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 There are possibly two goals here: a) how do you check to see if there is a newer version of the file available online first, before going back to the cache, and b) how do you check the network to see if there is a file that is not cached, and if we are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.
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.
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
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 am testing HTML5's offline capabilities, and the cache seems to be a bit overactive. My cache.appcache file is as follows:
CACHE MANIFEST
CACHE:
#v1.4
js/js.js
NETWORK:
network2.html
FALLBACK:
/ offline.html
Basically I want to only display network2.html when the web is available - otherwise it should fall back to offline.html.
However, if I have accessed network2.html with the web connection live it keeps displaying it when there is no connection - surely it should fall back to offline.html? I thought only pages referenced in the CACHE section should be cached in the first place anyway?
I have tried in multiple browsers, clearing the browser data, refreshing multiple times etc.
Sorted it - it turns out that any file whose html tag references the manifest will be cached itself, whether or not that file is mentioned in the CACHE section. This even overrides if it is referenced in the NETWORK section.
Thanks to robertc on this answer which gave me the tip.
In short, you only need to have one reference to the manifest, usually in your 'default' view, not all files that may be referenced by the manifest itself. Not very clear in the HTML5 docs.
Every URL can be linked to a single cache manifest. But I want several cache manifests linked to a same URL. Here is the reason:
Some files I want to be cached are rarely updated and large.
So everytime the cache gets updated these large files get re-downloaded even though they may not have been changed.
So I want to split up the cache. One cache for theses rarely updated large files and another cache for the often updated light files.
Do you guys have any idea how to split up an HTML5 cache?
The most efficient way is:
a) Use far-future expiration date (max-age) on all resources mentioned in manifest's CACHE section and add timestamp suffix to each file in the CACHE section, e.g.:
CACHE:
menu_1355817388000.js
toolbar_1355817389100.js
b) When any of the above files change on the server, regen/update manifest to change the timestamp. Only the file with the modified timestamp will get downloaded next time. Mission accomplished.
Note: Reload the page twice in the browser, as on the first refresh browser downloads just the manifest and uses old cached resources to paint the page. This is done to speed up displaying the page (there are tricks to handle this issue of double refresh, but they are outside the scope of your question)
See more info in this long but best article I ever seen on appcache.
Use an iframe
Your page's cache manifest would include the light files and the cache manifest of an iframe loaded by this page would include the large files
On chrome the iframe's application cache will also be used for the page. I didn't tested this method on other browsers yet.
see a live example at http://www.timer-tab.com and if you are using chrome see its split up cache at chrome://appcache-internals/
When the manifest file is changed and the files of the application cache are downloaded again, the normal HTTP caching rules still apply. This means that if you set the correct HTTP caching headers for these large files, you'll get a 304 so these files are not downloaded again. So it's not necessary to split the application cache.
Maybe an answer but I'd more like to shed some light on my findings as a I troubleshoot my own webapp.
I've discovered that I can use 2 iframes (manifest_framework) and (manifest_media) to load the manifests, but i'm still not exactly clear how they are targetted, but I had limited success.
manifest_framework:
CACHE MANIFEST
CACHE:
appdata.ini
dialog.png
jquery.min.js
login.htm
login.js
manifest.appcache.js
NETWORK:
*
FALLBACK:
manifest_media:
CACHE MANIFEST
CACHE:
manifest_fwk.php
od/audio_track_1_1.m4a
od/audio_track_1_2.m4a
od/audio_track_1_3.m4a
od/audio_track_1_4.m4a
od/video_1.mp4
od/video_2.mp4
od/video_3.mp4
NETWORK:
*
FALLBACK:
./ webapp.php
./index.php is the page the 'landing page' which itself isn't cached but falls back to webapp.php when offline.
What I don't understand is how these link to the webapp.php page.
I am finding I can only get access to one or the other manifests cache.
The above works in mobile safari, the media would be cached, and image but not necessarily the JS or images in the framework manifest.
Anyone have more examples where multiple manifests are referenced from the one URL/page?
The W3C working group has abandoned the file system api, so it SHOULD NOT BE USED anymore.
We'll likely see it fall off the next version of Chrome.
http://www.w3.org/TR/file-system-api/
CACHE MANIFEST
# This is a comment.
# Cache manifest version 0.0.1
# If you change the version number in this comment,
# the cache manifest is no longer byte-for-byte
# identical.
demoimages/mypic.jpg
demoimages/yourpic.jpg
demoimages/ourpic.jpg
sr/scroll.js
NETWORK:
# All URLs that start with the following lines
# are whitelisted.
# whitelisted items are needed to help the site function, you could put regularly
# changing items here
http://example.com/examplepath/
http://www.example.org/otherexamplepath/
CACHE:
# Additional items to cache.
demoimages/allpics.jpg
FALLBACK:
demoimages/currentImg.jpg images/stockImage.jpg`
If the Iframe trick does not work, use the HTML5 FileSystem API
See http://updates.html5rocks.com/2012/04/Taking-an-Entire-Page-Offline-using-the-HTML5-FileSystem-API