Offline mobile app has great potential!

1. Gaps between asset pipeline and rack-
offline
Let's hack together!

2. "Network operation did not complete in a
reasonable amount of time;
please retry"
"... I lost data?"

3. Cons
Cheap machine performance
Slow network speed

4. Meet html5 cache manifest
CACHE MANIFEST
index.html
stylesheet.css
images/masthead.png
scripts/misc.js
NETWORK:
search.php
login.php
/api
FALLBACK:
images/dynamic.php static_image.png
http://www.webreference.
com/authoring/languages/html/HTML5-Application-
Caching/index.html

5. Meet rack-offline
https://github.com/wycats/rack-offline
http://railscasts.com/episodes/247-
offline-apps-part-1
http://railscasts.com/episodes/248-
offline-apps-part-2

6. http://localhost:3000/application.manifest
CACHE MANIFEST
#
4470fbc3c8ac429d45368f5ad134fe7fee3f677f8d4994a5f04
407f8104e5e2f
assets/application.js Reflesh!
assets/application.css
404.html
422.html
500.html
index.html Detect!
public/*
NETWORK:
/

7. Meet jQuery-offline
jQuery.getJSON
↓
https://github.com/wycats/jquery-offline
jQuery.retrieveJSON

8. Store serialized data to local storage.
Send items background when network
recover, if you write so.

9. Meet after Rails3.1 & Asset Pipeline
sprockets manifest
app/assets/javascripts/application.js
//= require jquery
//= require jquery_ujs
//= require_tree .

10. Result,
Gap between rack-offline and asset
pipeline!
Keyword is sprockets.

11. Paths
> y Rails.application.config.assets.paths
---
- /Users/eifion/store/app/assets/images
- /Users/eifion/store/app/assets/javascripts
- /Users/eifion/store/app/assets/stylesheets
- /Users/eifion/store/lib/assets/greeting.txt
- /Users/eifion/store/vendor/assets/stylesheets
- /Users/eifion/.rvm/gems/ruby-1.9.2-
p180@railspre/gems/jquery-rails-1.0.13
/vendor/assets/javascripts
http://railscasts.com/episodes/279-understanding-the-
asset-pipeline

12. html5 cache manifest
list up all file names.
rack-offline seek and write hash. public/*

13. Engines
tilt pre-process
app/assets/javascripts/application.js #=> assets/application.js
app/assets/javascripts/items.js.coffee #=> assets/items.js
vendor/assets/javascripts/foo.js.erb #=> assets/foo.js
rubygems ;)

14. My temporary solution
https://gist.github.com/2200162
files = Dir[
"#{root}/assets/**/*.{js,css,jpg,png,gif}"]
files.each do |file|
cache Pathname.new(file).relative_path_from(root)
end

15. question in rubyonrails-talk
no response ;)
Offline apps and Asset pipeline Problem
in rails3.2
https://groups.google.com/forum/#!
msg/rubyonrails-
talk/nxCASUbmGYc/mI3IPvG3sOwJ

16. I should parse '//= jquery' and search
and get whether this is updated or not,
don't I?
It's too hard.
I think using sprockets and tilt solves my
problem, don't I?
I want example code.

17. This is grunt and/or watchr and/or
guard's solution area?
Or essentially offline app is client side
solution?
But asset pipeline is rails area, I think.

18. Mobile app is fun!

20. This is gap! Let's hack together!
@sanemat