Webmonitor - an Online Service to Monitor Webpage Changes

Abstract

Many websites like newspapers, product comparison websites may need to update information regularly based on the webpages of other websites. For that they need to compare new version of the webpage with the old version of the same webpage and find the difference. One of the best ways to do this is to show the two versions side by side in two iframes and highlight the changes in different colors. Currently there are some open source solutions to highlight the changes between 2 different texts but for comparing webpages these programs are not useful at all because for webpages we need to ignore the HTML, CSS, JavaScript code first. This fact inspired me to create this application, which will act as a webservice. It also has subscribing, login and user administration facility. So, multiple users can create accounts and also multiple admins can use this program to manage the user accounts. This program also lists the changes of many websites on a page like a summary after sorting the result. Users can add webpages or remove webpages or entire websites from monitoring. Finally, it has functions which can be used with cron job on a php web-server. When cron job is used, it will periodically monitor the webpages and list the webpages which have changes.