The feed URI scheme was a suggested uniform resource identifier (URI) scheme designed to facilitate subscription to

web feed On the World Wide Web, a web feed (or news feed) is a data format used for providing users with frequently updated content. Content distributors ''Web syndication, syndicate'' a web feed, thereby allowing users to ''subscribe'' a channel to it b ...

s; specifically, it was intended that a

news aggregator In computing, a news aggregator, also termed a feed aggregator, feed reader, news reader, RSS reader or simply an aggregator, is client software or a web application that aggregates syndicated web content such as online newspapers, blogs, po ...

be launched whenever a

hyperlink In computing, a hyperlink, or simply a link, is a digital reference to data that the user can follow or be guided by clicking or tapping. A hyperlink points to a whole document or to a specific element within a document. Hypertext is text ...

to a feed URI was clicked in a

web browser A web browser is application software for accessing websites. When a user requests a web page from a particular website, the browser retrieves its files from a web server and then displays the page on the user's screen. Browsers are used on ...

. The scheme was intended to flag a document in a syndication format such as

Atom Every atom is composed of a nucleus and one or more electrons bound to the nucleus. The nucleus is made of one or more protons and a number of neutrons. Only the most common variety of hydrogen has no neutrons. Every solid, liquid, gas ...

RSS RSS ( RDF Site Summary or Really Simple Syndication) is a web feed that allows users and applications to access updates to websites in a standardized, computer-readable format. Subscribing to RSS feeds can allow a user to keep track of many di ...

. The document would be typically served over

HTTP The Hypertext Transfer Protocol (HTTP) is an application layer protocol in the Internet protocol suite model for distributed, collaborative, hypermedia information systems. HTTP is the foundation of data communication for the World Wide Web, ...

History

In 2006 the feed URI scheme was supported by several popular desktop aggregators, including NetNewsWire, FeedDemon,

Safari A safari (; ) is an overland journey to observe wild animals, especially in eastern or southern Africa. The so-called "Big Five" game animals of Africa – lion, leopard, rhinoceros, elephant, and Cape buffalo – particularly form an importa ...

, and Flock. no effort seems to be underway to officially register the scheme at

IANA The Internet Assigned Numbers Authority (IANA) is a standards organization that oversees global IP address allocation, autonomous system number allocation, root zone management in the Domain Name System (DNS), media types, and other Interne ...

. Critics hold that the purpose of the feed URI scheme is better served by

MIME type A media type (also known as a MIME type) is a two-part identifier for file formats and format contents transmitted on the Internet. The Internet Assigned Numbers Authority (IANA) is the official authority for the standardization and publication o ...

s, or that it is not a user-friendly solution for the problem of feed subscription, since a user who has not installed the appropriate software will receive an unhelpful browser error message on clicking a link to a feed URI. The feed URI scheme was suggested in 2003 in and . These expired drafts were not submitted as Internet drafts; the author later contributed to the work on the atom standard.

Syntax

The syntax for a feed URI may be expressed in

Backus–Naur form In computer science, Backus–Naur form () or Backus normal form (BNF) is a metasyntax notation for context-free grammars, often used to describe the syntax of languages used in computing, such as computer programming languages, document format ...

as follows: ::= "feed:" , "feed://"

Specifically, a feed URI may be formed from any absolute URI (such as an absolute

URL A Uniform Resource Locator (URL), colloquially termed as a web address, is a reference to a web resource that specifies its location on a computer network and a mechanism for retrieving it. A URL is a specific type of Uniform Resource Identifie ...

) by prepending feed, and as a special case, may be formed from any absolute

http 





The Hypertext Transfer Protocol (HTTP) is an application layer protocol in the  Internet protocol suite model for distributed, collaborative, hypermedia information systems. HTTP is the foundation of data communication for the  World Wide Web, ...

URI by replacing the initial http:// with feed://. The and constructs in the syntax are specified in RFC 3986 also known as

STD Sexually transmitted infections (STIs), also referred to as sexually transmitted diseases (STDs) and the older term venereal diseases, are infections that are spread by sexual activity, especially vaginal intercourse, anal sex, and oral sex ...

66. Here is in essence the part of the original http URI, and is the following absolute path introduced by a slash ""; it can be empty or absent. Therefore, the following are two examples of valid feed URIs: feed:https://example.com/entries.atom feed://example.com/entries.atom

References

{{DEFAULTSORT:Feed Uri Scheme URI schemes Web syndication Proposals