With a free (as in beer) service like uptimerobot, it’s possible to check if some websites are up or down. But sometimes it can be useful to check if some websites on the internal network are up or down, like for example in my case:

• my smart thermostat
• my jukebox
• …

Let’s write something in the Go programming language.

upck

upck is a little program written in go to check if a website is up or down. If a site is down or back up, it can send a warning (for example: by email).

When upck starts, it reads the file upck.cfg.

Syntax of upck.cfg:

# command to execute when site is down or back up 
# cmd = command 
# $url = replaced with url of site 
# $status = replaced with up or down 
cmd=echo "$url is $status." | mutt -s "$url is $status." jan.wagemakers@gmail.com 

# url's to check : should start with http 
https://www.janwagemakers.be 
http://janw.mooo.com:18452 
http://janw.mooo.com:24388 
http://janwagemakers.sdfeu.org/

Source is available at gitlab.

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