I am working for a project which requires getting rss feed from a site (say amazon). The solution one i know is to use the url of the rss or xml file , but can anyone help me on getting rss feed without providing the url of rss or xml file , or is there any way exists to know the url of xml or rss of the site.
You can write a script that scrapes the html of specified sites & search for rss/xml files linked in them. They're usually specified in the home page of a website.
Don't do that. Not only will you be violating coyright laws, but you'll also be duplicating other sites' content, which will not only get your pages penalized by the search engines (if you're lucky) but can also get your site delisted by the search engines, and if your site is hosted on a server in the United Staes, even literally removed by a DMCA takedown notice. If you're going to reproduce an RSS feed, give proper attribution and be sure to read the feed creator's (host site) terms and conditions of use before syndicating their feed(s) on your Web site.