OPDS

OPDS (Open Publication Distribution System) is a family of specifications dedicated to the distribution of digital publications. The OPDS Catalog format is a syndication format for electronic publications based on Atom and HTTP. OPDS Catalogs enable the aggregation, distribution, discovery, and acquisition of electronic publications.

Regarding specifications, the official OPDS website states that

The historical version of OPDS (1.x) is based on Atom and Dublin Core, while the current draft (2.0) is based on JSON-LD and schema.org.

The OPDS specs would allow Thoth to publish a syndication feed that pushes out updates to the metadata catalog through a so-called Acquisition feed. This feed includes Dublin Core specifications in an XML format:

<?xml version="1.0" encoding="UTF-8"?>
<feed xmlns="http://www.w3.org/2005/Atom"
      xmlns:dc="http://purl.org/dc/terms/"
      xmlns:opds="http://opds-spec.org/2010/catalog">
  <id>urn:uuid:433a5d6a-0b8c-4933-af65-4ca4f02763eb</id>

  <link rel="related"
        href="/opds-catalogs/vampire.farming.xml"
        type="application/atom+xml;profile=opds-catalog;kind=acquisition"/>
  <link rel="self"    
        href="/opds-catalogs/unpopular.xml"
        type="application/atom+xml;profile=opds-catalog;kind=acquisition"/>
  <link rel="start"  
        href="/opds-catalogs/root.xml"
        type="application/atom+xml;profile=opds-catalog;kind=navigation"/>
  <link rel="up"      
        href="/opds-catalogs/root.xml"
        type="application/atom+xml;profile=opds-catalog;kind=navigation"/>

  <title>Unpopular Publications</title>
  <updated>2010-01-10T10:01:11Z</updated>
  <author>
    <name>Spec Writer</name>
    <uri>http://opds-spec.org</uri>
  </author>

  <entry>
    <title>Bob, Son of Bob</title>
    <id>urn:uuid:6409a00b-7bf2-405e-826c-3fdff0fd0734</id>
    <updated>2010-01-10T10:01:11Z</updated>
    <author>
      <name>Bob the Recursive</name>
      <uri>http://opds-spec.org/authors/1285</uri>
    </author>
    <dc:language>en</dc:language>
    <dc:issued>1917</dc:issued>
    <category scheme="http://www.bisg.org/standards/bisac_subject/index.html"
              term="FIC020000"
              label="FICTION / Men's Adventure"/>
    <summary>The story of the son of the Bob and the gallant part he played in
      the lives of a man and a woman.</summary>
    <link rel="http://opds-spec.org/image"    
          href="/covers/4561.lrg.png"
          type="image/png"/>
    <link rel="http://opds-spec.org/image/thumbnail"
          href="/covers/4561.thmb.gif"
          type="image/gif"/>

    <link rel="alternate"
          href="/opds-catalogs/entries/4571.complete.xml"
          type="application/atom+xml;type=entry;profile=opds-catalog"
          title="Complete Catalog Entry for Bob, Son of Bob"/>

    <link rel="http://opds-spec.org/acquisition"
          href="/content/free/4561.epub"
          type="application/epub+zip"/>
    <link rel="http://opds-spec.org/acquisition"
          href="/content/free/4561.mobi"
          type="application/x-mobipocket-ebook"/>
 </entry>

 <entry>
    <title>Modern Online Philately</title>
    <id>urn:uuid:7b595b0c-e15c-4755-bf9a-b7019f5c1dab</id>
    <author>
      <name>Stampy McGee</name>
      <uri>http://opds-spec.org/authors/21285</uri>
    </author>
    <author>
      <name>Alice McGee</name>
      <uri>http://opds-spec.org/authors/21284</uri>
    </author>
    <author>
      <name>Harold McGee</name>
      <uri>http://opds-spec.org/authors/21283</uri>
    </author>
    <updated>2010-01-10T10:01:10Z</updated>
    <rights>Copyright (c) 2009, Stampy McGee</rights>
    <dc:identifier>urn:isbn:978029536341X</dc:identifier>
    <dc:publisher>StampMeOnline, Inc.</dc:publisher>
    <dc:language>en</dc:language>
    <dc:issued>2009-10-01</dc:issued>
    <content type="text">The definitive reference for the web-curious
      philatelist.</content>
    <link rel="http://opds-spec.org/image"    
          href="/covers/11241.lrg.jpg"
          type="image/jpeg"/>

    <link rel="http://opds-spec.org/acquisition/buy"
          href="/content/buy/11241.epub"
          type="application/epub+zip">
      <opds:price currencycode="USD">18.99</opds:price>
      <opds:price currencycode="GBP">11.99</opds:price>
    </link>
 </entry>
</feed>

Accessibility

There are no accessibility sections associated with this metadata standard.