WebSelF: A Web Scraping Framework

We present, WebSelF, a framework for web scraping which models the process of web scraping and decomposes it into four conceptually independent, reusable, and composable constituents. We have validated our framework through a full parameterized implementation that is flexible enough to capture previous work on web scraping. We have experimentally evaluated our framework and implementation in an experiment that evaluated several qualitatively different web scraping constituents (including previous work and combinations hereof) on about 11,000 HTML pages on daily versions of 17 web sites over a period of more than one year. Our framework solves three concrete problems with current web scraping and our experimental results indicate that com- position of previous and our new techniques achieve a higher degree of accuracy, precision and specificity than existing techniques alone.