The 'iffy' XML namespace

➣  This post was meaningfully revised at 2024-05-25 @ 11:00 PM EDT. The previous revision is here.
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I want to do a lot of things with RSS that require extensions of RSS (as the RSS spec foresees).

The URL http://tech.interfluidity.com/xml/iffy/ will mark an XML namespace in which some of these extensions will be defined.

The conventional prefix associated with this namespace will be iffy.

The current version of this namespace is v0.0.1-SNAPSHOT.

(-SNAPSHOT signifies that the version preceding that suffix has not yet been finalized. Much more to come!)

Table of Contents

Element — iffy:completeness

Solely a channel level element

Contains one of the following four values:

  1. Ping
  2. Metadata
  3. Content
  4. Media

iffy:completeness describes the completeness that clients should expect of RSS item elements.

  • Ping makes the least commitment. Items need not include a guid element, or any elements at all beyond RSS' requirement that at least one of title or description be present. RSS documents have completion Ping by default. Any or all items may meet the requirement for a higher completeness level, but no promises or commitment is made beyond the base specification.

  • Metadata commits that each item MUST include a guid element, as well as meeting the base requirements for an RSS item.

  • Content commits that each item, either inside its description tag, or via an extension such as content:encoded, includes the full content of the items it includes, suitable for independent rendering by any client capable also of resolving references to linked media externally. No limitation is placed on whether the full content is placed in a description element, in content:encoded, or in some other extension.

  • Media augments Content by embedding attachments to subsidiary media inside the RSS document. Subsidiary media does not include all potential links, just links which share a prefix with the current RSS document, which by default means all links subsidiary to the parent of the RSS document as specified in an atom:link

    More information on this soon when iffy:attachment is defined

The four values represent nested, hierarchical levels of commitment. Ping commits to nothing more than the spec requires. Media makes every commitment promised by the prior three levels, and an additional one.

If not specified, no commitment is made, the feed should be considered Ping.


<?xml version='1.0' encoding='UTF-8'?>

<rss version="2.0" xmlns:iffy="http://tech.interfluidity.com/xml/iffy/" xmlns:atom="http://www.w3.org/2005/Atom" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:content="http://purl.org/rss/1.0/modules/content/">
    <title>tech — interfluidity</title>
    <atom:link type="application/rss+xml" rel="self" href="https://tech.interfluidity.com/feed/index.rss"/>
    <!-- Other channel elements -->
      <!-- Other item elements -->

Element — iffy:provenance

When an item level element

If present in an item, the item contains a sequence of one or more atom:link elements, each of whose

  • rel attribute is MUST BE via
  • href attribute MUST BE the URL of an RSS feed from which the base contents of this item were drawn
  • type attribute SHOULD BE application/rss+xml

If the item from which the current item was sourced does not contain an iffy:provenance, then the current item should include just one atom:link.

If the item from which the current item was sourced does contains an iffy:provenance, then the current feed SHOULD include all items of that element, with the URL of the feed from which the item was sourced PREPENDED.

This will ensure the most immediate source will be the first atom:link element. The origin — or at least the source for which no further provenance is known — will be the last atom:link element.

Processors may expect a channel level atom:link element with rel="self" and type="application/rss+xml" to use as the basis for provenance in source documents. See RSS Best Practices.

Example (from here):

<?xml version='1.0' encoding='UTF-8'?>

<rss version="2.0" xmlns:iffy="http://tech.interfluidity.com/xml/iffy/" xmlns:sy="http://purl.org/rss/1.0/modules/syndication/" xmlns:slash="http://purl.org/rss/1.0/modules/slash/" xmlns:atom="http://www.w3.org/2005/Atom" xmlns:wfw="http://wellformedweb.org/CommentAPI/" xmlns:content="http://purl.org/rss/1.0/modules/content/" xmlns:dc="http://purl.org/dc/elements/1.1/">
    <title>interfluidity, all blogs</title>
    <!-- Other channel elements -->
    <atom:link type="application/rss+xml" rel="self" href="https://www.interfluidity.com/unify-rss/all-blogs.rss"/>
      <title>Industrial policy and ecosystems</title>
      <guid isPermalink="true">https://drafts.interfluidity.com/2024/05/11/industrial-policy-and-ecosystems/index.html</guid>
      <author>nospam@dev.null (Steve Randy Waldman)</author>
      <!-- Other item elements -->
        <atom:link type="application/rss+xml" rel="via" href="https://drafts.interfluidity.com/feed/index.rss"/>

Major revisions:

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