├── .gitignore
├── client.js
├── connection.js
├── package.json
└── server.js


/.gitignore:
--------------------------------------------------------------------------------
1 | /node_modules/
2 | 


--------------------------------------------------------------------------------
/client.js:
--------------------------------------------------------------------------------
 1 | const Automerge = require('automerge')
 2 | const Connection = require('./connection')
 3 | const net = require('net')
 4 | const HOST = '127.0.0.1'
 5 | const PORT = 9876
 6 | const docSet = new Automerge.DocSet()
 7 | 
 8 | // Print out the document whenever it changes
 9 | docSet.registerHandler((docId, doc) => {
10 |   console.log(`[${docId}] ${JSON.stringify(doc)}`)
11 | })
12 | 
13 | // Make a change to the document every 3 seconds
14 | setInterval(() => {
15 |   let doc = docSet.getDoc('example')
16 |   if (doc) {
17 |     doc = Automerge.change(doc, doc => {
18 |       doc.clientNum = (doc.clientNum || 0) + 1
19 |     })
20 |     docSet.setDoc('example', doc)
21 |   }
22 | }, 3000)
23 | 
24 | const socket = new net.Socket()
25 | let connection
26 | 
27 | // Connecting to a TCP port
28 | socket.connect(PORT, HOST, () => {
29 |   console.log(`[${HOST}:${PORT}] connected`)
30 |   connection = new Connection(docSet, socket)
31 | })
32 | 
33 | // Receiving data from the server
34 | socket.on('data', (data) => {
35 |   if (!(data instanceof Buffer)) {
36 |     data = Buffer.from(data, 'utf8')
37 |   }
38 |   connection.receiveData(data)
39 | })
40 | 
41 | socket.on('close', () => {
42 |   console.log(`[${HOST}:${PORT}] connection closed`)
43 | })
44 | 
45 | socket.on('error', (err) => {
46 |   console.log(`[${socket.remoteAddress}:${socket.remotePort}] error: ${err}`)
47 | })
48 | 


--------------------------------------------------------------------------------
/connection.js:
--------------------------------------------------------------------------------
 1 | const Automerge = require('automerge')
 2 | 
 3 | class Connection {
 4 |   constructor (docSet, socket) {
 5 |     this.automerge = new Automerge.Connection(docSet, msg => this.sendMsg(msg))
 6 |     this.socket = socket
 7 |     this.buffer = Buffer.alloc(0)
 8 |     this.automerge.open()
 9 |   }
10 | 
11 |   receiveData (data) {
12 |     this.buffer = Buffer.concat([this.buffer, data])
13 | 
14 |     // If there is enough data in the buffer, decode it into messages
15 |     while (true) {
16 |       if (this.buffer.length < 4) break
17 | 
18 |       const msglen = this.buffer.readInt32BE(0)
19 |       if (this.buffer.length < msglen + 4) break
20 | 
21 |       const msg = JSON.parse(this.buffer.toString('utf8', 4, msglen + 4))
22 |       this.buffer = this.buffer.slice(msglen + 4)
23 |       //console.log('Received:', msg)
24 |       this.automerge.receiveMsg(msg)
25 |     }
26 |   }
27 | 
28 |   sendMsg (msg) {
29 |     if (!this.socket) return
30 |     //console.log('Sending:', msg)
31 |     const data = Buffer.from(JSON.stringify(msg), 'utf8')
32 |     const header = Buffer.alloc(4)
33 |     header.writeInt32BE(data.length, 0)
34 |     this.socket.write(header)
35 |     this.socket.write(data)
36 |   }
37 | 
38 |   close () {
39 |     if (!this.socket) return
40 |     this.socket.end()
41 |     this.socket = null
42 |   }
43 | }
44 | 
45 | module.exports = Connection
46 | 


--------------------------------------------------------------------------------
/package.json:
--------------------------------------------------------------------------------
1 | {
2 |   "dependencies": {
3 |     "automerge": "0.9.1"
4 |   },
5 |   "devDependencies": {
6 |   }
7 | }
8 | 


--------------------------------------------------------------------------------
/server.js:
--------------------------------------------------------------------------------
 1 | const Automerge = require('automerge')
 2 | const Connection = require('./connection')
 3 | const net = require('net')
 4 | const HOST = '0.0.0.0'
 5 | const PORT = 9876
 6 | 
 7 | // Initialise an example document
 8 | const docSet = new Automerge.DocSet()
 9 | const initDoc = Automerge.change(Automerge.init(), doc => doc.hello = 'Hi!')
10 | docSet.setDoc('example', initDoc)
11 | 
12 | // Print out the document whenever it changes
13 | docSet.registerHandler((docId, doc) => {
14 |   console.log(`[${docId}] ${JSON.stringify(doc)}`)
15 | })
16 | 
17 | // Make a change to the document every 3 seconds
18 | setInterval(() => {
19 |   let doc = docSet.getDoc('example')
20 |   doc = Automerge.change(doc, doc => {
21 |     doc.serverNum = (doc.serverNum || 0) + 1
22 |   })
23 |   docSet.setDoc('example', doc)
24 | }, 3000)
25 | 
26 | // This function is called every time a client connects to the server socket
27 | function handler(socket) {
28 |   console.log(`[${socket.remoteAddress}:${socket.remotePort}] connected`)
29 |   const connection = new Connection(docSet, socket)
30 | 
31 |   // Receiving data from the client
32 |   socket.on('data', (data) => {
33 |     if (!(data instanceof Buffer)) {
34 |       data = Buffer.from(data, 'utf8')
35 |     }
36 |     connection.receiveData(data)
37 |   })
38 | 
39 |   socket.on('close', (data) => {
40 |     console.log(`[${socket.remoteAddress}:${socket.remotePort}] connection closed`)
41 |     connection.close()
42 |   })
43 | 
44 |   socket.on('error', (err) => {
45 |     console.log(`[${socket.remoteAddress}:${socket.remotePort}] error: ${err}`)
46 |   })
47 | }
48 | 
49 | // Listen on a TCP port
50 | net.createServer(handler).listen(PORT, HOST)
51 | console.log(`Listening on ${HOST}:${PORT}`)
52 | 


--------------------------------------------------------------------------------