podcastparser

podcastparser is a simple and fast podcast feed parser library in Python. The two primary users of the library are the gPodder Podcast Client and the gpodder.net web service.

The following feed types are supported:

The following specifications are supported:

These formats only specify the possible markup elements and attributes. We recommend that you also read the Podcast Feed Best Practice guide if you want to optimize your feeds for best display in podcast clients.

Where times and durations are used, the values are expected to be formatted either as seconds or as RFC 2326 Normal Play Time (NPT).

Example

import podcastparser
import urllib

feedurl = 'http://example.com/feed.xml'

parsed = podcastparser.parse(feedurl, urllib.urlopen(feedurl))

# parsed is a dict
import pprint
pprint.pprint(parsed)

Supported XML Elements and Attributes

For both RSS and Atom feeds, only a subset of elements (those that are relevant to podcast client applications) is parsed. This section describes which elements and attributes are parsed and how the contents are interpreted/used.

RSS

rss@xml:base

Base URL for all relative links in the RSS file.

rss/channel

Podcast.

rss/channel/title

Podcast title (whitespace is squashed).

rss/channel/link

Podcast website.

rss/channel/description

Podcast description (whitespace is squashed).

rss/channel/image/url

Podcast cover art.

rss/channel/itunes:image

Podcast cover art (alternative).

rss/channel/atom:link@rel=payment

Podcast payment URL (e.g. Flattr).

rss/channel/item

Episode.

rss/channel/item/guid

Episode unique identifier (GUID), mandatory.

rss/channel/item/title

Episode title (whitespace is squashed).

rss/channel/item/link

Episode website.

rss/channel/item/description

Episode description. If it contains html, it’s returned as description_html. Otherwise it’s returned as description (whitespace is squashed). See Mozilla’s article Why RSS Content Module is Popular

rss/channel/item/itunes:summary

Episode description (whitespace is squashed).

rss/channel/item/itunes:subtitle

Episode subtitled / one-line description (whitespace is squashed).

rss/channel/item/content:encoded

Episode description in HTML. Best source for description_html.

rss/channel/item/itunes:duration

Episode duration.

rss/channel/item/pubDate

Episode publication date.

rss/channel/item/atom:link@rel=payment

Episode payment URL (e.g. Flattr).

rss/channel/item/atom:link@rel=enclosure

File download URL (@href), size (@length) and mime type (@type).

rss/channel/item/itunes:image

Episode art URL.

rss/channel/item/media:content

File download URL (@url), size (@fileSize) and mime type (@type).

rss/channel/item/enclosure

File download URL (@url), size (@length) and mime type (@type).

rss/channel/item/psc:chapters

Podlove Simple Chapters, version 1.1 and 1.2.

rss/channel/item/psc:chapters/psc:chapter

Chapter entry (@start, @title, @href and @image).

Atom

For Atom feeds, podcastparser will handle the following elements and attributes:

atom:feed

Podcast.

atom:feed/atom:title

Podcast title (whitespace is squashed).

atom:feed/atom:subtitle

Podcast description (whitespace is squashed).

atom:feed/atom:icon

Podcast cover art.

atom:feed/atom:link@href

Podcast website.

atom:feed/atom:entry

Episode.

atom:feed/atom:entry/atom:id

Episode unique identifier (GUID), mandatory.

atom:feed/atom:entry/atom:title

Episode title (whitespace is squashed).

atom:feed/atom:entry/atom:link@rel=enclosure

File download URL (@href), size (@length) and mime type (@type).

atom:feed/atom:entry/atom:link@rel=(self|alternate)

Episode website.

atom:feed/atom:entry/atom:link@rel=payment

Episode payment URL (e.g. Flattr).

atom:feed/atom:entry/atom:content

Episode description (in HTML or plaintext).

atom:feed/atom:entry/atom:published

Episode publication date.

atom:feed/atom:entry/psc:chapters

Podlove Simple Chapters, version 1.1 and 1.2.

atom:feed/atom:entry/psc:chapters/psc:chapter

Chapter entry (@start, @title, @href and @image).

The podcastparser module

Simplified, fast RSS parser

exception podcastparser.FeedParseError(msg, exception, locator)

Exception raised when asked to parse an invalid feed

This exception allows users of this library to catch exceptions without having to import the XML parsing library themselves.

class podcastparser.PodcastHandler(url, max_episodes)
characters(chars)

Receive notification of character data.

The Parser will call this method to report each chunk of character data. SAX parsers may return all contiguous character data in a single chunk, or they may split it into several chunks; however, all of the characters in any single event must come from the same external entity so that the Locator provides useful information.

endElement(name)

Signals the end of an element in non-namespace mode.

The name parameter contains the name of the element type, just as with the startElement event.

startElement(name, attrs)

Signals the start of an element in non-namespace mode.

