alertsquarer

An visual experience for rendering prometheus alerts

Prereqs

• 1 raspberry 3+
• nodejs
• 32x32 RGB-LED panels, one per team
• 5V 5A powersupply

Install and run

cd /opt
git clone https://github.com/dhtech/alertsquarer.git
cd alertsquarer
npm install

# to run via ts-node, start in sepatare terminal windows:
npm run devapi
npm run devmatrix

# to build ts to js and run
npm run build
# and in separate terminal windows:
npm run api
npm run matrix

Blacklist kernel module

The matrix driver doesn't work at all when the module snd_bcm2835 is loaded so it needs to be blacklisted.

echo "blacklist snd_bcm2835" > /etc/modprobe.d/no_rpi_sound.conf

systemctl

Autostart the services

Start the API

echo <<EOF >/etc/systemd/system/alertsquarer-api.service
[Unit]
Description=alertsquarer-api
After=network.target

[Service]
ExecStart=/usr/bin/npm run api
Restart=always
User=root
Group=root
Environment=PATH=/usr/bin:/usr/local/bin
Environment=NODE_ENV=production
WorkingDirectory=/opt/alertsquarer

[Install]
WantedBy=multi-user.target
EOF
systemctl daemon-reload
systemctl enable alertsquarer-api.service
systemctl start alertsquarer-api.service

Start the Matrix controller

echo <<EOF >/etc/systemd/system/alertsquarer-matrix.service
[Unit]
Description=alertsquarer-matrix
After=network.target

[Service]
ExecStart=/usr/bin/npm run matrix
Restart=always
User=root
Group=root
Environment=PATH=/usr/bin:/usr/local/bin
Environment=NODE_ENV=production
WorkingDirectory=/opt/alertsquarer

[Install]
WantedBy=multi-user.target
EOF
systemctl daemon-reload
systemctl enable alertsquarer-matrix.service
systemctl start alertsquarer-matrix.service

Troubleshooting

If the matrix-controller complains about bad JSON

Then there is multiple lines in the FIFO, we should fix that.

• stop both services
• remove the FIFO
• start the matrix controller first!
• start the api server.

If the matrix-controller just restarts too fast

You might have forgotten to disable snd_bcm2835, see above.

If both servers are running but no updates on the matrix

If the FIFO was recreated between that the API-server was started and the matrix controller started they might be trying to communicate on different inodes. Follow the steps for bad JSON above.

More information

The LED-library: https://github.com/hzeller/rpi-rgb-led-matrix/tree/master Has a lot of debug information

The Node binding: https://github.com/alexeden/rpi-led-matrix