I'm trying to write an HTML5 offline application but can't seem to get Chrome to accept the cache manifest file.
Chrome logs the following output to its console while loading the application:
Creating Application Cache with manifest http://localhost/cache.manifest
Application Cache Checking event
Application Cache Error event: Manifest fetch failed (-1) http://localhost/cache.manifest
However, if I remove all lines from the manifest file except for the first line (i.e. "CACHE MANIFEST") Chrome accepts the manifest:
Creating Application Cache with manifest http://localhost/cache.manifest
Application Cache Checking event
Application Cache Downloading event
Application Cache Progress event (0 of 0)
Application Cache Cached event
But, as soon as I add a new line to the manifest (even if that next line is empty) Chrome reverts to complaining that the fetch failed.
All files are being served locally from a Windows 7 PC via Python using SimpleHTTPServer on port 80. I've updated the types_map in %PYTHON%/Lib/mimetypes.py with the following line:
'.manifest': 'text/cache-manifest',
The manifest should contain the following:
CACHE MANIFEST
scripts/africa.js
scripts/main.js
scripts/offline.js
scripts/libs/raphael-min.js
favicon.ico
apple-touch-icon.png
To cache a website offline (HTML5) you need to specify all the files needed for it to run. In short specify the site main components needed.
Easy way to create a manifest is in Note Pad.
Note: CACHE MANIFEST needs to be first line and your files will follow after a line space as follows:
CACHE MANIFEST
Scripts/script.js
Content/Site.css
Scripts/jquery-ui-1.8.20.min.js
Scripts/modernizr-2.5.3.js
SESOL.png
Scripts/jquery.formatCurrency-1.4.0.min.js
http://code.jquery.com/mobile/1.2.0/jquery.mobile-1.2.0.min.css
http://code.jquery.com/jquery-1.8.2.min.js
http://code.jquery.com/mobile/1.2.0/jquery.mobile-1.2.0.min.js
Content/themes/images/icons-18-white.png
Controllers/AccountController
Controllers/HomeController
Models/AccountModels
Account/Login
Home/CheckOut
Note2: remove all spaces after each line.
Note:3 you need to follow the exact format FOLDER/File or FOLDER/FOLDER/FILE ect....
Just because you have a manifest file doesnt mean it will load. you need to add the following to the Tag:
<html manifest="~/cache.manifest" type="text/cache-manifest">
Don't forget that after you add this it's cached the first time the page loads. So you need to register a cache event in the 'mobileinit' event.
$(document).on("mobileinit", function () {
//register event to cache site for offline use
cache = window.applicationCache;
cache.addEventListener('updateready', cacheUpdatereadyListener, false);
cache.addEventListener('error', cacheErrorListener, false);
function cacheUpdatereadyListener (){
window.applicationCache.update();
window.applicationCache.swapCache();
}
function cacheErrorListener() {
alert('site not availble offline')
}
}
Download Safari and use the web inspector to find errors.
http://developer.apple.com/library/safari/#documentation/appleapplications/Conceptual/Safari_Developer_Guide/1Introduction/Introduction.html#//apple_ref/doc/uid/TP40007874-CH1-SW1
Tip: Chrome's developer tools "F12" will show you the errors in the manifest load. ie the files you still need to add.
Hope this helps, covers the entire process. I assuming if you are at this stage in development you new to add these to the mobile init:
$.mobile.allowCrossDomainPages = true; // cross domain page loading
$.mobile.phonegapNavigationEnabled = true; //Android enabled mobile
$.mobile.page.prototype.options.domCache = true; //page caching prefech rendering
$.support.touchOverflow = true; //Android enhanced scrolling
$.mobile.touchOverflowEnabled = true; // enhanced scrolling transition availible in iOS 5
Safari Developer Guide:
https://developer.apple.com/library/safari/#documentation/AppleApplications/Reference/SafariWebContent/Client-SideStorage/Client-SideStorage.html#//apple_ref/doc/uid/TP40002051-CH4-SW4
Have you tried anything like https://manifest-validator.appspot.com/ to validate your manifest?
