IT360 Notes – Ajax in the Real World Part 2

Part two of the seminar. Lots of code I won’t paste. Also explains some of the tools used.

• firebug at getfirebug.com
• allows you to expand the DOM at the bottom pane, the active element is then highlighted at the viewing pane
• also good for css because you can look and see the css for a particular element at the side pane and where it’s inherited from (note to self, get firebug for this reason)
• console lets you see the XHRs including headers and params, also gives you the latency and what objects and files made the request
• can insert debug logs for firebug using console.log() call, be sure to strip this out later
• firebug’s console is interactive which lets you test things more easly
• using divs is a nice way to attach styles to items, to hide individual items, etc
• cache files can be important to take load off the database where applicable, downside is it can slow down propagation of data to other users
• PHP specific: fopen locks files, might have issues when someone reqs cache file at same time you write
• be wary of XSS, injection, etc
  • validate anything that gets passed to the database
  • ensure that if a user can display code to another user, it prevents scripting which would otherwise allow the same cookie permissions as your site