Minimal kiosk

Possible improvements :

• in "today" case : show wind data if rain data < 5mm (light rain)
• add "this afternoon" when datetime < 12:00 and show "tomorrow" when datetime >= 12:00
• simplify configuration

1. Prerequisites

• Download Raspbian Lite in its latest version (in 2018 : Stretch). https://www.raspberrypi.org/downloads/raspbian/

• Download Etcher. https://etcher.io/

2. Setup SD Card

Burn Raspbian Lite .iso with Etcher on your SD Card. Insert the SD Card in your Raspberry Pi. Boot.

3. Configure Raspbian Lite

Verify Internet connection

Verify that the internet connection is OK.

Initialization

Type sudo raspi-config.

Change keyboard layout

It will be easier to type the commands.

Choose Localisation Options.

Choose Keyboard Layout.

Continue the setup process while selecting your desired keyboard layout.

In my case : Azerty layout with French keyboard.

Change timezone

It will be necessary to have a reliable date/time on your screen.

Choose Localisation Options.

Choose Timezone.

Select your Country/City.

In my case : Europe/Paris.

(Optional) Configure Proxy

Type sudo nano /etc/environment.

Fille the document with :

export http_proxy="http://proxyaddress:port/"
export https_proxy="http://proxyaddress:port/"

Update the Pi

Type sudo apt-get update && sudo apt-get upgrade -y.

Create a new user

For security reason we will create a new user and delete piuser.

Create new user

We will choose as username : mounier.

Add new user

Type sudo adduser mounier.

Type a strong password for this user.

Give user privileges

Type sudo adduser mounier sudo.

Type sudo usermod -a -G video mounier.

Delete pi user

Type exit to logout pi user.

Type the credentials for your new user, mounier in this example.

Then, type sudo deluser --remove-home pi.

Extra security

As another security, be sure each time sudo is used a password is prompted.

Type sudo nano /etc/sudoers.d/010_pi-nopasswd.

Edit the document to the following :

mounier ALL=(ALL) PASSWD: ALL

Auto login our new user

Type sudo raspi-config.

Select Boot options then Console/Autologin (second choice).

Reboot typing reboot.

mounier user will be auto-logged. Each time sudo command is used, a password will be prompted.

4. Configure Kiosk functionnality

Install & configure Kiosk utilites

Import the web page

Minimal kiosk comes with a .html page all written in HTML/CSS/JavaScript. It shows :

• Date & time
• Weather (thanks to the Meteorologisk Institutt of Norway https://api.met.no/)
• a Google Slide

You can edit the JavaScript constants in js/config.js. Don't forget to copy config.sample.js to config.js with your own configuration.

The document is not exempt of bugs and is badly internationalized. Please, open issues to propose me solutions.

---

You have two methods :

Static

Mount your SD Card on your computer. Be sure that you can see ext4 format drive.

In the folder home/mounier/ create a folder named minimal_kiosk and copy/paste the page and its dependances.

Dynamic (preference)

Install git. Type sudo apt-get install git.

Type cd /home/mounier.

Type git clone https://github.com/valsou/minimal_kiosk.

Type : cd minimal_kiosk.

Let's create a .gitignore to ignore our configuration file.

cp js/config.sample.js js/config.js
nano .gitignore

Insert js/config.js and save the file.

Now you can edit your own configuration file. Each update, the config.sample.js file may be updated, but not yours.

Minimal environment

Type sudo apt-get install --no-install-recommends xserver-xorg x11-xserver-utils xinit openbox.

Browser (Chromium)

Type sudo apt-get install --no-install-recommends chromium-browser.

Configure Openbox

Type sudo nano /etc/xdg/openbox/autostart and edit the document as following :

# Disable any form of screen saver / screen blanking / power management
xset s off
xset s noblank
xset -dpms

# Allow quitting the X server with CTRL-ATL-Backspace
setxkbmap -option terminate:ctrl_alt_bksp

# Start Chromium in kiosk mode
sed -i 's/"exited_cleanly":false/"exited_cleanly":true/' ~/.config/chromium/'Local State'
sed -i 's/"exited_cleanly":false/"exited_cleanly":true/; s/"exit_type":"[^"]\+"/"exit_type":"Normal"/' ~/.config/chromium/Default/Preferences
chromium-browser --disable-infobars --kiosk 'http://your-url-here'

In our case the URL will be : /home/mounier/minimal_kiosk/index.html.

Try it !

Try to launch the web page. Type startx -- -nocursor.

A GUI environment is launched and Chromium should open the web page.

To exit the Kiosk press on your keyboard CTRL+ALT+BACK SPACE.

If startx shows an error, try to delete .Xauthority file and reboot.

Type sudo rm -R /home/mounier/.Xauthority.

Type reboot.

Open Kiosk automatically on Boot

Type nano /home/mounier/.bash_profile and edit the document as following :

[[ -z $DISPLAY && $XDG_VTNR -eq 1 ]] && startx -- -nocursor

If you have chosen to import the kiosk page dynamically, edit the document as following :

[[ -z $DISPLAY && $XDG_VTNR -eq 1 ]] && cd /home/mounier/minimal_kiosk && git pull && startx -- -nocursor

This way, each time Kiosk is launched, the web page is updated.

Configure Display resolution (if needed)

In most cases the TV is 1080p (Full HD) compatible. So, we want a 1920x1080 (16/9) resolution.

Type sudo nano /boot/config.txt.

On the document, edit those lines as following :

disable_overscan=1
hdmi_drive=2
hdmi_group=1
hdmi_mode=16

Automation (cron)

We can automate :

• the screen extinction, to save energy.
• the browser/GUI environment extinction, to save bandwith
• updates of the web page from Github.com

We edit the cron file of our user. Type crontab -e.

Edit the document as following :

0 7 * * * vcgencmd display_power 1
0 19 * * * vcgencmd display_power 0
0 19 * * * killall xinit
50 6 * * * pkill -KILL -u mounier
0 0 * * * cd /home/mounier/minimal_kiosk && git pull

In the order :

• Every day at 07:00 AM -> power on the screen
• Every day at 07:00 PM -> power off the screen
• Every day at 07:00 PM -> shutdown GUI environment/chromium
• Every day at 6:50 AM -> open GUI environment/chromium
• Every day at midnight update git repo