I've struggled with my manifest file for quite a while, it is really hard to pinpoint what is wrong. Could be something as simple as wrong encoding to an extra line break at the start.
Today I experienced exactly the same problem. After hours of working I came the the key point: the format of manifest file. In short, the file must begin a new line ONLY with ascii(0A), not ascii(0D), or ascii(0D + 0A). Only in this way can I live with Chrome, or I will get a blank page, and the error info in the console window.
According to w3c, (http://www.w3.org/TR/html5/offline.html), in “5.6.3.2 Writing cache manifests”，both 0A, 0D and 0D + 0A are all acceptable. So, my opinion is: Chrome is not compatible with w3c in the point.
Further more, say, if myapp.js is to be cached, it MUST follow the same rule: begins a new line only with ascii(0A), or Chrome will throw the same info in the console windows.
My Chrome is 13.0.782.107
I have now resolved this issue by switching to CherryPy for serving these files :)
If anyone else becomes similarly stuck but wants to keep the server part simple, the following Python may be sufficient for getting started:
import cherrypy
class SimpleStaticServer:
#cherrypy.expose
def index(self):
return '<html><body>Go to the static index page</body></html>'
cherrypy.config.update({
# global
'server.socket_host': '192.168.0.3',
'server.socket_port': 80,
# /static
'tools.staticdir.on': True,
'tools.staticdir.dir': "(directory where static files are stored)",
})
cherrypy.quickstart(SimpleStaticServer())
If you want to visit the "site" from another device, you'll need to use the external IP address (for me this was 192.168.0.3). Otherwise, you can just use '127.0.0.1' for the 'server.socket_host' value. I then point my browser to http://192.168.0.3/index.html to get my static index page.
I have resolved this issue in visual studio for MVC application.
follow below steps:
I have created .appcache file in notepad and copy manifest file content into it.
(you don't need to create .Manifest file OR not create Manifest.cshtml view. just create .appcache file in notepad.)
give reference as
<html manifest="~/example.appcache"> in view
and issue will be resolved
I think the line
CACHE:
is missing in the manifest file (should be the 2nd line, before the list of files.
Related
so ive got a file-server thats listening on my IP.
I created a test.html, test.js and a manifest.appcache.
My appcache says :
CACHE MANIFEST
CACHE:
test.html
test.js
NETWORK :
*
Meanwhile, my test.html :
<html manifest="manifest.appcache">
If i access on the test.html, everything is working, however if i want to change something in my html file and reload the page, nothing changed(the old html file is cached).
If i change something on my appcache file, for example just edit a space behind the variables and reload my page, it accepts all changes from my html file and is not ignoring the changes anymore.
Why is that?
How can i make it listen to my html file everytime i reload the page?
This is how the cache works. If you want to refresh the cache as you already said you need to change your manifest file.
You must modify the manifest file itself to inform the browser to refresh cached files.
But you can use JS to check if the cache is changed.
You can get the cache object like this: window.applicationCache
window.addEventListener('load', function(e) {
// Add an event listener to the cache
window.applicationCache
.addEventListener('updateready', function(e) {
// Check if ready to update (The update ready status is 4)
if (
window.applicationCache.status ==
window.applicationCache.UPDATEREADY) {
// Get new app chache
// window.location.reload();
window.applicationCache.swapCache()
}
}, false);
}, false);
Check the official docs here: https://html.spec.whatwg.org/#applicationcache
Please note this feature is deprecated an you shouldn't use it
From MDN:
This feature has been removed from the Web standards. Though some browsers may still support it, it is in the process of being dropped. Avoid using it and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.
What should I do?
You should be using the new Service Worker API, it is a direct replacement for the Application cache. Service workers have all the features off App Cache and even more.
For Service Worker API check these:
MDN
Google Dev
W3C (Github)
I have been trying to figure out HTML5's new AppCache, but I feel extremely limited here.
