liburi-fetch-perl

_URI::Fetch_ is a smart client for fetching HTTP pages, notably syndication feeds (RSS, Atom, and others), in an intelligent, bandwidth- and time-saving way. That means: * * GZIP support If you have _Compress::Zlib_ installed, _URI::Fetch_ will automatically try to download a compressed version of the content, saving bandwidth (and time). * * _Last-Modified_ and _ETag_ support If you use a local cache (see the _Cache_ parameter to _fetch_), _URI::Fetch_ will keep track of the _Last-Modified_ and _ETag_ headers from the server, allowing you to only download pages that have been modified since the last time you checked. * * Proper understanding of HTTP error codes Certain HTTP error codes are special, particularly when fetching syndication feeds, and well-written clients should pay special attention to them. _URI::Fetch_ can only do so much for you in this regard, but it gives you the tools to be a well-written client. The response from _fetch_ gives you the raw HTTP response code, along with special handling of 4 codes: * * 200 (OK) Signals that the content of a page/feed was retrieved successfully. * * 301 (Moved Permanently) Signals that a page/feed has moved permanently, and that your database of feeds should be updated to reflect the new URI. * * 304 (Not Modified) Signals that a page/feed has not changed since it was last fetched. * * 410 (Gone) Signals that a page/feed is gone and will never be coming back, so you should stop trying to fetch it.