@omegajs/dht
Within this module lies the core engine driving Omega's Flock, an advanced implementation of the Distributed Hash Table (DHT) network structure.
Install Via L1FE's NPM
npm config set registry https://npm.l1fe.tech
npm install @omegajs/gateway
Install Via L1FE's Git Repository
git clone https://lab.l1fe.tech/omega/gateway.git
cd gateway
npm install
Built on top of dht-rpc.
The Omega DHT uses a series of holepunching techniques to make sure connectivity works on most networks,
and is mainly used to facilitate finding and connecting to peers using end to end encrypted Noise streams.
Usage
To try it out, first instantiate a DHT instance
import GATEWAY from '@omegajs/gateway'
const node = new GATEWAY()
Then on one computer listen for connections
const server = node.createServer()
server.on('connection', function (socket) {
console.log('Remote public key', socket.remotePublicKey)
process.stdin.pipe(socket).pipe(process.stdout)
})
const keyPair = GATEWAY.keyPair()
await server.listen(keyPair)
Then on another connect to the computer using the public key of the key-pair it is listening on
const socket = anotherGateway.connect(publicKey)
socket.on('open', function () {
})
process.stdin.pipe(socket).pipe(process.stdout)
API
const gateway = new GATEWAY([options])
Create a new Omega DHT gateway (node).
Options include:
{
bootstrap: ['host:port'],
keyPair
}
See dht-rpc for more options as OGateway inherits from that.
Note: The default bootstrap servers are publicly served on behalf of the commons. To run a fully isolated DHT, start one or more dht nodes with an empty bootstrap array (new GATEWAY({bootstrap:[]})
) and then use the addresses of those nodes as the bootstrap
option in all other dht nodes. You'll need at least one persistent DHT node for the network to be completely operational.
keyPair = DHT.keyPair([seed])
Use this method to generate the required keypair for DHT operations.
Returns an object with {publicKey, secretKey}
. publicKey
holds a public key buffer, secretKey
holds a private key buffer.
If you pass any options they are forwarded to dht-rpc.
await node.destroy([options])
Fully destroy this DHT node.
This will also unannounce any running servers.
If you want to force close the node without waiting for the servers to unannounce pass { force: true }
.
gateway = GATEWAY.bootstrapper(port, host, [options])
If you want to run your own Omega network use this method to easily create a bootstrap gateway node.
Creating P2P servers
const server = node.createServer([options], [onconnection])
Create a new server for accepting incoming encrypted P2P connections.
Options include:
{
firewall (remotePublicKey, remoteHandshakePayload) {
return true
}
}
You can run servers on normal home computers, as the DHT will UDP holepunch connections for you.
await server.listen(keyPair)
Make the server listen on a keyPair.
To connect to this server use keyPair.publicKey as the connect address.
server.refresh()
Refresh the server, causing it to reannounce its address. This is automatically called on network changes.
server.on('connection', socket)
Emitted when a new encrypted connection has passed the firewall check.
socket
is a NoiseSecretStream instance.
You can check who you are connected to using socket.remotePublicKey
and socket.handshakeHash
contains a unique hash representing this crypto session (same on both sides).
server.on('listening')
Emitted when the server is fully listening on a keyPair.
server.address()
Returns an object containing the address of the server:
{
host,
port,
publicKey
}
You can also get this info from node.remoteAddress()
minus the public key.
await server.close()
Stop listening.
server.on('close')
Emitted when the server is fully closed.
Connecting to P2P servers
const socket = node.connect(remotePublicKey, [options])
Connect to a remote server. Similar to createServer
this performs UDP holepunching for P2P connectivity.
Options include:
{
nodes: [...],
keyPair
}
socket.on('open')
Emitted when the encrypted connection has been fully established with the server.
socket.remotePublicKey
The public key of the remote peer.
socket.publicKey
The public key of the local socket.
Additional peer discovery
const stream = node.lookup(topic, [options])
Look for peers in the DHT on the given topic. Topic should be a 32 byte buffer (normally a hash of something).
The returned stream looks like this
{
from: { id, host, port },
to: { host, port },
peers: [ { publicKey, nodes: [{ host, port }, ...] } ]
}
To connect to the peers you should afterwards call connect
with those public keys.
If you pass any options they are forwarded to dht-rpc.
const stream = node.announce(topic, keyPair, [relayAddresses], [options])
Announce that you are listening on a key-pair to the DHT under a specific topic.
When announcing you'll send a signed proof to peers that you own the key-pair and wish to announce under the specific topic. Optionally you can provide up to 3 nodes, indicating which DHT nodes can relay messages to you - this speeds up connects later on for other users.
An announce does a parallel lookup so the stream returned looks like the lookup stream.
Creating a server using GATEWAY.createServer
automatically announces itself periodically on the key-pair it is listening on. When announcing the server under a specific topic, you can access the nodes it is close to using server.nodes
.
If you pass any options they are forwarded to dht-rpc.
await node.unannounce(topic, keyPair, [options])
Unannounce a key-pair.
If you pass any options they are forwarded to dht-rpc.
Mutable/immutable records
const { hash, closestNodes } = await node.immutablePut(value, [options])
Store an immutable value in the DHT. When successful, the hash of the value is returned.
If you pass any options they are forwarded to dht-rpc.
const { value, from } = await node.immutableGet(hash, [options])
Fetch an immutable value from the DHT. When successful, it returns the value corresponding to the hash.
If you pass any options they are forwarded to dht-rpc.
const { publicKey, closestNodes, seq, signature } = await node.mutablePut(keyPair, value, [options])
Store a mutable value in the DHT.
If you pass any options they are forwarded to dht-rpc.
const { value, from, seq, signature } = await node.mutableGet(publicKey, [options])
Fetch a mutable value from the DHT.
Options:
seq
- OPTIONAL, default 0
, a number which will only return values with corresponding seq
values that are greater than or equal to the supplied seq
option.latest
- OPTIONAL - default false
, a boolean indicating whether the query should try to find the highest seq before returning, or just the first verified value larger than options.seq
it sees.
Any additional options you pass are forwarded to dht-rpc.
Additional API
See dht-rpc for the additional APIs the DHT exposes.
CLI
You can start a DHT node in the command line:
npm install -g @omegajs/gateway
Run a DHT node:
ogateway
Or run multiple nodes:
ogateway --nodes 5
Note: by default it uses the mainnet bootstrap nodes.
Isolated DHT network
To create your own DHT network is as follows:
- Run your first bootstrap node:
ogateway --bootstrap --host (server-ip)
Important: it requires the port to be open.
Now your bootstrap node is ready to use at (server-ip):1776
, for example:
const dht = new DHT({ bootstrap: ['(server-ip):1776'] })
Note: You could configure some DNS for the bootstrap IP addresses.
For the network to be fully operational it needs at least one persistent node.
- Provide the first node by using your own bootstrap values:
ogateway --port 49738 --bootstrap (server-ip):1776
Important: it requires the port to be open too.
You need to wait ~30 mins for the node to become persistent.
Having persistent nodes in different places makes the network more decentralized and resilient!
For more information: examples/isolated-dht.mjs
License
MIT