your browser keeps it's history, what it keeps, and if you saved the page to view offline - whether or not you have all the code/images saved in the right location(s).
Example:
Imagine you saved a page to view offline, and that page has a JS event handler that ran a while loop that did an ajax request every n seconds to do something, like make a number on a page change as long as you were online... As long as the loop is running, you suddenly connect to the internet, and it makes the request to the proper url with the right arguments, then it should go through, even though the url in your browser might say something like file:///C:/Users/you/Desktop/....
I've done this before, even though my url was like the one above. One time I was using braintree's drop-in javascript to a website, and using it's api on my backend. Trying to load the page when offline = Nothing. Online = Updated the spot on the page just fine when I had the required arguments, and it was pointing to the right url. If I got offline again, I could refresh the page, see the same images loaded in the <div>, but I couldn't send any data with it.
recently, I researched on HTML5 application cache. I plan to use it to cache the whole website, including html,js,css and image.
but I have one concern about using application cache.
if in the future, we have to change the architecture, we may drop the application cache. but according to the specification, if the browser fail to download manifest file for update check, it will use the cached version of the website. that means the user never get the new site?!
So my question is, is there any misunderstanding above?
and if not, is there any way for me to drop an application cache if the website already use it?
if the browser fail to download manifest file for update check, it will use the cached version of the website
That depends.
Case 1: If your browser can't connect to your webserver, it would probably use the application cache.
Case 2: If your browser can connect to your webserver, but the webserver returns HTTP status 404 or 410 for your manifest file, your application cache is marked as obsolete and will be removed completely by your browser. (see obsolete event in https://html.spec.whatwg.org/multipage/browsers.html#appcacheevents)
So the final answer is: to drop an application cache, return HTTP status code 404 or 410 for it's manifest file.
I am trying to make an xPages desktop application work offline, the challenge is how to make all the require resource available offline.
i have created the following manifest file and specified the same in pageManifest .
CACHE MANIFEST
#version: 0.0.15.7
jquery-1.10.2.min.js
angular.min.js
/DbPath/Angular.nsf/trashicon.gif
/DbPath/Angular.nsf/editicon.gif
/xsp/.ibmxspres/.mini/css/#Da&#Ib&2Tfxsp.css&2TfxspLTR.css&2TfxspSF.css.css
/xsp/.ibmxspres/dojoroot-1.6.1/dojo/dojo.js
/xsp/.ibmxspres/.mini/dojo/.en-us/#Iq.js
/DbPath/Angular.nsf/xsp/.ibmmodres/.css/bootstrap.min.css&custom.css
/DbPath/Angular.nsf/xsp/.ibmmodres/.js/jquery-1.10.2.min.js&bootstrap.min.js&angular.min.js&angularMisc.js
NETWORK:
/xsp/.ibmxspres/
/domjs/dojo-1.4.1/
/domjava/xsp/
I am not sure it is correct, it cache following image / Lib
/DBPath/Angular.nsf/trashicon.gif
/DBPath/Angular.nsf/editicon.gif
/xsp/.ibmxspres/dojoroot-1.6.1/dojo/dojo.js
/xsp/.ibmxspres/.mini/dojo/.en-us/#Iq.js
and the main page...
but it does not cache the
/DBPath/Angular.nsf/xsp/.ibmmodres/.js/jquery-1.10.2.min.js&bootstrap.min.js&angular.min.js&angularMisc.js
which is important, may b i am doing it wrong. Also how can we cache the oneui theme .
i am using Angular JS/JQuery which works fine when not cached, but it do not work with the manifest
if their is any simple example please share the link.
What part of the app do you want to make available offline?
If you're using full or partial updates, Server Side JavaScript and other server based stuff it cannot work offline.
Although this refers to Mobile apps it does have a sample showing you how to use HTML5 offline mode in XPages.
http://mobilecontrols.openntf.org
Offline.nsf contains basic HTML5 samples for how to do offline with XPages. MobileControlsOffline.nsf shows how to take a Dojo based mobile app offline.
The definition of a manifest makes an interesting read, as well as the URL document with the section about valid URLS.
As far as I know & is not a valid URL character if is isn't part of a parameter string that starts with ?.
So there are a set of actions you can try:
Switch off js/css combination. Since the files get cached locally anyway you don't benefit from it
Try (it might work) to replace & in the manifest with &
Let us know how it goes.
