DISCLAIMER: WORK IN PROGRESS/NOT PRODUCTION-READY
gun
runs a GUN server from your command line
GUN is a distributed, offline-first, realtime graph database engine with built-in encryption. It's a small, easy, and fast data sync and storage system that runs everywhere JavaScript does.
yarn global add gun-cli OR npm install -g gun-cli
start a local gun peer
gun --host 127.0.0.1 --watch foo.bar
access it from your browser
<html>
<script src="https://cdn.jsdelivr.net/npm/gun/gun.js"></script>
<script>
const gun = Gun('http://127.0.0.1:8765/gun')
gun.get('foo').get('bar').put('baz ' Date.now())
</script>
</html>
see foo.bar
update in your command line
22:41:50 foo.bar => "baz 1570135310381"
gun print flux.bar --file false --peers 127.0.0.1 --debounce 200 --timeout 2000
This will try to load flux.bar
from http://127.0.0.1:8765/gun
(extending the provided
IP to a full gun URL with the default port 8765
). If the query does not resolve within
two seconds, the attempt will timeout. However, if the peer can resolve our query, the
answers that do come streaming in are debounced with a 200 ms interval, i.e. we try to
wait for a full .load()
of the data we're interested in.
ls ./mydomain-certs
> ca.pem cert.pem key.pem
gun --port 443 --certs ./mydomain-certs
Under the hood, this just uses require('https').createServer()
with the respective
params ca
, cert
, and key
.
start a small mesh network of gun servers, each listening on a different IP and saving data in a different folder.
gun --host 127.0.0.1 --peers 127.0.0.3,127.0.0.4 --file ./data1 # 1
gun --host 127.0.0.2 --peers 127.0.0.3,127.0.0.4 --file ./data2 # 2
gun --host 127.0.0.3 --peers 127.0.0.1,127.0.0.2 --file ./data3 # 3
gun --host 127.0.0.4 --peers 127.0.0.1,127.0.0.2 --file ./data4 # 4
connect two browsers, A and B, over this network
Browser A
<html>
<script src="https://cdn.jsdelivr.net/npm/gun/gun.js"></script>
<script>
const peers = [
'http://127.0.0.1:8765/gun',
'http://127.0.0.2:8765/gun'
]
const gun = Gun({peers})
gun.get('foo').get('heartbeat').on(heartbeat => {
const time = new Date(heartbeat).toLocaleTimeString()
console.log(`last heartbeat was at ${time}`)
})
</script>
</html>
Browser B
<html>
<script src="https://cdn.jsdelivr.net/npm/gun/gun.js"></script>
<script>
const peers = [
'http://127.0.0.3:8765/gun',
'http://127.0.0.4:8765/gun'
]
const gun = Gun({peers})
setInterval(() => {
gun.get('foo').get('heartbeat').put(Date.now())
}, 1000)
</script>
</html>
now play around with shutting down individual peers and bringing them back online
As long as there is a path through the mesh network, the heartbeats will propagate from B to A.
But if peers 1 and 2 (or peers 3 and 4) simultainiously go down, A and B are seperated and updates won't go through. However, GUN peers will try to reestablish the connection to a lost peer, so as soon as you bring one of the peers back online, they will reconnect and updates will go through again.
gun [command] [options]
COMMANDS
serve [default] start a gun server on http
print NODEPATH load NODEPATH and print as JSON
version print version numbers and exit
GENERAL OPTIONS
--file PATH ./gundata/ set file parameter of Gun()
--peers STRING comma-seperated list of URLs and IPs
(IPs are expanded to http://IP:8765/gun)
--no-color do not use any colors in output
--debug print GUN debug info
--silent reduce command line output
--repl go into a repl (with gun instace)
[serve] OPTIONS
--host STRING 0.0.0.0 set the ip to listen on
--port NUMBER 8765 set the port to listen on
--watch PATH log changes with gun.path(PATH).on()
--certs PATH ./certs use https with cert files from PATH
(key.pem, cert.pem, ca.pem)
--nocerts disable auto-discovery of ./certs
--webrtc false load lib/webrtc
[print] OPTIONS
--out FILENAME write to FILENAME instead of stdout
--indent STRING indent characters for JSON output
--debounce NUMBER 50 debounce .load() to resolve nested data
set to 0 to disable debouncing
--timeout NUMBER 1000 wait this much for answers to your request