The name parameter contains the raw XML 1.0 name of the element type as a string and the attrs parameter holds an instance of the Attributes class containing the attributes of the element.

class podcastparser.RSSItemDescription

RSS 2.0 almost encourages to put html content in item/description but content:encoded is the better source of html content and itunes:summary is known to contain the short textual description of the item. So use a heuristic to attribute text to either description or description_html, without overriding existing values.

podcastparser.file_basename_no_extension(filename)

Returns filename without extension

>>> file_basename_no_extension('/home/me/file.txt')
'file'
>>> file_basename_no_extension('file')
'file'
podcastparser.is_html(text)

Heuristically tell if text is HTML

By looking for an open tag (more or less:) >>> is_html(‘<h1>HELLO</h1>’) True >>> is_html(‘a < b < c’) False

podcastparser.normalize_feed_url(url)

Normalize and convert a URL. If the URL cannot be converted (invalid or unknown scheme), None is returned.

This will also normalize feed:// and itpc:// to http://.

>>> normalize_feed_url('itpc://example.org/podcast.rss')
'http://example.org/podcast.rss'

If no URL scheme is defined (e.g. “curry.com”), we will simply assume the user intends to add a http:// feed.

>>> normalize_feed_url('curry.com')
'http://curry.com/'

It will also take care of converting the domain name to all-lowercase (because domains are not case sensitive):

>>> normalize_feed_url('http://Example.COM/')
'http://example.com/'

Some other minimalistic changes are also taken care of, e.g. a ? with an empty query is removed:

>>> normalize_feed_url('http://example.org/test?')
'http://example.org/test'

Leading and trailing whitespace is removed

>>> normalize_feed_url(' http://example.com/podcast.rss ')
'http://example.com/podcast.rss'

Incomplete (too short) URLs are not accepted

>>> normalize_feed_url('http://') is None
True

Unknown protocols are not accepted

>>> normalize_feed_url('gopher://gopher.hprc.utoronto.ca/file.txt') is None
True
podcastparser.parse(url, stream, max_episodes=0)

Parse a podcast feed from the given URL and stream

Parameters
  • url – the URL of the feed. Will be used to resolve relative links

  • stream – file-like object containing the feed content

  • max_episodes – maximum number of episodes to return. 0 (default) means no limit

Returns

a dict with the parsed contents of the feed

podcastparser.parse_length(text)

Parses a file length

>>> parse_length(None)
-1
>>> parse_length('0')
-1
>>> parse_length('unknown')
-1
>>> parse_length('100')
100
podcastparser.parse_pubdate(text)

Parse a date string into a Unix timestamp

>>> parse_pubdate('Fri, 21 Nov 1997 09:55:06 -0600')
880127706
>>> parse_pubdate('2003-12-13T00:00:00+02:00')
1071266400
>>> parse_pubdate('2003-12-13T18:30:02Z')
1071340202
>>> parse_pubdate('Mon, 02 May 1960 09:05:01 +0100')
-305049299
>>> parse_pubdate('')
0
>>> parse_pubdate('unknown')
0
podcastparser.parse_time(value)

Parse a time string into seconds

See RFC2326, 3.6 “Normal Play Time” (HH:MM:SS.FRACT)

>>> parse_time('0')
0
>>> parse_time('128')
128
>>> parse_time('00:00')
0
>>> parse_time('00:00:00')
0
>>> parse_time('00:20')
20
>>> parse_time('00:00:20')
20
>>> parse_time('01:00:00')
3600
>>> parse_time(' 03:02:01')
10921
>>> parse_time('61:08')
3668
>>> parse_time('25:03:30 ')
90210
>>> parse_time('25:3:30')
90210
>>> parse_time('61.08')
61
>>> parse_time('01:02:03.500')
3723
>>> parse_time(' ')
0
podcastparser.parse_type(text)

“normalize” a mime type

>>> parse_type('text/plain')
'text/plain'
>>> parse_type('text')
'application/octet-stream'
>>> parse_type('')
'application/octet-stream'
>>> parse_type(None)
'application/octet-stream'
podcastparser.remove_html_tags(html)

Remove HTML tags from a string and replace numeric and named entities with the corresponding character, so the HTML text can be displayed in a simple text view.

podcastparser.squash_whitespace(text)

Combine multiple whitespaces into one, trim trailing/leading spaces

>>> squash_whitespace(' some           text  with a    lot of   spaces ')
'some text with a lot of spaces'

Unsupported Namespaces

This is a list of podcast-related XML namespaces that are not yet supported by podcastparser, but might be in the future.

Chapter Marks

  • rawvoice RSS: Rating, Frequency, Poster, WebM, MP4, Metamark (kind of chapter-like markers)

  • IGOR: Chapter Marks

Others

  • libSYN RSS Extensions: contactPhone, contactEmail, contactTwitter, contactWebsite, wallpaper, pdf, background

  • Comment API: Comments to a given item (readable via RSS)

  • MVCB: Error Reports To Field (usually a mailto: link)

  • Syndication Module: Update period, frequency and base (for skipping updates)

  • Creative Commons RSS: Creative commons license for the content

  • Pheedo: Original link to website and original link to enclosure (without going through pheedo redirect)

  • WGS84: Geo-Coordinates per item

  • Conversations Network: Intro duration in milliseconds (for skipping the intro), ratings

  • purl DC Elements: dc:creator (author / creator of the podcast, possibly with e-mail address)

  • Tristana: tristana:self (canonical URL to feed)

  • Blip: Show name, show page, picture, username, language, rating, thumbnail_src, license

Indices and tables