I did some tests (using Domino Designer) with Firefox and Chrome and it seems that everything can be cached in these browsers. My sugestion:
Instead of
/DBPath/Angular.nsf/xsp/.ibmmodres/.js/jquery-1.10.2.min.js&bootstrap.min.js&angular.min.js&angularMisc.js
Try a relative path without /
xsp/.ibmmodres/.js/jquery-1.10.2.min.js&bootstrap.min.js&angular.min.js&angularMisc.js
I used relative paths everytime. This is the cache manifest file used in my tests (all files were cached successfully):
CACHE MANIFEST
# 2013-01-07 v1.0.0
xsp/.ibmmodres/.js/js%2Fvendor%2Fmodernizr-2.6.2-respond-1.1.0.min.js&js%2Fvendor%2Fjquery-1.10.2.min.js&js%2Fvendor%2Fbootstrap.min.js&js%2Fvendor%2Fhandlebars.runtime-v1.1.2.js&js%2Fplugins.js&js%2Fmain.js
xsp/.ibmmodres/.css/css%2Fbootstrap.min.css&css%2Fbootstrap-theme.min.css&css%2Fmain.css
xsp/.ibmmodres/.js/jquery-1.10.2.min.map
/xsp/.ibmxspres/.mini/css/#Da&#Ib&2Tfxsp.css&2TfxspLTR.css&2TfxspSF.css.css
/xsp/.ibmxspres/dojoroot-1.6.1/dojo/dojo.js
/xsp/.ibmxspres/.mini/dojo/.es-es/#Iq.js
/xsp/.ibmxspres/.mini/dojo/.es/#Iq.js
NETWORK:
*
I have a special kiosk-solution with chrome where I need chrome to upon application start, load the start-url from cache, not try to fetch it online.
The reason is that this is, like I said, a kiosk-mode presentation, is is a screen standing in the public that reboots every night, and if the reboot happens while the ISP has downtime on the internet connection, chrome will only show an error page.
If I can get it to load the cached version of the page though, instead of trying to fetch it online, then the last valid version of the page will show, and through some nifty ajax-workings of mine ;) it will automatically update after a while. If THAT update fails, the currently displayed version of the page will remain until a subsequent update succeeds.
See my problem?
In a browser like firefox I could do it by starting the browser in off-line mode and after page load switch it to online-mode. Only FF doesn't work for me in the particulat project, and Chrome doesn't seem to have an off-line mode?
You could use HTML5 Offline Web Applications to accomplish that. It's probably very easy to set up in your case, just add a file like the following to your app's directory:
CACHE MANIFEST
index.html
help.html
style/default.css
images/logo.png
images/backgound.png
NETWORK:
server.cgi
This manifest should contain all the files you'll need to display some useful information and later grab current content via AJAX. There's also a NETWORK section, where you have to specify things that should not be cached (ie the script that delivers your Updates via AJAX).
You can load the manifest file by adding a manifest attribute to your tag (cache-manifest is the name of the file above):
<html manifest="cache-manifest">
Make sure your server delivers the cache manifest with a MIME-type of
text/cache-manifest MIME
Type or copy-paste the below flag setting into the chrome address bar.
chrome://flags/#enable-offline-mode
scroll down to enable offline stale mode.
Restart your browser.
If an offline version of the page is available in the system cache it will load up when you are not connected.
Gurus of SO
I am trying to play with CACHE MANIFEST/HTML5. My app is JS heavy and built on jquery/jquerymobile.
This is an excerpt of what my Manifest looks like
CACHE MANIFEST
FALLBACK:
/
NETWORK:
*
CACHE:
/css/style.css
/js/jquery.js
But somehow, the app doesn't load the files the first time itself and the entire app breaks down.
Is my format wrong?
Should I never load JS into the Cache?
How should I treat this differently to always check the network first if anything isn't available and only load stuff available from the Cache?
Thank you.
I tried a simple page with your cache manifest and it worked fine for me, so I'm not really sure what the problem is. But,
Yes, there is something wrong with the format. The entries in the FALLBACK section need to have two parts: a pattern, and a URL. This says "if any page matching the pattern is not available offline, display the URL instead (which will be cached)." The main example of this (as shown here) is "/ /offline.html", which means "for all pages, if we are offline and they are not cached, display /offline.html instead." However, I don't think this is the source of your problem since I tested it with your exact manifest and it still worked.
There is nothing special about JS files. It should be fine to load them into the cache.
I don't understand the third question. There are possibly two goals here: a) how do you check to see if there is a newer version of the file available online first, before going back to the cache, and b) how do you check the network to see if there is a file that is not cached, and if we are offline, fall back to an error page. The answer to (a) is that once you have turned on the cache manifest, things work very differently. It will never check for new versions of the files unless there is a new version of the manifest also. So you must always update the manifest whenever you change any files. The answer to (b) is the FALLBACK section.
See Dive Into HTML5's excellent chapter on this, particularly the section "The fine art of debugging, a.k.a. “Kill me! Kill me now!”" which explains how the manifest updates.
Also I don't think we've gotten to the meat of your question, because it's unclear what you mean by "the app doesn't load the files the first time itself". Which files don't load? Do they load properly after a refresh? Etc.
The only way I got this to work to refresh a cache was to rename the manifest file with a commit number or timestamp, and change the cache declaration to
<html manifest='mymanifest382330.manifest'>
I made this part of my build.