[docs] add a docker method to generating VAPID keypair

README.md

@@ -48,7 +48,16 @@ When exposing your self-hosted Huly deployment to the internet, it's crucial to
 
 ## Generating Public and Private VAPID keys for front-end
 
-You'll need `Node.js` installed on your machine. Installing `npm` on Debian based distro:
+A VAPID key pair allows your self-hosted application server to deliver Web Push Notifications to your clients via push services.
+
+### Generate the VAPID keys
+
+A VAPID key pair can be generated by a plethora of methods, use whichever method is most convenient for you.\
+Some example methods are provided below.
+
+#### Using `Node.js` on your machine to generate VAPID keys:
+
+Install `npm` on Debian based distro:
 ```
 sudo apt-get install npm
 ```
@@ -72,6 +81,26 @@ asdfsadfasdfsfd
 
 =======================================
 ```
+
+#### Using `Node.js` in Docker to generate VAPID keys:
+Run this docker one-liner to generate a VAPID key pair:
+```
+docker run --rm node npm exec --package=web-push -- web-push generate-vapid-keys
+```
+It will generate both keys that looks like this:
+```
+=======================================
+
+Public Key:
+sdfgsdgsdfgsdfggsdf
+
+Private Key:
+asdfsadfasdfsfd
+
+=======================================
+```
+
+### Store your VAPID keys
 Keep these keys secure, as you will need them to set up your push notification service on the server.
 
 Add these keys into `compose.yaml` in section `services:front:environment`: