gY0J4JnK

1const Mam = require('@iota/mam')
2const { asciiToTrytes, trytesToAscii } = require('@iota/converter')
3
4const mode = 'restricted'
5const secretKey = 'PASSWORDYEHIAAAAAAA'
6const provider = 'https://nodes.devnet.iota.org'
7
8const mamExplorerLink = `https://mam-explorer.firebaseapp.com/?provider=${encodeURIComponent(provider)}&mode=${mode}&key=${secretKey.padEnd(81, '9')}&root=`
9
10// Initialise MAM State
11let mamState = Mam.init(provider)
12
13// Set channel mode
14mamState = Mam.changeMode(mamState, mode, secretKey)
15
16// Publish to tangle
17const publish = async packet => {
18    // Create MAM Payload - STRING OF TRYTES
19    const trytes = asciiToTrytes(JSON.stringify(packet))
20    const message = Mam.create(mamState, trytes)
21
22    // Save new mamState
23    mamState = message.state
24
25    // Attach the payload
26    await Mam.attach(message.payload, message.address, 3, 9)
27
28    console.log('Published', packet, '\n');
29    return message.root
30}
31
32const publishAll = async () => {
33  const root = await publish({
34    message: 'Message from Alice',
35    timestamp: (new Date()).toLocaleString()
36  })
37
38  await publish({
39    message: 'Message from Bob',
40    timestamp: (new Date()).toLocaleString()
41  })
42
43  await publish({
44    message: 'Message from Charlie',
45    timestamp: (new Date()).toLocaleString()
46  })
47
48  return root
49}
50
51// Callback used to pass data out of the fetch
52const logData = data => console.log('Fetched and parsed', JSON.parse(trytesToAscii(data)), '\n')
53
54publishAll()
55  .then(async () => {
56
57    // Output asyncronously using "logData" callback function
58    const root = Mam.getRoot(mamState)
59    console.log("the root is",root)
60    await Mam.fetch(root, mode, secretKey, logData)
61    // Output syncronously once fetch is completed
62    const result = await Mam.fetch(root, mode, secretKey)
63    result.messages.forEach(message => console.log('Fetched and parsed', JSON.parse(trytesToAscii(message)), '\n'))
64
65    console.log(`Verify with MAM Explorer:\n${mamExplorerLink}${root}\n`);
66  })