When creating a web app that is going to use the HTML5 app cache it can be painstaking to create the cache manifest file by hand. Not finding any tools that would do this as I wanted, I put together this simple script in Ruby that traverses any folder recursively and makes a note of each file. You can add specific files to be ignored and the specific file extensions to look for.
It also adds a comment with the time of creation. This is enough to trigger browsers to check the manifest contents as the file itself is different.
The proposed extension for manifest files is .appcache. However I found that iOS3 devices would ignore these files, so for fotb.me we used the .manifest extension. The file extension doesn't really matter as long as you are serving it up using the correct MIME type.
Manifests must be served using the text/cache-manifest MIME type. For Apache, simply add this to your .htaccess or config file:
AddType text/cache-manifest .appcache
To avoid expiry issues that may lead to insanity I suggest checking out the htaccessSample file.
- Edit
cacheManifestGenerator.rband ensure that thePATH,FILE_TYPESandIGNORE_FILESare set to your liking - In a Terminal window, navigate to the same path on your system
- Enter
ruby cacheManifestGenerator.rb
Once the manifest has been created, update your HTML file as follows:
<!DOCTYPE html>
<html manifest="/path/to/manifest/myManifest.appcache">
<head>
<meta charset="utf-8" />
<title>Sexy title</title>
</head>
<body>
Hi, I'm using a manifest and shit!
</body>
</html>
Automatically generating an HTML5 cache manifest - My blog post about this tool
Dive into HTML5 - Offline Web Applications
HTML5 Rocks - A Beginner's Guide to Using the Application Cache