shatom

a feed generator in (mostly) POSIX shell

Because of a post in the Gemini mailing list bemoaning the inability to generate Atom feeds using bare-bones computers, I present shatom, a shell program that purports to do just that.

Now with RSS 2.0 abilities baked in!

It has minimal dependencies (see DEPENDENCIES, below), and is completely modifiable by the user with the config file (see CONFIG, below).

And it’s licensed permissively. What more could you want!?

DEPENDENCIES

POSIX shell and tools
stat(1) - optional, but nice to have for figuring out mtime

CONFIG

All of the functions and variables defined in shatom can be overwritten by a config file, by default shatom.conf.sh in the current directory. As may be obvious from the file’s extension, it’s a shell script, so you can redefine (and in fact, should redefine) all the variables and functions in shatom to suit your needs.

Here’s a convenient list:

Variables

FEED_TITLE - the title of your feed
FEED_AUTHOR - the author of your feed (you!)
FEED_SUBTITLE - the subtitle of your feed
FEED_URL - the URL where your feed can be accessed
SITE_URL - the base URL of your site
FEED_ID - the Atom ID of the feed (default: SITE_URL)
FEED_COPYRIGHT - the copyright information of your feed
FEED_UPDATED - the date your feed was last updated, defaulting to the current time

Functions

File functions

recent_files - sort files recursively, in reverse

Item functions

These operate on items themselves, in the inner for loop of main. They’re all passed the path of the item. See the source for their default implementations.

skip_item - whether to skip an item (default: don’t). Return 0 to skip an item.
item_url - pull the URL out of an item
item_title - pull the title from an item
item_summary - pull the summary from an item
item_author - pull the author from an item
item_content - pull the content from an item
item_updated - pull the modification time from an item

Feed functions

These generate the actual feed bits. Should be pretty self-explanatory.

feed_header
feed_item
feed_footer

POSIX compliance

As it is written in this repo, shatom is 99% POSIX-compliant: of 176 source lines, only 2 require a non-POSIX tool, stat(1). Of course, you can change these functions to be whatever you like, so you don’t have to make it POSIX-compliant if you don’t want to. Go nuts!

Copyright

2020 Case Duckworth. Licensed under the Good Choices License. See COPYING for details.

Contributing

Feel free to send patches, complaints, and praise to my email.