Working with feedsSpecialised needseditdelete

Libraries for generating and working with Atom/RSS feeds (Atom is a newer format, but RSS has wider adoption – most feed readers support both).

edit description

or press Ctrl+Enter to save

feed (Hackage)

other

Summary

A big and fairly complete (but messy) library for generating, parsing, and validating Atom/RSS feeds.

Summary

Pros

The only library here that can parse feeds in addition to generating them.
Supports the most number of formats (Atom, RSS 2.x, and even old RSS 1.0).

press Ctrl+Enter or Enter to add

edit off

Cons

Uses String instead of Text.
Kinda complicated (and you would have to take several looks at others' feeds and at the documentation for Atom/RSS formats, since the library itself doesn't have much documentation).

press Ctrl+Enter or Enter to add

edit off

Ecosystem

or press Ctrl+Enter to save

Notes

expand notes

collapse notesedit notes

Imports

For Atom feeds:

import qualified Text.Feed.Types as Feed
import qualified Text.Feed.Util  as Feed

import qualified Text.Atom.Feed        as Atom
import qualified Text.Atom.Feed.Export as Atom

-- from the “xml” package
import qualified Text.XML.Light.Output as XML

Creating an Atom feed

There are several types that you would need:

Feed
Entry (feed entry)
EntryContent (can be e.g. TextContent, HTMLContent, or a few others)
TextContent is unrelated to EntryContent, and can be a TextString or a HTMLString
Person (author of an entry)
Link

Each of these (apart from EntryContent and TextContent) is a record with lots of fields. You would almost never need all of those fields, so there are some helper functions available that make initialising them easier. For instance, to create a Link, use nullLink:

-- URI = String
nullLink :: URI -> Link

And then you can customise some of the fields:

nullLink "http://foo.bar" {
  linkTitle = Just "Foo Bar" }

Same with nullEntry and nullFeed; a complete example can be found here. Note that:

The example uses Strings as dates. If you want to convert UTCTime to the string format expected by the library, use toFeedDateStringUTC AtomKind (from Text.Feed.Util and Text.Feed.Types respectively).
The newest entry should be the 1st in the list.
The feed ID (i.e. the 1st parameter to nullFeed) doesn't have to be a link – for instance, for Github feeds it's something like
```
tag:github.com,2008:/bergmark/feed/commits/master
```
Entry IDs, contrary to what the example says, don't have to be links either.