Electronic requests approval workflow with other features (PWA)

This app enables an electronic requests approval workflow. Other main functions:

• information about the amount of time off left
• employee listing for a manager that gives details like eg. a contract end date, a possibility to quickly check if an empoyee should be present at work today
• e-mail notifications to a manager that a request's been sent
• push notifications about leave requests status changes
• pdf report generator about days off, sick leaves
• sick leaves registration page
• optional direct sick leaves data download from ZUS
• possibility to download documents (like regulations, private insurance contract rules etc.) for employees

Django 3.2. used Python 3.6 or later is required. Settings are configured to work with MySQL database ( installation of mysqlclient driver is needed ). Or with Postgres (DEVIL is True) (installation of psycopg2 driver is needed)

Configuration on Ubuntu 18.04 server with NGINX, Gunicorn & Supervisor

sudo apt-get update && sudo apt-get upgrade
pip3 install pip --upgrade
sudo apt install git nginx supervisor

export PYTHONIOENCODING="UTF-8"

Create folders, virtual environment and copy the source code

mkdir /webapps
cd webapps

sudo apt-get python3-venv
python3 -m venv wnioskivenv

cd wnioskivenv
git clone https://github.com/treflina/wnioski.git

source bin/activate

cd wnioski
pip3 install -r requirements.txt
sudo apt-get install gettext
sudo apt-get install libmagic1

In case there's a problem with installing Pillow:

apt install libjpeg8-dev zlib1g-dev libtiff-dev libfreetype6 libfreetype6-dev libwebp-dev libopenjp2-7-dev libopenjp2-7-dev -y

pip3 install pillow --global-option="build_ext" --global-option="--enable-zlib" --global-option="--enable-jpeg" --global-option="--enable-tiff" --global-option="--enable-freetype" --global-option="--enable-webp" --global-option="--enable-webpmux" --global-option="--enable-jpeg2000"

Place a file called secret.json in this base directory. The content should look this way:

{
    "FILENAME": "secret.json",
    "SECRET_KEY": "yoursecretkey",
    "DB_NAME": "yourdatabasename",
    "DB_USER": "databaseuser",
    "DB_PASSWORD": "databasepassword",
    "DB_HOST": "",
    "ALLOWED_HOSTS": ["localhost", "127.0.0.1", "other IP adresses", "domain"],
    "DEFAULT_FROM_EMAIL": "",
    "EMAIL_HOST": "",
    "EMAIL_HOST_USER": "",
    "EMAIL_HOST_PASSWORD": "",
    "EMAIL_PORT": "",
    "DEBUG": false,
    "VAPID_PUBLIC_KEY": "genaratedvapidpublicserverkeyforpushnotifications",
    "VAPID_PRIVATE_KEY": "genaratedvapidprivatekeyforpushnotifications",
    "ADMIN_EMAIL": "admin@example.com",
    "DEVIL": false
}

DEVIL set to true and passenger_wsgi.py file are used in case of mydevil.net hosting.

Optional configuration: direct sick leaves data download from polish ZUS

Place .env file in the root directory with the content below:

EZLA_URL=https://...      //url taken from zus docs
EZLA_SERVICE_USERNAME=username     //username taken from zusdocs
EZLA_SERVICE_PSWD=password   //password from zus docs
EZLA_SERVICE_IP=XXX.XXX.XX.XX  //IP adress of ZUS service
EZLA_LOGIN=user@example.com  //set in zus pue
EZLA_HASLO=strongpassword //set in zus pue
EZLA_NIP=1111111100   //employer's tax number
EZLA_EXTRACT_PSWD=passwordto_extract_data_from_reports //set in zus pue

More information: ZUS docs

Gunicorn

pip3 install gunicorn

Create a file called "gunicorn_start" in /webapps/wnioskivenv/bin:

#!/bin/bash

NAME="wnioski"                                  # Name of the application
DJANGODIR=/webapps/wnioskivenv/wnioski             # Django project directory
SOCKFILE=/webapps/wnioskivenv/run/gunicorn.sock  # we will communicte using this unix socket
USER=root                                        # the user to run as (it's not recommandable to have root as user)
GROUP=root                                     # the group to run as (it's not recommandable to have root as user)
NUM_WORKERS=3                                     # how many worker processes should Gunicorn spawn
DJANGO_SETTINGS_MODULE=wnioski.settings             # which settings file should Django use
DJANGO_WSGI_MODULE=wnioski.wsgi                     # WSGI module name

echo "Starting $NAME as `whoami`"

# Activate the virtual environment
cd $DJANGODIR
source ../bin/activate
export DJANGO_SETTINGS_MODULE=$DJANGO_SETTINGS_MODULE
export PYTHONPATH=$DJANGODIR:$PYTHONPATH

# Create the run directory if it doesn't exist
RUNDIR=$(dirname $SOCKFILE)
test -d $RUNDIR || mkdir -p $RUNDIR

# Start your Django Unicorn
# Programs meant to be run under supervisor should not daemonize themselves (do not use --daemon)
exec ../bin/gunicorn ${DJANGO_WSGI_MODULE}:application \
  --name $NAME \
  --workers $NUM_WORKERS \
  --user=$USER --group=$GROUP \
  --bind=unix:$SOCKFILE \
  --log-level=debug \
  --log-file=-

Add permissions

chmod u+x gunicorn_start

Check if it works

gunicorn_start

Supervisor

cd /etc/supervisor/conf.d/

Create a file called "wnioski.conf":

[program:wnioski]
command = /webapps/wnioskivenv/bin/gunicorn_start                    ; Command to start app
user = root                                                          ; User to run as
stdout_logfile = /webapps/wnioskivenv/logs/gunicorn_supervisor.log   ; Where to write log messages
redirect_stderr = true                                                ; Save stderr in the same log
environment=LANG=en_US.UTF-8,LC_ALL=en_US.UTF-8                       ; Set UTF-8 as default encoding

cd /webapps/wnioskivenv
mkdir logs
touch logs/gunicorn_supervisor.log

Check if supervisor works: supervisorctl reread correct response: "wnioski: available"
supervisorctl update
correct response: "wnioski: added process group"

NGINX

cd /etc/nginx/sites-available/

Create a file called "wnioski":

upstream wnioski_server {
  server unix:/webapps/wnioskivenv/run/gunicorn.sock fail_timeout=0;
}

server {

    listen   80;
    server_name  YOUR IP ADDRESS;

    access_log /webapps/wnioskivenv/logs/nginx-access.log;
    error_log /webapps/wnioskivenv/logs/nginx-error.log;

    location /static/ {
        alias   /webapps/wnioskivenv/wnioski/staticfiles/;
    }

    location /media/ {
        alias   /webapps/wnioskivenv/wnioski/media/;
    }

    location / {
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header Host $http_host;
        proxy_redirect off;

        if (!-f $request_filename) {
            proxy_pass http://wnioski_server;
            break;
        }
    }
}

cd
ln -s /etc/nginx/sites-available/wnioski /etc/nginx/sites-enabled/wnioski

service nginx restart

Check:

supervisorctl restart wnioski

Create a place for logs:

cd webapps/wnioskivenv/logs
touch nginx-access.log
touch nginx-error.log

Create staticfiles, make migrations to database, createsuperuser

cd webapps/wnioskivenv/wnioski

python3 manage.py collectstatic
python3 manage.py makemigrations
python3 manage.py migrate
python3 manage.py createsuperuser