Templates

Template names take the form name.ext.type, where name.ext identifies the name of the output file to be created in the output_directory, and type indicates which language processor to use for the template.

Like with filters, templates may be written in a variety of languages and are based on the standard Unix pipe convention of producing stdout from stdin, but in practice two languages are used more than others:

htmltmpl

Many find htmltmpl easier to get started with as you can take a simple example of your output file, sprinkle in a few <TMPL_VAR>s and <TMPL_LOOP>s and you are done. Eventually, however, you may find that your template involves <TMPL_IF> blocks inside of attribute values, and you may find the result difficult to read and create correctly.

It is also important to note that htmltmpl based templates do not have access to the full set of information available in the feed, just the following (rather substantial) subset:

VAR	type	source
author	String	author
author_name	String	author_detail.name
generator	String	generator
id	String	id
icon	String	icon
last_updated_822	Rfc822	updated_parsed
last_updated_iso	Rfc3399	updated_parsed
last_updated	PlanetDate	updated_parsed
link	String	link
logo	String	logo
rights	String	rights_detail.value
subtitle	String	subtitle_detail.value
title	String	title_detail.value
title_plain	Plain	title_detail.value
url	String	links[rel='self'].href
		headers['location']

Note: when multiple sources are listed, the last one wins

In addition to these variables, Planet Venus makes available two arrays, Channels and Items, with one entry per subscription and per output entry respectively. The data values within the Channels array exactly match the above list. The data values within the Items array are as follows:

VAR	type	source
author	String	author
author_email	String	author_detail.email
author_name	String	author_detail.name
author_uri	String	author_detail.href
content_language	String	content[0].language
content	String	summary_detail.value
		content[0].value
date	PlanetDate	published_parsed
		updated_parsed
date_822	Rfc822	published_parsed
		updated_parsed
date_iso	Rfc3399	published_parsed
		updated_parsed
enclosure_href	String	enclosures[0].href
enclosure_length	String	enclosures[0].length
enclosure_type	String	enclosures[0].type
guid_isPermaLink	String	isPermaLink
id	String	id
link	String	links[rel='alternate'].href
new_channel	String	id
new_date	NewDate	published_parsed
		updated_parsed
rights	String	rights_detail.value
title_language	String	title_detail.language
title_plain	Plain	title_detail.value
title	String	title_detail.value
summary_language	String	summary_detail.language
updated	PlanetDate	updated_parsed
updated_822	Rfc822	updated_parsed
updated_iso	Rfc3399	updated_parsed
published	PlanetDate	published_parsed
published_822	Rfc822	published_parsed
published_iso	Rfc3399	published_parsed

Note: variables above which start with new_ are only set if their values differ from the previous Item.

xslt

XSLT is a paradox: it actually makes some simple things easier to do than htmltmpl, and certainly can make more difficult things possible; but it is fair to say that many find XSLT less approachable than htmltmpl.

But in any case, the XSLT support is easier to document as the input is a highly normalized feed, with a few extension elements.

• atom:feed will have the following child elements:
  • A planet:source element per subscription, with the same child elements as atom:source, as well as an additional child element in the planet namespace for each configuration parameter that applies to this subscription.
  • planet:format indicating the format and version of the source feed.
  • planet:bozo which is either true or false.
• atom:updated and atom:published will have a planet:format attribute containing the referenced date formatted according to the [planet] date_format specified in the configuration