Let's assume that I have a website with four pages:
index.html
about.html
portfolio.html
contact.html
I have the above resources outlined in the manifiest, along with all of the website's resources. The manifest looks like the below:
CACHE MANIFEST
# 2013-05-23 2:33 PM
# Master Manifest
index.html
about.html
portfolio.html
contact.html
styles/reset.css
styles/styles.css
NETWORK:
*
I have added the appcache file type to the server configuration and have used the correct HTML tag attribute on each page listed above. Just for the record, the element looks like so:
<html lang="en" manifest="example.appcache">
I have tested this setup out on my mobile device, and everything works perfectly fine... Unless I don't load every page. It seems that I have to go to each page and cache it via my mobile browser, after which I may turn off DATA and go offline for my device to be able to browse the APPCACHE'd website.
But, here's my question - How do I setup AppCache to allow me to go to index.html, cache that page, and cache the rest of the resources in the manifest? Without having to visit and manually cache each resource?
If you cannot, then I would have to ask; doesn't that sort of defeat the idea behind AppCache and Offline Accessibility?
Thank you so much for the help all! :)
You shouldn't need to visit every page. I know you mentioned you've set the MIME type in Apache, but are you 100% certain it's working correctly?
You can check it by opening your manifest in a browser and checking the Response Headers in Chrome Web Inspectors's Network tab:
Content-Type should be text/cache-manifest
It's a bit hard to debug without having access to your site, but here's some instructions for how to interpret what happens in Chrome's Web Inspector with AppCache to help you debug the problem yourself:
The Resources tab will show you the contents and status of the Application Cache. It looks like this whilst it's downloading files:
The console will also log events when it's downloading:
Application Cache Progress event (0 of 48) http://cachedfile.url
Once it's done downloading it'll look like this and show you the list of cached files:
When you go back it'll log three events (assuming there aren't any changes):
Document was loaded from Application Cache with manifest http://manifest.url
Application Cache Checking event
Application Cache NoUpdate event
And then when you're offline it looks like this:
Hopefully between the console and the appcache table you'll be able to figure out what's happening.
The manifest file is correct and you do not need to visit each page to get in cache in your mobile. You could try if this is a problem with your mobile or browser and if you have defined in your server text/cache-manifest MIME type.
The appcache will only store the cache the first time it's downloaded. It's just a list of files that says, when it's downloaded the first time, cache it.
What you could do is after load in the background do an ajax call to load each of the intended resources but it's not particularly pretty.
So looks to me like it's acting how it should be.
CACHE:
This is the default section for entries. Files listed under
this header (or immediately after the CACHE MANIFEST) will be
explicitly cached after they're downloaded for the first time.
http://www.html5rocks.com/en/tutorials/appcache/beginner/
Ahmed
I get the following when visiting your site:
Creating Application Cache with manifest
http://www.iamaaron.com/appcache/example.appcache
Application Cache Checking event
Application Cache Downloading event
Application Cache Progress event (0 of 6)
http://www.iamaaron.com/appcache/styles/reset.css
Application Cache Progress event (1 of 6)
http://www.iamaaron.com/appcache/index.html
Application Cache Progress event (2 of 6)
http://www.iamaaron.com/appcache/contact.html
Application Cache Progress event (3 of 6)
http://www.iamaaron.com/appcache/attendees.html
Application Cache Progress event (4 of 6)
http://www.iamaaron.com/appcache/events.html
Application Cache Progress event (5 of 6)
http://www.iamaaron.com/appcache/styles/styles.css
Application Cache Error event: Resource fetch failed (404)
http://www.iamaaron.com/appcache/styles/styles.css
So, it looks like it's working correctly despite the Content-Type being empty, except for the CSS file which seems to be missing (the URL is wrong, it should be main.css by the looks of things).
BUT my developer tools don't show the app cache being filled and it doesn't work when it's offline.
Try and fix your 404 error with the CSS and make sure your apache it configured correctly to return the correct Content-Type, I reckon that's what's causing issues.
