notes.txt

* Going to talk about the HTML5 features I have worked with personally

* Web application that acted as a script for an interview. 
* The application captured answers and comments
* Wanted to be able to do the interviews at people's apartments where internet might not be available or would be spotty if available.

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Web Storage - What
* Domain specific - You don't have to do anything to keep data from one site separate from another site
* Keys and values are stored as strings, so JSON encoding is very useful

Session Storage
* Each browser tab and window has its own session storage

Local Storage
* Data remains after browser is closed

My Uses
* Cached:
 * the questions that made up the interview
 * previous answers
 * application configuration data
 
Multi-user computer
* LocalStorage doesn't know anything about users logging into an application
* Values are stored with whatever keys they are given

Schema changes
* Multiple choice answers might have changed since the interview was done offline
 - break single choice into two, or combine two into one
* Field added, removed, or renamed in a core data structure
  
  Migrations
   * Used version numbers to know when changes needed to be applied to data that 
     had been stored in local storage
     
Private information
* Talking about sensitive information that shouldn't be available in plain text
* Used a javascript encryption library (Block TEA - Tiny Encryption Algorithm)

Synchronization
* Interview answers that were captured offline needed to be saved on the server 
  after coming back online

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Application Cache - What
* If a file is in the application cache the browser does not go out to the internet to look for a new version

Cache Manifest
* The cache manifest is where the browser finds out what files to store in its application
  cache
  
Sample Cache Manifest
* Browser only updates when the manifest changes. Use a timestamp, version number to indicate a change
* I used an MD5 digest of the files included in the cache - if any of those files changed the digest would
  change causing a browser to download the new manifest.
  
Simulating Offline
* Firefox - easy to disconnect and reconnect

Annoying Double Refresh
  * Pain to refresh, wait for new files to be stored, then refresh again.