Outline Processor Markup Language

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OPML
Opml-icon.svg
File extension : .opml
MIME type : application / xml, text / xml, text / x-opml
Type: Outline
Extended by: XML
Website : dev.opml.org


Outline Processor Markup Language ( OPML ) is an XML format that is used to exchange structured information. It was developed by Radio UserLand and initially served primarily to depict outlines , i.e. hierarchically structured texts that can be displayed and edited with an outline editor .

One of the best known applications of OPML is now the automated exchange of RSS - web feeds between the RSS aggregators .

In March 2006, an expanded specification was put up for discussion with OPML 2.0, which contains some new functionalities, including: a. the include type , ownerId and support for namespaces .

XML format

The XML elements of an OPML document are:

<opml version="1.0">
That is the main element. It must contain the version attribute, an <head>and an <body>element.
<head>
Contains metadata . Can contain the following optional elements: <title>, <dateCreated>, <dateModified>, <ownerName>, <ownerEmail>, <expansionState>, <vertScrollState>, <windowTop>, <windowLeft>, <windowBottom>, <windowRight>. Each element is a simple text element. <dateCreated>and <dateModified>contain a date format that conforms to that specified in RFC 822 . <expansionState>Contains a comma-separated list of line numbers that should expand on the display. The element <windowXXX>defines the position and size of the displayed window. An OPML processor can <head>ignore all sub-elements. If the outline is opened within another outline, the processor must <window>ignore the elements.
<body>
Contains the content of the outline. Must <outline>contain one or more elements.
<outline>
Represents one line in the output. Can contain any number of attributes. Common attributes include textand type. The element <outline>can contain any number of <outline>sub-elements.
In the case of RSS feeds containing <outline>element's attributes title, textif necessary htmlUrl, as well type="rss", and xmlUrlto designate the feed itself.

See also

Web links