Query Output Details

If you know an output Id, you can query the details of using the Node API through the iota.js library.

Connect to a Node

The first thing you will need to do is to connect to a node by instantiating a client using the SingleNodeClient() class.

const API_ENDPOINT = 'https://api.testnet.shimmer.network';
const client = new SingleNodeClient(API_ENDPOINT, {
  powProvider: new NeonPowProvider(),
});
const protocolInfo = await client.protocolInfo();

console.log(protocolInfo);

The code above uses the NeonPowProvider to calculate the PoW when submitting blocks. The NeonPowProvider executes native code and calculates the PoW faster.

The code above uses the the client.protocolInfo() function to retrieve metadata about the network, including the HRP for the BECH32 addresses, as mentioned when you generated the public address:

{
  "networkName": "testnet-1",
  "networkId": "1856588631910923207",
  "bech32Hrp": "rms",
  "minPowScore": 1500
}

Through the interface exposed by the iota.js SingleNodeClient, you can get the details of your output, for example:

const outputID =
  '0xcba9a6616df8e8e323d8203ea5d1a42e2e7c64dc9ead6b59f5d26bdc301efa540000';
const outputDetails = await client.output(outputID);
console.log(outputDetails);

{
  "metadata": {
    "blockId": "0x2b6a3301572f19e3596c2832e55c913ef9d3acc1ba345600ad76a8e4068b9f47",
    "transactionId": "0xcba9a6616df8e8e323d8203ea5d1a42e2e7c64dc9ead6b59f5d26bdc301efa54",
    "outputIndex": 0,
    "isSpent": false,
    "milestoneIndexBooked": 1692812,
    "milestoneTimestampBooked": 1666599405,
    "ledgerIndex": 1693193
  },
  "output": {
    "type": 3,
    "amount": "1000000000",
    "unlockConditions": [
      {
        "type": 0,
        "address": {
          "type": 0,
          "pubKeyHash": "0x696cc8b1e0d2c1e29fbf3a4f491c0c9dc730c6e4c4e0d0ab6011e9f1209af013"
        }
      }
    ]
  }
}

The output details contain two different groups of information:

• metadata that conveys the status of the output on the Ledger.

• The output details include the type of output (3 for value, i.e., basic outputs), the amount (in Glows), and the unlock conditions. You can observe that the unlock conditions contain the Ed22519 public key hash of your initial address. That means that only the one who controls the private key corresponding to that public key hash can unlock this output and use the corresponding funds. The protocol defines other possible unlock conditions that will be when you prepare the transaction.

Putting It All Together

By this point in the tutorial, your send-value-transactions.tsfile should look something like this:

import { Bip32Path, Bip39 } from '@iota/crypto.js';
import {
  Bech32Helper,
  ED25519_ADDRESS_TYPE,
  Ed25519Address,
  Ed25519Seed,
  generateBip44Address,
  IKeyPair,
  SingleNodeClient,
} from '@iota/iota.js';
import { Converter } from '@iota/util.js';
import { NeonPowProvider } from '@iota/pow-neon.js';

const API_ENDPOINT = 'https://api.testnet.shimmer.network';
const client = new SingleNodeClient(API_ENDPOINT, {
  powProvider: new NeonPowProvider(),
});
const protocolInfo = await client.protocolInfo();

console.log(protocolInfo);

const outputID =
  '0xcba9a6616df8e8e323d8203ea5d1a42e2e7c64dc9ead6b59f5d26bdc301efa540000';
const outputDetails = await client.output(outputID);
console.log(outputDetails);