Create a new Rails app that keeps track of the user agents used to access it.
The user agent string should be saved in a table in the database, one entry for each unique user agent string. The table should also have a counter and 2 timestamps, one for the first time the user agent was seen, and one for the last time.
For each page request, increment the counter and set the timestamps appropriately. (Do not worry about the extra db overhead to access the user agent table on each request; this is an artificial scenario.)
Add an index page that shows a sorted list of user agents and their timestamps and counters.
Add a button to the index page that uses ajax to refresh the table from the server without doing a complete page refresh.
(( This exercise should not take too long. If you find yourself going over an hour, stop and send what you have so far. ))