RSS & Feeds
网页设计与编程 第 12讲
问题的起源
有同学发来邮件,
? 如何在网站中,同步发表或者引用其他网站
发布的新闻 /消息?
? 以下的内容主要回答这个问题,
What is RSS?
RSS is a text-based format,a type of
XML,
You should know that only because
often RSS files are often labeled as XML,
What is RSS?
RSS version 1.0 is also RDF (whatever),
which,again,is important only because
an RSS file may be labeled as RDF,
RSS files (which are also called RSS
feeds or channels) simply contain a list
of items.
What is RSS?
Usually,each item contains a title,
summary,and a link to a URL (e.g,a
web page),
The most common use for RSS files is
for news and other reverse-
chronologically ordered websites like
blogs.
What is RSS?
When a website has an RSS feed,it is
said to be,syndicated.”
RSS files do not have a common file
extension,although they frequently end
in one of,xml,.rss,or,rdf
What is RSS?
If you are interested in creating RSS
feeds,see this RSS Workshop,or Atom
for Publishers for Atom.
If you are interested in creating an RSS
or Atom reader,see the Aggregators
Yahoo! group.
Glossary
RSS
? Really Simple Syndication
? Rich Site Summary
? RDF Site Summary
RSS file
? RSS feed
? RSS channel
? feed
? channel
Glossary
XML
? eXtensible Markup Language
? the format RSS is written in
? important only because RSS may be labeled as
XML
RDF
? Resource Discovery Framework
? the format of RSS version 1.0
? important only because RSS may be labeled as
RDF
Glossary
blog
? weblog
? log on the web
? a journal-type website,many of which
produce RSS feeds
Glossary
RSS reader
? news reader
? RSS aggregator
? a program that can read RSS files
What Can I do with RSS?
displaying headlines on other websites
search engines
aggregating RSS feeds from multiple
websites
Displaying Headlines on
Other Websites
Quite a few websites use RSS to display
headlines from other websites,as it
provides additional content to their
readers,
Below is displayed the last seven front-
page news headlines from the BBC,The
BBC has 68 RSS feeds available,
Search Engines
RSS-based search engines can index
individual items rather than pages
which may contain many items,
There are several good general-purpose
RSS-based search engines around today;
they are available on Fagan Finder on
the Weblogs,Journals,and RSS page,
RSS Aggregators
Why Use an RSS
Aggregator?
For anyone that reads a half dozen or
more pages that have RSS feeds,an
aggregator is a necessity,
RSS aggregators are set up to
periodically check for new items in the
feeds you are subscibed to,commonly
once every hour,
Why Use an RSS
Aggregator?
This saves a tremendous amount of
time,Or conversely,you can read many
more feeds in the same ammont of time,
Many people read several hundred
feeds,That just wouldn’t be feasible
without an RSS aggregator,
Why Use an RSS
Aggregator?
Additionally,you avoid all the non-new
information on a web page,including
the ads,menus,etc.
Subscribing to a Feed
There is no agreed-upon standard for
how to subscribe to an RSS feed,
There are roughly two ways to
subscribe,
? One is to enter the URL of the RSS feed
into your aggregator,
? The other is to follow a subscribe link from
a web page
Finding the RSS Feed for a
Website
The websites you already read may
have an RSS feed,So you want to find
it,
Go to Feedster tool and enter in a
website,It will return the feed for you,
Finding the RSS Feed for a
Website
The most common is an XML icon like
this:,but there are a number of
variations on label (RSS,RSS2,XML,
RDF,Atom),colour,and size,such as
and,
Other times there may not be an image,
but text with one of those lables,or a
link labeled,Syndicate this site.”
Miscellaneous
? GeoURL has a database of websites along
with the physical location (latitude and
longitude) that the website (or creator)
lives in,
? Many,but not all of the websites are blogs,
? Click on the map,and you will see a listing
of websites within 500 miles of the spot
you choose,
Miscellaneous
? SourceForge is a gigantic software
development website,where thousands of
open source projects are developed,
? SourceForge itself has a number of RSS
feeds,as does every single project,
Miscellaneous
? myRSS allows you to create RSS feeds for
websites that don’t already have them,
? The scraping (see paragraph two of this
page) isn’t perfect,but it works well for
many sites,
? It is free,but only updates once a day and
shows self advertising,unless you sponsor
them,
Miscellaneous
? So,it would still be a good idea to e-mail
the webmasters and ask them to create an
RSS feed,
? People have already used myRSS to create
lots of feeds,you can search,browse using
DMOZ categories,and check out the top
100 RSS feeds by popularity,
小结
什么是新闻同步 /RSS/FEED(s)
如何获取 FEED(s)
如何应用 FEED---
(SharperReader/PustNoke)