Charly's Column – rss2email

RSS feeds are still an essential part of my daily information refueling plan. I sort my feeds in Miniflux, a web-based RSS aggregator, which I wrote about in this column back in 2014 [1]. I am happy to say that Miniflux is still being actively developed.

I have a very small number of RSS feeds emailed to me directly. These are feeds that warn me of acute security problems. By having them delivered directly to my inbox, I can avoid the risk of missing an important article – Miniflux can handle between 200 and 250 feeds, most of which I just skim.

I use rss2email – a very logical choice of name – to email me the feeds. It can be found in the package sources of almost all the popular distributions. On Ubuntu, for example, I installed it with the following call:

$ sudo apt install rss2email

Before using rss2email for the first time, you have to create a configuration file; the approach is very clear-cut. If there is no folder named .config/ in your home directory, you have to create one and cd to it:

$ cd
$ mkdir .config
$ cd .config/

When you get there, use the editor of your choice to create the rss2email.cfg configuration file with the content from Listing 1; the force-from = True entry is of special importance here. Normally, rss2email would use a sender address from the RSS feed if it found one there. However, on many mail systems, this leads to the spam filter rightly becoming suspicious. The force-from = True entry now causes rss2email to always use the address stored in the from line. Whether you set html-mail to True or False is a matter of taste.

[DEFAULT]
from = rss@mydomain.com
force-from = True
html-mail = False
to = charly@mydomain.com

Now it's time to choose one or more RSS feeds that you want rss2email to check out regularly. The syntax for this is:

r2e add <title> <URL>

For the DFN Certificate RSS feed, which informs admins of current security problems, look at the first line in Listing 2. Whether the add action worked can be verified using r2e list (line 2). It worked in my example.

01 $ r2e add DFNCert https://adv-archiv.dfn-cert.de/rss/latest
02 $ r2e list
03 0: [*] DFNCERT (https://adv-archiv.dfn-cert.de/rss/latest -> charly@mydomain.com)

The r2e run command traverses the feeds and dispatches the emails. Now all I need to do is write a crontab entry to run the command at specified intervals (e.g., every 30 minutes). To do so, I type crontab -e and add the crontab line from Listing 3.

*/30 * * * * /usr/bin/r2e run > /dev/null 2>&1

Sure enough, the first messages start to slowly arrive in my mailbox (Figure 1). The important thing here is to be careful about the rss2email feeds you choose; otherwise you might flood your inbox – just staying with Miniflux would be preferable to that.

Figure 1: Charly uses rss2email to deliver information from RSS feeds about acute vulnerabilities directly to his mailbox.