Mess Feedback System using RFID

License

This Project is Licensed under the GNU GENERAL PUBLIC LICENSE Version 2

Instructions

1. Hardware used

   • Raspberry Pi 3
   • 16 GB SD Card
   • Power supply cable for Pi
   • Screen for Rpi(Setup steps given for multiple screens - check below)
   • MFRC522 RFID card reader
   • HDMI Display, Keyboard and Mouse (For initial setup)

2. Install Raspbian Stretch on the 16GB SD Card.

3. Open a terminal and run sudo raspi-config

   • Change Password to some strong password
   • Localisation Options
     • Change Timezone to "Asia/Kolkata"
     • Change Keyboard Layout to "Dell 101 Key PC". Language is English US. Set defaults for everything else.
     • Change Wifi Country to India
   • Interfacing Options
     • Enable SSH
     • Enable SPI
   • Advanced Options
     • Expand filesystem
   • Finish and Reboot

4. Setup Networking

   • Wifi - Just use the GUI to connect
   • Static IP for Ethernet Connection can be set in /etc/dhcpcd.conf
   • For the IP address, you will have to ask your local network admin.
   • Just for good measure, Reboot after these changes

5. Set up proxy

   • In /etc/apt/apt.conf
   • In ~/.bashrc
   • For information on how to set proxy in apt.conf and bashrc, you can look at https://medium.com/@krish.raghuram/setting-up-proxy-in-ubuntu-95058da0b2d4
   • Though the above post is for ubuntu, the changes to be made to apt.conf and bashrc files are exactly the same for raspbian as well.

6. SSH

   • Test SSH
   • Setup key based SSH
   • Disable password based SSH

7. Setup Firewall

   • sudo apt-get install ufw
   • Set default rule for incoming data to deny
   • Allow http, https, openssh, and port 8000
   • Enable ufw

8. Setup Date and Time Syncing

   • Raspberry Pi does not have an internal clock. Raspbian syncs time using NTP. But IITG firewall blocks this.
   • Thus, we are going to use a different method - htpdate and cron
     • Run sudo apt-get install htpdate
     • Run sudo crontab -e (If its the first time, you will be asked to choose a text editor. For beginners, nano is the easiest editor to use)
     • Add this at the bottom of the file * * * * * /usr/sbin/htpdate -s intranet.iitg.ernet.in
     • Save and Exit

9. Setting up Screen and MFRC522 Reader

   • git clone https://github.com/krishraghuram/mess
   • cd mess
   • git submodule init
   • git submodule update
   • cd mess-rpisetup
   • Checkout branch of the screen that you are using. Instructions are provided for Waveshare 3.5 Inch, Waveshare 7 Inch and Newhaven NHD-7.0-HDMI-N-RSXN-CTU Displays.
   • Follow the instructions in the "Todo" file
   • Complete it and Test it before continuing!!!
   • Also, quickstart to "git submodules" - https://git-scm.com/book/en/v2/Git-Tools-Submodules

10. Configure database settings for the feedback system

    • Firstly, let us understand the database architecture.
      • We will run one instance of the feedback system on a central server. This will NOT be used for feedback, but for HAB staff to access and update the system. This central server will also host the database that will be used by all feedback systems.
      • Each hostel's feedback system will connect to this central database. Thus, the user and feedback data across all hostels will always be consistent.
    • Instructions for central system
      • sudo apt-get install mariadb-server libmariadbclient-dev
      • sudo mysql -u root
        • CREATE DATABASE mess;
        • CREATE USER 'mess'@'localhost' IDENTIFIED BY 'mess';
        • GRANT ALL PRIVILEGES ON mess . * TO 'mess'@'localhost';
        • FLUSH PRIVILEGES;
    • Instructions for hostel systems
      • Open django's settings.py
      • In DATABASES variable, in 'HOST': 'localhost', replace 'localhost' with the IP adress of the central server.

