December 2017 - Python in the jungle

Truncate large files in linux

Better late than never

Truncate file into Mb’s

$ sudo truncate -s 10M filename.log

Truncate file into Gb’s

$ sudo truncate -s 1G filename.log

Minify html output with simple php function

It’s always a pleasure to have html tags tidy and attached to one another. especially if these html tags are yours in your website. To have this we can do with a simple php function. Place the code below at the top of header php page or index page.

<?php
function sanitize_output($buffer) {
  $search = array(
    '/\>[^\S ]+/s',
    '/[^\S ]+\</s',
    '/(\s)+/s',
    '/<!--(.|\s)*?-->/'
  );
  $replace = array(
    '>',
    '<',
    '\',
    ''
  );
  $buffer = preg_replace($search, $replace, $buffer);
  return $buffer;
}
ob_start("sanitize_output");
?>

Create module in puppet

$ mkdir ~/mymodules
$ cd ~/mymodules
~/mymodules~$ puppet module generate pulpn-test --skip-interview

$ puppet module install puppetlabs-stdlib

$ puppet module build ~/mymodules/test

How to download and convert video from youtube to MP3 in terminal

So, I needed to download songs from youtube but not as a video but only audio. Then I went to this website to convert these video as usual. The website that I used to convert video from youtube was popped out ads that I didn’t like. I started to thinking why the hell that I need those websites anyway? just use the terminal instead.

$ youtube-dl --extract-audio --audio-format mp3 <youtube-url>

Setup uWSGI and Emperor on Centos 6.xx

uWSGI is driving me crazy when install it, every single time. I’m using Centos 6.9 to setup my python app.

This one is for setup uWSGI and make sure you already installed Python2.7 on your machine:

$ wget https://bootstrap.pypa.io/get-pip.py
$ which python2.7
$ sudo /usr/local/bin/python2.7 get-pip.py
$ which pip2.7
$ sudo /usr/local/bin/pip2.7 install uWSGI
$ which uwsgi
$ uwsgi --version

Test your app with uWSGI manually:

$ sudo /usr/local/bin/uwsgi --ini /dir/to/app/uwsgi.ini

Setup vassels from uwsgi ini file

$ sudo mkdir -p /etc/uwsgi/vassels
$ sudo ln -s /dir/to/app/uwsgi.ini /etc/uwsgi/vassels/appname.ini

Create emperor to make uWSGI as a service:

$ sudo vim /etc/init.d/emperor

#!/bin/sh
# chkconfig: 2345 99 10
# Description: Starts and stops the emperor-uwsgi
# See how we were called.

RUNEMPEROR="/usr/local/bin/uwsgi --emperor=/etc/uwsgi/vassels"

PIDFILE=/var/run/emperor-uwsgi.pid
LOGFILE=/var/log/uwsgi/emperor.log

start() {
  if [ -f /var/run/$PIDNAME ] && kill -0 $(cat /var/run/$PIDNAME); then
    echo 'Service emperor-uwsgi already running' >&2
    return 1
  fi
  echo 'Starting Emperor...' >&2
  local CMD="$RUNEMPEROR &> \"$LOGFILE\" & echo $!"
  su -c "$CMD" > "$PIDFILE"
  echo 'Service started' >&2
}

stop() {
  if [ ! -f "$PIDFILE" ] || ! kill -0 $(cat "$PIDFILE"); then
    echo 'Service emperor-uwsgi not running' >&2
    return 1
  fi
  echo 'Stopping emperor-uwsgi' >&2
  kill -7 $(cat "$PIDFILE") && rm -f "$PIDFILE"
  echo 'Service stopped' >&2
}

status() {
    if [ ! -f "$PIDFILE" ]; then
	echo "Emperor is not running." >&2
	return 1
    else
    	echo "Emperor (pid  `cat ${PIDFILE}`) is running..."
    	ps -ef |grep `cat $PIDFILE`| grep -v grep
    fi
}

case "$1" in
start)
      start
      ;;
stop)
      stop
      ;;
status)
      status
      ;;
restart)
      stop
      start
      ;;
*)
    echo "Usage: emperor {start|stop|restart}"
    exit 1
esac

$ sudo chmod +x /etc/init.d/emperor
$ sudo /etc/init.d/emperor start
$ sudo chkconfig emperor on

Check your app if it’s already running:

$ sudo ps -ef | grep uwsgi