Get PagerDuty notifications to flash your bedside lamp

This article explains how I used AWS SES, AWS SNS, ngrok, nginx, Home Assistant and a TP-Link Kasa Smart TP-Link (KP400) to flash a beside lamp when I get paged on PagerDuty, before it falls back to a sound notification on my phone.

Note: there are probably simpler methods. I didn’t have access to the PagerDuty API and had to rely on emails for notifications.

Overview

Here’s the high-level configuration:

• Configure Home Assistant to flash a lamp when it receives a webhook (for example on: /api/webhook/something).
• Add an nginx container alongside Home Assistant to only expose this webhook endpoint. I didn’t want to expose my entire Home Assistant setup on the Internet.
• Use ngrok to expose the nginx container’s port publicly on the Internet. You could very well forward a port from your home router/NAT device and rely on your current public IP instead.
• Configure AWS SES to receive email (for example on: x@y.xyz) and forward them to an SNS topic.
• Add a webhook subscriber https://$HOSTNAME/api/webhook/something to the SNS topic.
• Configure PagerDuty to send email notifications to that email address (for example: x@y.xyz).

Prerequisites

The instructions below assume that:

• You already have Home Assistant setup on a host
• You’ve paired a smart plug device with it
• You own a domain name
• You have basic knowledge of Docker, nginx, AWS SES, AWS SNS and PagerDuty configuration

Home Assistant Configuration

1. Configuration > Automations > Add Automation > Start with an empty automation

2. Click on the top right three dots and press “Edit as YAML”.

3. You can use this sample configuration. It might be suboptimal (didn’t get to loops), it’s the first one I create. Replace something by your webhook path. This should be enough to expose a webhook that will trigger a lamp to flash with 1 second delay between turn on and turn off.

   1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28

   alias: PagerDuty Notification description: '' trigger: - platform: webhook webhook_id: something condition: [] action: - type: turn_on device_id: 1234 entity_id: switch.kasa_smart_plug_4d21_0 domain: switch - delay: 1 - type: turn_off device_id: 1234 entity_id: switch.kasa_smart_plug_4d21_0 domain: switch - delay: 1 - type: turn_on device_id: 1234 entity_id: switch.kasa_smart_plug_4d21_0 domain: switch - delay: 1 - type: turn_off device_id: 1234 entity_id: switch.kasa_smart_plug_4d21_0 domain: switch - delay: 1 mode: single

At this point, you should be able to send a request to http://homeassistant:8123/api/webhook/something to trigger the lamp to flash.

Nginx container on the Home Assistant Raspberry Pi

I wrote this configuration file to /mnt/data/docker/nginx/nginx.conf:

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26

user  nginx;
worker_processes  1;

error_log  /var/log/nginx/error.log warn;
pid        /var/run/nginx.pid;

events {
    worker_connections  1024;
}

http {
    include       /etc/nginx/mime.types;
    default_type  application/octet-stream;
    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';
    access_log  /var/log/nginx/access.log  main;
    sendfile        on;
    keepalive_timeout  65;
    server {
        server_name _;
        location /api/webhook {
            proxy_pass http://127.0.0.1:8123/api/webhook;
        }
    }
}

And then started a container with:

• image nginx:latest
• configuration mounted on /mnt/data/docker/nginx/nginx.conf:/etc/nginx/nginx.conf:ro
• expose port 80

At this point, you should be able to send a request to http://homeassistant:80/api/webhook/something to trigger the lamp to flash.

ngrok

I downloaded ngrok on /mnt/data, prepared a sample configuration, and started it:

1
2
3
4
5
6

authtoken: ABCD1234
tunnels:
  hass:
    proto: http
    addr: 80
    subdomain: YOUR_SUBDOMAIN

At this point, you should be able to send a request to https://YOUR_SUBDOMAIN.ngrok.io/api/webhook/something to trigger the lamp to flash.

AWS SES and SNS configuration

1. Create a new SNS topic.
2. Follow this documentation to setup SES to receive emails. At step 3, configure the action to publish to your SNS topic instead of S3.
3. Subscribe your webhook URL https://YOUR_SUBDOMAIN.ngrok.io/api/webhook/something to the SNS topic.

At this point, you should be able to send an email to x@y.xyz to trigger the lamp to flash.

PagerDuty

Add the extra email address (example taken from above: x@y.xyz) in your PagerDuty user profile. Configure notifications to trigger on this email address first if you want the lamp to flash before anything else like I did.