Automating a Web Head's Up

March 28, 2011 10:33 AM

How I do know when a specific part of a specific page is updated on the web? I want to take advantage of an online sale, so I need to be notified when the deal is available...

Lollapalooza is going to have a $60/3-day-ticket sale. I buy a ticket every year for a friend as a birthday gift, and I'd like to grab one in whatever short window that sale is available (he's worth the c. $180, but hell, why not save it if I can?).

The home page of their site right now shows a "before" div; there's an "onsale" and a "soldout" that are commented out. The key component appears to be an image tag:

<img class="pbtn" src="http://lolp1.c3cdn.com/timecapsule/splash_assets/images/lollapalooza_tix_now_btn.png" />

I figure I need a {timer function thing} that looks every n seconds to see if that specific image is visible. Or... something else.

I'm open to any suggestions for monitoring that site to get the sale price. Let's assume I do not have write access to a web server, but that client-side javascript would work. Also, if there's an existing tool or service on the Intarwebs that will do this, that would be fine, too.

posted by OneMonkeysUncle to computers & internet (7 answers total)

http://femtoo.com/

Check that out.
posted by babble at 10:43 AM on March 28, 2011

I use http://www.watchthatpage.com - It informs me once per day if a site has had changes to the page I specify. Works like a charm. :)
posted by Vamier at 11:44 AM on March 28, 2011

If you're using Firefox, then Check4Change is exactly what you need. Highlight what you want it to check for and tell it how often to check. Make sure your sound is on, it plays a snippet of David Bowie to let you know when there are changes.

3 guess on what song. And yes, if you hate it you can change it if it bothers you that much.
posted by theichibun at 12:11 PM on March 28, 2011 [1 favorite]

There's a program called WebMon (Windows) that I use to monitor changes in web pages. It allows you to specify certain parts of the page HTML to check for changes, so it will probably work in your case. Note that the minimum amount of time in which it will preform checks is every 1 minute.
posted by upplepop at 2:27 PM on March 28, 2011

I wrote a program to send myself a text when it changes. MeMail me your cell phone number and I can add you as well if you want. Note: this may not work or could result in a false alarm.
posted by burnmp3s at 7:38 AM on March 29, 2011

Many thanks to burnmp3s for their help - but even with a text message within 15 seconds of the site being updated, I still wasn't fast enough to beat the scalper's bots...
posted by OneMonkeysUncle at 12:37 PM on March 29, 2011

By the time the waiting system let me in they were all gone. Apparently they sold out in around 45 seconds.
posted by burnmp3s at 1:14 PM on March 29, 2011