|For those who want to understand the power of the resource versioning approach that derives from Memento, this flip book movie is a fun illustration.
This is how it was created:
- For months, subtly changing "pictures of the day" were published that depict members of the Memento team posing next to a flip chart.
The changes are in the shirts, the timestamps, and the BBC or CNN content superimposed on the flip charts.
- At any moment in time, the current picture of the day is served from the following URIs:
- On a daily basis, these images are archived using a transactional archive approach.
As a result, old versions of these pictures become available at URIs like:
- Using the following script that targets the URI of a picture of the day (say http://lanlsource.lanl.gov/pics/picoftheday.png)
with incrementing datetime values for HTTP content negotiation and "follow your nose" HTTP navigation, all pictures of the day were gathered.
In essence, the URI is asked about its past, and the URI gracefully responds by pointing at a TimeGate that knows about its past,
and redirects to archived images that match the requested datetime values.
- The gathered pictures were then concatenated to obtain this flip book movie.