I am working on an HTML app for a client. The entire app front end is done with 1 HTML file, 1 Javascript file, 1 CSS file (plus jquery) and a few images. There are a few php scripts sitting on the server, which are called using AJAX, but only if an internet connection is available. If no connection is available, then the site will use locally cached data (using localStorage).
To make the site available offline, I'm declaring the cache manifest in my HTML. My HTML looks like this:
<!DOCTYPE html>
<html manifest="cache.manifest.php" language="en">
...
</html>
The cache.manifest.php's output look like this:
CACHE MANIFEST
#VersionHash: 80b9345e6c39efbbe8431e394b014b4f
CACHE:
/css/ebot.css
/favicon.ico
/images/appicon.png
/images/list-arrow.png
/images/list-checkmark.png
/images/woman.png
/index.html
/js/jquery-1.8.3.min.js
/js/ebot.ls.js
NETWORK:
/emaillog.php
/getdata.php
/uploadlog.php
So far so good. Now, I access the site from a browser with the internet connection available. I get a little notification asking whether to allow the site to store information for offline use - I allow it. When I check in settings, I see that the site stores 316K of data - about right.
Now I turn off internet connection and attempt to access http://www.mysite.com/index.html - and get an error message saying "Internet connection not available" (or something to that extent) and the page is not displayed. This is happening in 3 browsers I tested on my dev machine (firefox, safari and chrome) as well as on the client's ipad (the app is eventually for consumption on an ipad).
What am I missing here? What am I doing wrong?
There could be many reasons for this.
Take a look at this articles:
http://www.fuckyeahtml5.com/2011/06/debugging-html5s-offline-web-apps
http://appcachefacts.info/
http://diveintohtml5.info/offline.html
https://developer.mozilla.org/en/docs/HTML/Using_the_application_cache
I guess that you didn't specify proper content type (MIME) for your manifest. It shoud be 'text/cache-manifest'.
Check events in console in Chrome. You should see something like this when appcache manifest is correct:
Creating Application Cache with manifest http://example.com/manifest.appcache
Application Cache Checking event
Application Cache Downloading event
Application Cache Progress event (YYY of XXX)
Application Cache Cached event
I would suggest to start from the simplest manifest to make sure that manifest is parsed. Try:
CACHE MANIFEST
NETWORK:
*
such manifest should cache only your start html page.
I have a versioned cache manifest:
#version = e5b4271
Every time this version changes, my webapp loads the new manifest, but it never loads update files from the server. Even when I clear the browser cache (not the application cache itself), or hit Ctrl+Shift+R to force it to fetch a new version, it still loads the files from the old appcache.
The only way I can get it to update is to clear the browser's application cache in settings, but obviously this is unacceptable because I need it to update for regular users.
Any ideas why this would happen?
Just figured it out. I'm using Flask's development server, and it seems by default (via werkzeug) it sends cache headers for 12 hours for static files. Adding the following to my flask config solved this:
SEND_FILE_MAX_AGE_DEFAULT = -1
If anyone else has this issue, check your server config to make sure cache headers are not sent with static files. You can check this in the network tab in chrome during the first load of the file.
I'm testing offline web application in chrome 14. and listed some resource files in manifest such as:
CACHE MANIFEST
#version 1
./img/BG.jpg
./img/BtnDisable.gif
./img/BtnDown.gif
./img/BtnUp.gif
and after cache is loaded I replaced the "./img/BG.jpg" file to a new image, then changed the version of manifest file to 2, and finally refreshed page.
from the console, I can see "onprogress" event is triggered for each resource and finally "updateready" event is triggered. I called swapCache method in the listener of "updateready".
But after that , when I try to access "BG.jpg" in an Image tag or directly input it's URL in the address bar. the Image is still old "BG.jpg".
And I also found this issue in Safari 5.1. My web container is apache tomcat 7.
Do I misunderstand the offline mechanism and made some mistakes?
So How can I update the cached files of the client browser?
Try this:
CACHE MANIFEST
#version 2
./img/BG.jpg?v=2
./img/BtnDisable.gif?v=2
./img/BtnDown.gif?v=2
./img/BtnUp.gif?v=2