Compile geth from https://github.com/bas-vk/go-ethereum/tree/whisper-api
Setup private network: genesis file: https://gist.github.com/bas-vk/bbd75fcbcdd73b64cbb864f78fe49988
geth --datadir /tmp/whisper init
Get chat.js
from https://gist.github.com/bas-vk/0961a9c945b3761eee7bfc4f70db75a9
Start node:
geth --datadir /tmp/whisper --shh --preload </path/to/downloaded/chat.js> console 2>/dev/null
Add peer: admin.addPeer("enode://3b48b9200bd964fee986358edf721de0c322339b36a73016e9af4de9e3b5d6da090807596b9dfb52ee35056005211c51f3744d728edf06c4c6567a309d29c967@[85.146.5.133]:30303")
Set username (optional):
chat.setUsername("abcd")
Join chat box:
chat.join("geth")
Say something:
chat.say("my message")