If a website is offline or restricts how quickly it can be crawled then downloading from someone else’s cache can be necessary. In previous posts I discussed using Google Translate and Google Cache to help crawl a website. Another useful source is the Wayback Machine at archive.org, which has been crawling and caching webpages since 1998.
Here are the list of downloads available for a single webpage, amazon.com:
Or to download the webpage at a certain date:
|Jan 1st, 2011:||http://web.archive.org/web/20110101/http://www.amazon.com/|
The webscraping library includes a function to download webpages from the Wayback Machine. Here is an example:
This example downloads the same webpage directly and via the Wayback Machine. Then it parses the title to show the same webpage has been downloaded. The output when run is:
Amazon.com: Online Shopping for Electronics, Apparel, Computers, Books, DVDs & more Amazon.com: Online Shopping for Electronics, Apparel, Computers, Books, DVDs & more