FEED2EXEC(1) feed2exec FEED2EXEC(1)

feed2exec - The programmable feed reader

feed2exec {add,ls,rm,fetch,import,export}

This command will take a configured set of feeds and fire specific plugin for every new item found in the feed.

Show the version and exit.
choose specific log level [default: WARNING]
show what is happening (loglevel: VERBOSE)
show debugging information (loglevel: DEBUG)
send LEVEL logs to syslog
use a different configuration file
use a different database
Show this message and exit.



Simple run with no side effects:

feed2exec parse https://www.nasa.gov/rss/dyn/breaking_news.rss --output echo --args '{item.title}'


Saving feed items to a Maildir folder:

feed2exec add "NASA breaking news" https://www.nasa.gov/rss/dyn/breaking_news.rss --folder nasa
feed2exec fetch


This creates the equivalent of this configuration file in ~/.config/feed2exec.ini:

[DEFAULT]
output = feed2exec.plugins.maildir
mailbox = ~/Maildir
[NASA breaking news]
folder = nasa
url = https://www.nasa.gov/rss/dyn/breaking_news.rss


Send new feed items to Transmission:

feed2exec add "Example torrent list" http://example.com/torrents/feed --output transmission --folder /srv/incoming


Send new feed items to Mastodon, using the toot commandline client:

feed2exec add "My site" http://example.com/blog/feed --output exec --args 'toot post "{item.title} {item.link}"'


Send new feed items to Twitter, using the tweet commandline client from python-twitter:

feed2exec add "My site on twitter" http://example.com/blog/feed --output exec --args 'tweet "{item.title:.40s} {item.link:.100s}"'


Show feed contents:

feed2exec add "NASA breaking news" https://www.nasa.gov/rss/dyn/breaking_news.rss --output echo --args "{item.title} {item.link}"
feed2exec fetch


  • parse
  • fetch
  • add
  • ls
  • rm
  • import
  • export

Usage:

parse URL
    [--output PLUGIN [--args ARG [ARG [...]]]
    [--filter PLUGIN] [--filter_args ARG [ARG [...]]]
    [--mailbox PATH] [--folder PATH]


The parse command loads and parses a single feed, without touching the database. This is similar to calling add then fetch on a single feed, but the feed is not kept in the configuration. This is designed to make quick tests with a new feed. The arguments are the same as the add command.

Usage:

fetch [--parallel | -p | --jobs N | -j N] [--force | -f] [--pattern pattern]


The fetch command iterates through all the configured feeds or those matching the pattern substring if provided.

Options:

only fetch feeds matching name or URL
parse feeds in the background to improve performance
start N jobs in parallel, implies --parallel which defaults to the number of CPUs detected on the machine
skip reading and writing the cache and will consider all entries as new
tell output plugins plugins to simulate their actions



Usage:

add NAME URL
    [--output PLUGIN [--args ARG [ARG [...]]]
    [--filter PLUGIN] [--filter_args ARG [ARG [...]]]
    [--mailbox PATH] [--folder PATH]


The add command adds the given feed NAME that will be fetched from the provided URL.

Options:

use PLUGIN as an output module. defaults to maildir to store in a mailbox. use null or echo to just fetch the feed without doing anything. Modules are searched in the feed2exec.plugins package unless the name contains a dot in which case the whole Python search path is used.
pass arguments ARGS to the output plugin. supports interpolation of feed parameters using, for example {title}
filter feed items through the PLUGIN filter plugin
arguments passed to the filter plugin
folder to store email into, defaults to ~/Maildir.
subfolder to store the email into



Those parameters are documented more extensively in their equivalent settings in the configuration file, see below.

The ls command lists all configured feeds as JSON packets.

Usage:

rm NAME


Remove the feed named NAME from the configuration.

Usage:

import PATH


Import feeds from the file named PATH. The file is expected to have outline elements and only the title and xmlUrl elements are imported, as NAME and URL parameters, respectively.

