JavaScript: fetch token price, consume custom_json data on Hive

Image generated with @karina.gpt in @cryptoshots.nft Discord server

I am in contact with the DappRadar team to fix how they track stuff  for Crypto Shots.

I ended up sending them some code snippets and decided to post them here too, in case I want to find them easily in the future.

---

1. Calculate the $ worth of a token transfer

HIVE:

var getHiveEngineTokenPrice = async ({ tokenName }) => {
  const tokenInfoUrl = `https://api.hive-engine.com/rpc/contracts`;
  const tokenInfoBody = {
    "jsonrpc":"2.0",
    "method":"find",
    "params": {
        "contract":"market",
        "table":"metrics",
        "query":{ "symbol": tokenName },
        "limit": 1,
        "offset": 0,
        "indexes":[]
    },
    "id":1
  };
  const tokenInfoResponse = await fetch(tokenInfoUrl, {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify(tokenInfoBody),
  });
  const tokenInfoData = await tokenInfoResponse.json();
  const lastPrice = tokenInfoData.result[0].lastPrice;
  console.log(`$${tokenName} current price on Hive-Engine: ${lastPrice} HIVE`);
  const hivePriceUrl = `https://api.coingecko.com/api/v3/simple/price?ids=hive&vs_currencies=usd`;
  fetch(hivePriceUrl)
    .then(response => response.json())
    .then(data => {
      const priceUSD = data.hive.usd;
      console.log(`HIVE current price is $${priceUSD}`);
      const tokenPriceUSD = lastPrice * priceUSD;
      console.log(`The current price of $${tokenName} in USD is $${tokenPriceUSD.toFixed(4)}.`);
    });
};

var tokenName = 'DOOM';
getHiveEngineTokenPrice({ tokenName });

 
WAX:

var getFungibleTokenPrice = async ({ tokenPair }) => {
const { tokenName, cryptoName, marketNumber } = tokenPair;
const cryptoNameLc = cryptoName.toLowerCase();
  const data = await fetch(`https://wax.alcor.exchange/api/markets/${marketNumber}/deals`).then(res => res.json());
  const lastTransactionPrice = data[0].unit_price;
  console.log(`$${tokenName} current price on the open market: ${lastTransactionPrice} ${cryptoName}`);
  fetch(`https://api.coingecko.com/api/v3/simple/price?ids=${cryptoNameLc}&vs_currencies=usd`)
    .then(response => response.json())
    .then(data => {
    const priceUSD = data[cryptoNameLc].usd;
    console.log(`$${cryptoName} current price is $ ${priceUSD}`);
    const tokenPriceUSD = lastTransactionPrice * priceUSD;
    console.log(`The current price of $${tokenName} is $ ${tokenPriceUSD.toFixed(4)}.`);
  });
};

var tokenPair = {
  tokenName: 'BOOM',
  contract: 'csboomcsboom',
  cryptoName: 'WAX',
  marketNumber: 368,
};
getFungibleTokenPrice({ tokenPair });

---

2. How to consume custom_json  operations

...broadcasted on the Hive chain (eg. from a game/Dapp).

This is what such operations look like:

block_num   82670298
expiration  2024-02-09T23:53:30
extensions  []
operations  [["custom_json", {"id": "ssc-mainnet-hive", "json": "{\"contractName\":\"tokens\",\"contractAction\":\"stake\",\"contractPayload\":{\"symbol\":\"DOOM\",\"to\":\"athunderstruck\",\"quantity\":\"6.6700\",\"memo\":\"Crypto Shots PVP Alpha reward. GG!\"}}", "required_auths": ["cryptoshots.tips"], "required_posting_auths": [] }]]
ref_block_num   29401
ref_block_prefix    2126063433
signatures  [ "1f5054e3996f04805b4a7b070c78d94cd50ee8097094f832335b7119199ca421470e6a5a6c6e63c6dc272eb6ca549761b4c176f209eb3de0a049ccbbc9e3472057" ]
transaction_id  9ee3b9672bf71e0e5d853cb44dfb275ed2fd46a8
transaction_num 80

_{Example: https://hiveblockexplorer.com/tx/9ee3b9672bf71e0e5d853cb44dfb275ed2fd46a8}

 
Example of how to stream blocks of the Hive blockchain and parse custom_json 
operations found in blocks:

const fetch = require('node-fetch');
const { Client, Blockchain } = require('@hiveio/dhive');

const fetchHealthyHiveNode = () => fetch(
  'https://beacon.peakd.com/api/nodes',
  {
    credentials: 'omit',
    headers: { Accept: 'application/json' },
    method: 'GET',
  },
)
  .then((res) => res.json())
  .then((allNodes) => {
    const healthyNodes = allNodes.filter(({ score } = {}) => score === 100);
    return ({ hiveNode: healthyNodes[0].endpoint });
  })
  .catch((fetchErr) => ({ err: `Url fetch failed: ${fetchErr}` }));

const streamBlocks = async () => {
  const { err, hiveNode } = await fetchHealthyHiveNode();
  if (err) return;
  const client = new Client(hiveNode);
  const blockchain = new Blockchain(client);
  console.log('Streaming blocks from', hiveNode);
  blockchain.getBlockStream()
    .on('data', (block) => {
      console.log(`Received block #${block.block_id} containing ${block.transactions.length} transactions`);
      block.transactions.forEach(
        tx => tx.operations.forEach(
          op => op[0] === 'custom_json' && console.log(op[1]),
        )
      );
    })
    .on('error', console.error);
};
streamBlocks();

---

That's all folks!

 
 
 
If you spare a vote, please vote for these witnesses! 😎
 

• @keys-defender:
  https://vote.hive.uno/@keys-defender
   
• @crypto-shots:
  https://vote.hive.uno/@crypto-shots