Title: Simple scripts I made over time | |
Author: Solène | |
Date: 19 July 2021 | |
Tags: openbsd scripts shell | |
Description: | |
# Introduction | |
I wanted to share a few scripts of mine for some time, here they are! | |
# Scripts | |
Over time I'm writing a few scripts to help me in some tasks, they are | |
often associated to a key binding or at least in my ~/bin/ directory | |
that I add to my $PATH. | |
## Screenshot of a region and upload | |
When I want to share something displayed on my screen, I use my simple | |
"screen_up.sh" script (super+r) that will do the following: | |
* use scrot and let me select an area on the screen | |
* convert the file in jpg but also png compression using pngquant and | |
pick the smallest file | |
* upload the file to my remote server in a directory where files older | |
than 3 days are cleaned (using find -ctime -type f -delete) | |
* put the link in the clipboard and show a notification | |
This simple script has been improved a lot over time like getting a | |
feedback of the result or picking the smallest file from various | |
combinations. | |
```script shell requiring scrot, pngquant, ImageMagick and notify-send | |
#!/bin/sh | |
test -f /tmp/capture.png && rm /tmp/capture.png | |
scrot -s /tmp/capture.png | |
pngquant -f /tmp/capture.png | |
convert /tmp/capture-fs8.png /tmp/capture.jpg | |
FILE=$(ls -1Sr /tmp/capture* | head -n 1) | |
EXTENSION=${FILE##*.} | |
MD5=$(md5 -b "$FILE" | awk '{ print $4 }' | tr -d '/+=' ) | |
ls -l $MD5 | |
scp $FILE perso.pw:/var/www/htdocs/solene/i/${MD5}.${EXTENSION} | |
URL="https://perso.pw/i/${MD5}.${EXTENSION}" | |
echo "$URL" | xclip -selection clipboard | |
notify-send -u low $URL | |
``` | |
## Uploading a file temporarily | |
Second most used script of mine is a uploading file utility. It will | |
rename a file using the content md5 hash but keeping the extension and | |
will upload it in a directory on my server where it will be deleted | |
after a few days from a crontab. Once the transfer is finished, I get | |
a notification and the url in my clipboard. | |
```script shell | |
#!/bin/sh | |
FILE="$1" | |
if [ -z "$1" ] | |
then | |
echo "usage: [file]" | |
exit 1 | |
fi | |
MD5=$(md5 -b "$1" | awk '{ print $NF }' | tr -d '/+=' ) | |
NAME=${MD5}.${FILE##*.} | |
scp "$FILE" perso.pw:/var/www/htdocs/solene/f/${NAME} | |
URL="https://perso.pw/f/${NAME}" | |
echo -n "$URL" | xclip -selection clipboard | |
notify-send -u low "$URL" | |
``` | |
## Sharing some text or code snippets | |
While I can easily transfer files, sometimes I need to share a snippet | |
of code or a whole file but I want to ease the reader work and display | |
the content in an html page instead of sharing an extension file that | |
will be downloaded. I don't put those files in a cleaned directory and | |
I require a name to give some clues about the content to potential | |
readers. The remote directory contains a highlight.js library used to | |
use syntactic coloration, hence I pass the text language to use the | |
coloration. | |
``` | |
#!/bin/sh | |
if [ "$#" -eq 0 ] | |
then | |
echo "usage: language [name] [path]" | |
exit 1 | |
fi | |
cat > /tmp/paste_upload <<EOF | |
<html> | |
<head> | |
<meta http-equiv="Content-type" content="text/html; charset=utf-8" /> | |
</head> | |
<body> | |
<link rel="stylesheet" href="default.min.css"> | |
<script src="highlight.min.js"></script> | |
<script>hljs.initHighlightingOnLoad();</script> | |
<pre><code class="$1"> | |
EOF | |
# ugly but it works | |
cat /tmp/paste_upload | tr -d '\n' > /tmp/paste_upload_tmp | |
mv /tmp/paste_upload_tmp /tmp/paste_upload | |
if [ -f "$3" ] | |
then | |
cat "$3" | sed 's/</\</g' | sed 's/>/\>/g' >> /tmp/paste_upload | |
else | |
xclip -o | sed 's/</\</g' | sed 's/>/\>/g' >> /tmp/paste_upload | |
fi | |
cat >> /tmp/paste_upload <<EOF | |
</code></pre> </body> </html> | |
EOF | |
if [ -n "$2" ] | |
then | |
NAME="$2" | |
else | |
NAME=temp | |
fi | |
FILE=$(date +%s)_${1}_${NAME}.html | |
scp /tmp/paste_upload perso.pw:/var/www/htdocs/solene/prog/${FILE} | |
echo -n "https://perso.pw/prog/${FILE}" | xclip -selection clipboard | |
notify-send -u low "https://perso.pw/prog/${FILE}" | |
``` | |
## Resize a picture | |
I never remember how to resize a picture so I made a one line script to | |
not have to remember about it, I could have used a shell function for | |
this kind of job. | |
```shell code | |
#!/bin/sh | |
if [ -z "$2" ] | |
then | |
PERCENT="40%" | |
else | |
PERCENT="$2" | |
fi | |
convert -resize "$PERCENT" "$1" "tn_${1}" | |
``` | |
# Latency meter using DNS | |
Because UDP requests are not reliable they make a good choice for | |
testing network access reliability and performance. I used this as | |
part of my stumpwm window manager bar to get the history of my internet | |
access quality while in a high speed train. | |
The output uses three characters to tell if it's under a threshold (it | |
works fine), between two threshold (not good quality) or higher than | |
the second one (meaning high latency) or even a network failure. | |
The default timeout is 1s, if it works, under 60ms you get a "_", | |
between 60ms and 150ms you get a "-" and beyond 150ms you get a "¯", | |
if the network is failure you see a "N". | |
For example, if your quality is getting worse until it breaks and then | |
works, it may look like this: _-¯¯NNNNN-____-_______ My LISP code | |
was taking care of accumulating the values and only retaining the n | |
values I wanted as history. | |
Why would you want to do that? Because I was bored in a train. But | |
also, when network is fine, it's time to sync mails or refresh that | |
failed web request to get an important documentation page. | |
```shell script | |
#!/bin/sh | |
dig perso.pw @9.9.9.9 +timeout=1 | tee /tmp/latencecheck | |
if [ $? -eq 0 ] | |
then | |
time=$(awk '/Query time/{ | |
if($4 < 60) { print "_";} | |
if($4 >= 60 && $4 <= 150) { print "-"; } | |
if($4 > 150) { print "¯"; } | |
}' /tmp/latencecheck) | |
echo $time | tee /tmp/latenceresult | |
else | |
echo "N" | tee /tmp/latenceresult | |
exit 1 | |
fi | |
``` | |
# Conclusion | |
Those scripts are part of my habits, I'm a bit lost when I don't have | |
them because I always feel they are available at hand. While they | |
don't bring much benefits, it's quality of life and it's fun to hack on | |
small easy pieces of programs to achieve a simple purpose. I'm glad to | |
share those. |