Usage:

export PATH


Export feeds into the file named PATH. The file will use the feed NAME elements as title and the URL as xmlUrl.

The configuration file is loaded from (and written to, by add) ~/.config/feed2exec.ini or $XDG_CONFIG_HOME/feed2exec.ini. It can also be specified with the --config commandline parameter. This is an example configuration snippet:

[NASA breaking news]
url = https://www.nasa.gov/rss/dyn/breaking_news.rss
output = feed2exec.plugins.echo
args = {title} {link}


Naturally, those settings can be changed directly in the config file. Note that there is a [DEFAULT] section that can be used to apply settings to all feeds. For example, this will make all feeds store new items in a maildir subfolder:

[DEFAULT]
output = feed2exec.plugins.maildir
folder = feeds


This way individual feeds do not need to be individually configured.

NOTE:

feed2exec does not take care of adding the folder to “subscriptions” in the mailbox. it is assumed that folders are auto-susbcribed or the user ignores subscription. if that is a problem, you should subscribe to the folder by hand in your email client when you add a new config. you can also subscribe to a folder (say feeds above) directly using the doveadm mailbox subscribe feeds command in Dovecot, for example.


The following configuration parameters are supported:

Human readable name for the feed. Equivalent to the NAME argument in the add command.
Address to fetch the feed from. Can be HTTP or HTTPS, but also file:// resources for test purposes.
Output plugin to use. Equivalent to the --output option in the add command.
Arguments to pass to the output plugin. Equivalent to the --args option in the add command.
Filter plugin to use. Equivalent to the --filter option in the add command.
Store emails in that mailbox prefix. Defaults to ~/Maildir.
Subfolder to use when writing to a mailbox. By default, a slugified version of the feed name (where spaces and special character are replaced by -) is used. For example, the feed named “NASA breaking news” would be stored in ~/Maildir/nasa-breaking-news/. Note that the mailbox prefix is used only if the folder path is relative.
Skip to the latest feed items. The feed is still read and parsed, and new feed items are added to the database, but output plugins are never called.
Completely skip feed during fetch or parse. Similar to catchup, but doesn’t fetch the feed at all and doesn’t touch the cache.



Here is a more complete example configuration with all the settings used:

