Category Archives: Too Good To

Too good to #0002

Show and update the comment in an SSH private key

ssh-keygen -l -f <keyfile> # show
ssh-keygen -c -f <keyfile> # change interactively
ssh-keygen -c -C <newcomment> -f <keyfile> # change and provide new

ssh-agent in Gitlab CI/CD

  • Define SSH_KEY as a “file” in Gitlab CI/CD variables and SSH_PASSPHRASE as a regular variable
  • If libcrypto errors on execution, make sure SSH_KEY has an additional line ending at the end
before_script:
  - DEBIAN_FRONTEND=noninteractive apt-get update -y
  - DEBIAN_FRONTEND=noninteractive apt-get install -y openssh-client

sftp_to_somewhere:
  stage: deploy
  script:
    - chmod 600 "$SSH_KEY"
    - eval $(ssh-agent)
    - ssh-add "$SSH_KEY" <<< "$SSH_PASSPHRASE"
    - ssh-add -l

Urlwatch, but with a local pop-up window on Linux, no additional infrastructure

Systemd user service:

# ~/.config/systemd/user/urlwatch-to-zenity.service
[Unit]
Description=urlwatch to zenity (service)

[Service]
Type=oneshot
ExecCondition=sh -c 'nmcli net co | grep full'
ExecCondition=sh -c 'urlwatch > %h/.cache/urlwatch.out'
ExecCondition=sh -c 'test -s %h/.cache/urlwatch.out'
ExecStart=sh -c 'zenity --title Urlwatch --text-info --width=600 --height=400 --filename=%h/.cache/urlwatch.out'

[Install]
WantedBy=default.target

Systemd timer:

# ~/.config/systemd/user/urlwatch-to-zenity.timer
[Unit]
Description=urlwatch to zenity (timer)

[Timer]
OnStartupSec=1h
OnUnitInactiveSec=2h

[Install]
WantedBy=default.target

cookiecount – Load a page and show the cookies it sets

$ ./cookiecount https://example.com
0 cookies received.

ps1_anon.bash – anonymize bash prompt, for screenshots and pastes

# Anonymize bash prompt for screenshots and pastes
# Source from or add to ~/.bashrc
function ps1_anon (){
	if [[ -v SAVED_PS1 ]] 
	then
		PS1="${SAVED_PS1}" 
		unset SAVED_PS1 
	else
		SAVED_PS1="${PS1}" 
		PS1='\$ '
	fi
}

Example:

[martin@idefix ~/devel/cookiecount(main=)]$ ps1_anon
$ ./cookiecount https://reddit.com --json | jq .cookiecount
7
$ ps1_anon
[martin@idefix ~/devel/cookiecount(main=)]$

Too good to #0001

Set X11 keyboard layout manually and temporarily (e.g. in i3 if I need to test exotic window managers for my users)

setxkbmap -layout us,us -variant altgr-intl -option caps:none

Speaking of which, set keyboard layout permanently in Gnome

gsettings set org.gnome.desktop.input-sources sources "[('xkb', 'us+altgr-intl')]"

Check if Gnome Screensaver is active (I use this for automated time tracking)

busctl --user call org.gnome.ScreenSaver /org/gnome/ScreenSaver org.gnome.ScreenSaver GetActive


Urlwatch for a new package version in an APT repository

After a long wait, I was finally able to find another use for my awful Perl one-liner from 2019 that pivots a Debian Packages.gz into a space-separated table!

---
name: "Pop!OS Firefox package"
command: curl -s http://apt.pop-os.org/release/dists/jammy/main/binary-amd64/Packages.gz |
  gzip -dc | perl -ane 'if($F[0]=~/^Package:/){$p=$F[1]};if($F[0]=~/^Version:/){$v=$F[1];print"$p $v\n";}' |
  grep '^firefox '
diff_filter:
  - grep: '^[+-][^+-]'
---