11. Setup and test the django project

    • Go to the project folder
    • Setup current_hostel variable. This variable is used to ensure users can only give feedback at subscribed_hostel and not any other hostel.
      • We need to setup which hostel we are working on.
      • This is setup in rating/constants.py current_hostel
    • sudo -E -H pip install -r requirements.txt
    • Checkout the needed version(using git)
    • python manage.py makemigrations
    • python manage.py migrate
    • python manage.py createsuperuser
    • python manage.py runserver 0.0.0.0:8000
    • Go to a web browser and type '127.0.0.1:8000' and test if the website is working

12. Deploy using Gunicorn and Nginx. You can follow this link.
    The guide uses postgresql, but we plan to use mariadb - so make necessary changes.
    The guide also uses virtual environments, but we dont need to use virtual environment in production - so make necessary adjustments.

    • Run sudo apt-get install nginx
    • Run sudo -E -H pip install gunicorn
    • The django deployment checklist
      The following need to be set with appropriate values.
      • TIME_ZONE
      • STATIC_ROOT and STATIC_URL
      • SECRET_KEY
      • Ensure that database password is taken from environment variable, instead of passing it as cleartext in the settings file.
      • DEBUG
      • ALLOWED_HOSTS
      • LOGGING
      • MEDIA_ROOT and MEDIA_URL
    • Secret Key and Database Passwords should be taken from environment.
      However, gunicorn will not use the variables from bashrc(both user and root do not work) or /etc/environment
      So, to set env variables for gunicorn - Follow this link
      TL; DR instructions
      • Create a file in /home/pi/mess called django_environment_variables, and put the following contents.
        You might need to change the values.

       SECRET_KEY="alkvno39u109jgl1knfocyr9183ryo1hfo1c8n"
       DATABASE_PASSWORD="totallymypass"
      

      • Below, when we create gunicorn.service file, we will add a reference to /home/pi/mess/django_environment_variables
      • For running python manage.py <somecommand>, you need the SECRET_KEY and DATABASE_PASSWORD in the environment. The simplest way to do this is to add a export them from bashrc.
        • nano ~/.bashrc

         #Django
         export SECRET_KEY="alkvno39u109jgl1knfocyr9183ryo1hfo1c8n"
         export DATABASE_PASSWORD="mess"
        

    • Run python manage.py collectstatic
    • Test gunicorn by running gunicorn --bind 0.0.0.0:8000 mess.wsgi, and checking the website from browser.
      The website will not have any style, since gunicorn does not know about the CSS responsible for this
    • Create a gunicorn systemd service file and enable it
      • Create a new file by typing sudo nano /etc/systemd/system/gunicorn.service
      • This is a sample gunicorn.service file. You might have to make necessary modifications.

       [Unit]
       Description=gunicorn daemon
       After=network.target
      
       [Service]
       User=pi
       Group=www-data
       WorkingDirectory=/home/pi/mess
       EnvironmentFile=/home/pi/mess/django_environment_variables
       ExecStart=/usr/local/bin/gunicorn --access-logfile - --workers 1 --bind unix:/home/pi/mess/mess.sock mess.wsgi:application
      
       [Install]
       WantedBy=multi-user.target
      

      • Run sudo systemctl start gunicorn
      • Run sudo systemctl enable gunicorn
    • Setup Nginx
      • Run sudo nano /etc/nginx/sites-available/mess
      • This is a sample server block. You might have to make necessary modifications.

       server {
       	listen 80;
       	server_name <INSERT IP HERE>;
      
       	location = /favicon.ico { access_log off; log_not_found off; }
       	location /static/ {
       		root /home/pi/mess;
       	}
      
       	location / {
       		include proxy_params;
       		proxy_pass http://unix:/home/pi/mess/mess.sock;
       	}
       }
      

      • Run sudo ln -s /etc/nginx/sites-available/mess /etc/nginx/sites-enabled
      • Run sudo systemctl restart nginx
    • Open a browser and check the website. It should be up and running on port 80.
      If you are facing problems, please check the above link. The guide has some instructions about troubleshooting.

13. Set up RPi to run as a Kiosk

    • Im not writing specific instructions because the blog is very well written.
    • Notes
      • When I tried to use the while loop in .xsession, it didnt work.
      • For running sudo insserv /etc/init.d/aaa you might need to first install insserv by typing sudo apt-get install insserv
    • Request : For the splash image, use the IITG Logo