# this section will apply to all feeds
[DEFAULT]
# special folder location for maildir. I use this when I have multiple
# accounts synchronized with Offlineimap
mailbox = ~/Maildir/Remote/
# a feed to store NASA breaking news entry in a "nasa" subfolder
# this also demonstrates the droptitle filter
[NASA breaking news]
url = https://www.nasa.gov/rss/dyn/breaking_news.rss
folder = nasa
filter = feed2exec.plugins.droptitle
filter_args = trump
# some maildir storage require dots to get subfolders. for example,
# this will store messages in INBOX/feeds/images/ on Dovecot
[NASA image of the day]
url = https://www.nasa.gov/rss/dyn/lg_image_of_the_day.rss
folder = .feeds.images
# same feed, but save to wayback machine
[NASA IOTD wayback]
url = https://www.nasa.gov/rss/dyn/lg_image_of_the_day.rss
output = feed2exec.plugins.wayback
# this demonstrates the emptysummary filter, which fixes GitHub feeds
# that lack a proper summary
[restic]
url = https://github.com/restic/restic/tags.atom
filter = feed2exec.plugins.emptysummary
# saving to a mbox folder, one file per feed instead of one file per item
[International Space Station Reports]
url = http://blogs.nasa.gov/stationreport/feed/
mailbox = ~/Mail/
folder = stationreport.mbx
# simple generic exec call example: check for broken links using linkchecker
[NASA linkchecker]
url = https://www.nasa.gov/rss/dyn/breaking_news.rss
output = feed2exec.plugins.exec
args = linkchecker --check-extern --no-robots --recursion-level 1 --quiet '{item.link}'
# same, but with a Ikiwiki RSS feed, which needs fixing
[Ikiwiki linkchecker]
url = http://ikiwiki.info/recentchanges/index.rss
output = feed2exec.plugins.exec
filter = feed2exec.plugins.ikiwiki_recentchanges
args = linkchecker --check-extern --no-robots --recursion-level 1 --quiet '{item.link}'
# retweet hurricane news
[NASA Hurricane breaking news]
url = https://www.nasa.gov/rss/dyn/hurricaneupdate.rss
output = feed2exec.plugins.exec
args = tweet "{item.title:.40s} {item.link:.100s}"
# same, but on the mastodon network
#
# we can have multiple entries with the same URL without problems, as
# long as the feed name is different. it does mean that the feed will
# be fetched and parsed multiple times, unfortunately.
#
# this could be improved to include the '{item.summary}' and extra markup,
# for example.
[NASA Hurricane breaking news - Mastodon]
url = https://www.nasa.gov/rss/dyn/hurricaneupdate.rss
output = feed2exec.plugins.exec
# unfortunately, this will noisily report the URL of the posted link,
# which you may not want. to avoid that, encourage upstream to do the
# right thing: https://github.com/ihabunek/toot/issues/46 ... or use
# another tool listed here:
# https://github.com/tootsuite/documentation/blob/master/Using-Mastodon/Apps.md
args = toot post "{item.title} {item.link}"
# output is disabled here. feed will be fetched and parsed, but no
# toot will be sent
catchup = True
# same, but on the Pump.io network
[NASA Hurricane breaking news - Pump]
url = https://www.nasa.gov/rss/dyn/hurricaneupdate.rss
output = feed2exec.plugins.exec
args = p post note "{item.title} {item.link}"
# crude podcast client
[NASA What up?]
url = https://www.nasa.gov/rss/dyn/whats_up.rss
output = feed2exec.plugins.exec
# XXX: this doesn't handle errors properly: if there is a feed without
# enclosures, the whole thing will crash.
args = wget -P /srv/podcasts/nasa/ "{item.enclosures[0].href}"
# feed is paused here. feed will not be fetched and parsed at all and
# no post will be sent.
pause = True
# download torrents linked from a RSS feed
[torrents]
url = http://example.com/torrents.rss
output = feed2exec.plugins.exec
args = transmission-remote -a '{item.link}' -w '/srv/incoming'
# same thing with an actual plugin
[torrents]
url = http://example.com/torrents.rss
output = feed2exec.plugins.transmission
args = seedbox.example.com
folder = /srv/incoming


The feeds cache is stored in a feed2exec.db file. It is a SQLite database and can be inspected using standard sqlite tools. It is used to keep track of which feed and items have been processed. To clear the cache, you can simply remove the file, which will make the program process all feeds items from scratch again. In this case, you should use the --catchup argument to avoid duplicate processing. You can also use the null output plugin to the same effect.

Feed support is only as good as feedparser library which isn’t as solid as I expected. In particular, I had issues with feeds without dates and without guid.



Unit test coverage is incomplete, but still pretty decent, above 90%.

The exec plugin itself is not well tested and may have serious security issues.

API, commandline interface, configuration file syntax and database format can be changed until the 1.0 release is published, at which point normal Semantic Versioning semantics apply.

The program is written mainly targeting Python 3.5 and 3.7, but should support later releases as well. See the setup.py classification for an authoritative reference. Python 2.7 is not supported anymore.

The SQL storage layer is badly written and is known to trigger locking issues with SQLite when doing multiprocessing. The global LOCK object could be used to work around this issue but that could mean pretty bad coupling. A good inspiration may be the beets story about this problem. And of course, another alternative would be to considering something like SQLalchemy instead of rolling our own ORM. There has, however, been some improvements to the locking recently, although that has been done with thread instead of process-specific locks.

Older feed items are not purged from the database when they disappear from the feed, which may lead to database bloat in the long term. Similarly, there is no way for plugins to remove old entry that expire from the feed.

feed2exec-plugins(1), feed2imap(1), rss2email(1)

Antoine Beaupré

Copyright (C) 2016-2019 Antoine Beaupré

January 17, 2024 0.20.0