Atom Feed Metadata Documentation

Appendix 1: Key Information about Wavelength Atom Feeds

feed / subtitle

Example:

<subtitle>Items 1 to 10 out of 31 items. Filtered by: (1) Educational Level = Informal education; (2) Topics/Subjects = Earth and space science:Astronomy:Stars, nebulae and galaxies</subtitle>

Description:

The <subtitle> element has information about the search filters used to select the resources indexed by Wavelength.

feed / updated

Example:

<updated>2014-01-30T17:16:14Z</updated>

Description:

The <updated> element indicates when Wavelength was last updated. Results of searches are current as of this date.

feed / opensearch:totalResults

Example:

<opensearch:totalResults>31</opensearch:totalResults>

Description:

The <opensearch:totalResults> element indicates the total number of resources found in the search of Wavelength. This number may be much bigger than the number of resources expressed in a given feed. If so, then the feed will have links to page through large numbers of search results.

feed / link [@rel = “alternate” AND @type=”text/html”]

Example:

<link rel="alternate" type="text/html" title="Wavelength Search Results" href="http://nasawavelength.org/resource-search?qq=&amp;facetSort=1&amp;educationalLevel=Informal+education&amp;topicsSubjects=Earth+and+space+science%3AAstronomy%3AStars%2C+nebulae+and+galaxies&facetSort=1"/>

Description:

This <link> element provides the URL to the HTML representation of the feed (search results) at the Wavelength website. Note that the “&” characters are escaped so as to be valid XML. They need to be unescaped in order for the Wavelength website to recognize the search and filter parameters.

feed / link [@rel = “next”]

Example:

<link rel="next" href="http://api.nasawavelength.org/search/cow-facets-atom?qq=&amp;facetSort=1&amp;educationalLevel=Informal+education&topicsSubjects=Earth+and+space+science%3AAstronomy%3AStars%2C+nebulae+and+galaxies&amp;facetSort=1&amp;page=2"/>

Description:

Wavelength supports Atom feed paging to enable navigation of long lists of results. The <link> element in the example above provides the URL to the next page of results, as expressed in an Atom feed. Similarly links with rel = ‘previous’ navigate to the previous page of Atom expressed search results. The rel = ‘first’ points to the first page, and rel = ‘last’ is the last page.

Appendix 2: Key Information about Wavelength Atom Feed Entries

feed / entry / title

Example:

<title>Stellar Evolution: Our Cosmic Connection</title>

Description:

The <title> element contains the title of the resource in the search results.

feed / entry / update

Example:

<updated>2013-04-03T15:49:22Z</updated>

Description:

The <updated> element indicates when Wavelength last update metadata (descriptive information) about this resource.

feed / entry / published

Example:

<published>2012-06-15T07:00:00Z</published>

Description:

The <published< element indicates when the resource with published, as best determined by Wavelength digital librarians.

feed / entry / id

Example:

<id>http://chandra.harvard.edu/edu/formal/stellar_ev/teachers_guide.html</id>

Description:

This <id> element identifies the resource found in the Wavelength search. In most cases, the ID is the URL of the resource.

feed / entry / link [@rel = “alternate” AND @type=”text/html”]

Example:

<link rel="alternate" type="text/html" href="http://chandra.harvard.edu/edu/formal/stellar_ev/teachers_guide.html"/>

Description:

The <link> element in the example above provides the URL to the resource found in a Wavelength search. In this case the resource is a webpage (type = “text/html”). In some other cases, the resource may be a PDF document, in which case it will have type = “application/pdf”.

feed / entry / link [@rel = “describedby” AND @type=”application/xml”]

Example:

<link rel="describedby" type="application/xml" href="http://cow.lhs.berkeley.edu/ncs/services/ddsws1-1?verb=GetRecord&amp;id=nw-000-000-003-127"/>

Description:

The <link> element in the example above provides a URL to the XML metadata description of the resource found in a Wavelength search. The metadata uses the DLESE standard (http://www.dlese.org/Metadata/). Note that the “&” characters are escaped so as to be valid XML. They need to be unescaped in order for the Wavelength website to recognize the search and filter parameters.

feed / entry / category

Example:

<category term="Earth and space science:Astronomy:Stars, nebulae and galaxies"/>

Description:

The <category> element has an attribute, term, that contains descriptive metadata about the resource presented as plain-text key words. To get these metadata as XML structured data, see the discussion above.

feed / entry / author / name

Example:

<author>
	<name>Smithsonian Astrophysical Observatory (SAO)/Chandra X-Ray Center</name>
</author>
				

Description:

The <author><name> elements provide information about the creators of a resource as plain text. To get these metadata as XML structured data, see the discussion above.

feed / entry / summary

Example:

<summary>In this activity, students use multi-wavelength images of stars in different stages of evolution: to investigate how the initial masses of the protostars...</summary>

Description:

The <summary> element provides a plain text summary of what the resource is about.