계정 구독 및 업데이트

import { subscribe, CommitmentLevel, SubscribeUpdate, LaserstreamConfig } from 'helius-laserstream';
import bs58 from 'bs58';

// Utility function to recursively convert Buffer objects to base58 strings
function convertBuffersToBase58(obj: any): any {
  if (obj === null || obj === undefined) {
    return obj;
  }
  
  if (Buffer.isBuffer(obj)) {
    return bs58.encode(obj);
  }
  
  if (Array.isArray(obj)) {
    return obj.map(convertBuffersToBase58);
  }
  
  if (typeof obj === 'object') {
    const result: any = {};
    for (const key in obj) {
      if (obj.hasOwnProperty(key)) {
        result[key] = convertBuffersToBase58(obj[key]);
      }
    }
    return result;
  }
  
  return obj;
}

async function main() {
  console.log('🏦 Basic Account Subscription Example');

  const config: LaserstreamConfig = {
    apiKey: 'YOUR_API_KEY', // from https://dashboard.helius.dev/
    endpoint: 'https://laserstream-mainnet-ewr.helius-rpc.com', // pick the closest region
  };

  const request = {
    accounts: {
      "token-accounts": {
        account: [], // Specific account pubkeys (empty = all)
        owner: ["TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA"], // Token program
        filters: [
          {
            // Only token accounts (165 bytes)
            datasize: 165
          }
        ]
      }
    },
    commitment: CommitmentLevel.CONFIRMED,
    transactions: {}, slots: {}, transactionsStatus: {}, blocks: {}, blocksMeta: {}, entry: {}, accountsDataSlice: []
  };

  const stream = await subscribe(
    config,
    request,
    async (update: SubscribeUpdate) => {
      const readableUpdate = convertBuffersToBase58(update);
      console.log('🏦 Account Update:', JSON.stringify(readableUpdate, null, 2));
    },
    async (err) => console.error('❌ Stream error:', err)
  );

  console.log(`✅ Account subscription started (id: ${stream.id})`);

  process.on('SIGINT', () => {
    console.log('\n🛑 Cancelling stream...');
    stream.cancel();
    process.exit(0);
  });
}

main().catch(console.error);

🏦 Basic Account Subscription Example
✅ Account subscription started (id: xyz789)

🏦 Account Update: {
  "filters": ["token-accounts"],
  "account": {
    "account": {
      "pubkey": "BKMHWYLAX4un3HUbR7a3u9jPmzCiLNa4mSj1RiX11eWF",
      "lamports": "2039280",
      "owner": "TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA",
      "rentEpoch": "18446744073709551615",
      "data": "2NUx6Xw9QkmgJCyYUP3d8TPsjJhUpSM7hcy9Fi1juGc6g9DrpPFyGyvBZzu9qiAjFtyEDbNiLHYFJsq1dD5Wxr4LPcF9Dqs4AJa15L1N92pfinnoKVfCsVCcybhV1iwkCCTMeMyxTRA4tqJm6MrLwgKG3HmmwVdhsEuXjSsGJFXGzgfgPHucVzBEgAqcpH9JPpoaQyis2MFwRJLjenxzkE8xJzWHv1Zk2T",
      "writeVersion": "2697618495",
      "txnSignature": "5C9Hr5nG2j8eQz6inxPmfyjbYdmXddzUDyR1iQgEnjYQ3RNvuP4Zzc8t1enLNy7Rk8KNCtQPEQztENYWxkt9GaVD"
    },
    "slot": "352366983"
  },
  "createdAt": "2025-07-10T11:56:22.027Z"
}

accounts: {
  "all-token-program-accounts": {
    owner: ["TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA"] // ❌ Overwhelming!
  }
}

accounts: {
  "token-accounts-only": {
    owner: ["TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA"],
    filters: [{ datasize: 165 }] // ✅ Only standard token accounts
  }
}

pub struct Account {
    pub mint: Pubkey,                    // 32 bytes
    pub owner: Pubkey,                   // 32 bytes  
    pub amount: u64,                     // 8 bytes
    pub delegate: COption<Pubkey>,       // 4 + 32 bytes
    pub state: AccountState,             // 1 byte
    pub is_native: COption<u64>,         // 4 + 8 bytes
    pub delegated_amount: u64,           // 8 bytes
    pub close_authority: COption<Pubkey> // 4 + 32 bytes
}
// Total: 32+32+8+36+1+12+8+36 = 165 bytes

Base58 data: 2NUx6Xw9QkmgJCyYUP3d8TPsjJhUpSM7hcy9Fi1juGc6g9...

const USDC_MINT = "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v";

const request = {
  accounts: {
    "usdc-only": {
      owner: ["TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA"],
      filters: [
        { datasize: 165 },                    // Standard token accounts only
        { 
          memcmp: {
            offset: 0,                         // Mint address starts at byte 0
            base58: USDC_MINT                  // Match this specific mint
          }
        }
      ]
    }
  },
  // ... other config
};

import { subscribe, CommitmentLevel, SubscribeUpdate, LaserstreamConfig } from 'helius-laserstream';
import bs58 from 'bs58';

async function main() {
  console.log('USDC Account Monitor');

  const config: LaserstreamConfig = {
    apiKey: 'YOUR_API_KEY', // from https://dashboard.helius.dev/
    endpoint: 'https://laserstream-mainnet-ewr.helius-rpc.com', // pick the closest region
  };

  const USDC_MINT = "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v";

  const request = {
    accounts: {
      "usdc-accounts": {
        account: [],
        owner: ["TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA"],
        filters: [
          { datasize: 165 },                           // Standard token accounts
          { memcmp: { offset: 0, base58: USDC_MINT } } // Only USDC
        ]
      }
    },
    commitment: CommitmentLevel.CONFIRMED,
    transactions: {}, slots: {}, transactionsStatus: {}, blocks: {}, blocksMeta: {}, entry: {}, accountsDataSlice: []
  };

  const stream = await subscribe(
    config,
    request,
    async (update: SubscribeUpdate) => {
      explainAccountUpdate(update);
    },
    async (err) => console.error('Stream error:', err)
  );

  console.log(`Account monitor started (id: ${stream.id})`);

  process.on('SIGINT', () => {
    console.log('\nCancelling stream...');
    stream.cancel();
    process.exit(0);
  });
}

function explainAccountUpdate(update: SubscribeUpdate) {
  if (!update.account) return;
  
  const account = update.account.account;
  
  // Decode the key addresses
  const tokenAccountAddress = bs58.encode(account.pubkey);
  const transactionSignature = account.txnSignature ? bs58.encode(account.txnSignature) : 'Unknown';
  
  // Extract and decode the token account data (165 bytes)
  const walletOwner = bs58.encode(account.data.slice(32, 64));       // Bytes 32-63: Owner
  const tokenAmount = account.data.readBigUInt64LE(64);              // Bytes 64-71: Amount
  const usdcAmount = Number(tokenAmount) / 1_000_000;                // Convert to USDC (6 decimals)
  
  console.log(`Account: ${tokenAccountAddress}`);
  console.log(`Owner: ${walletOwner}`);
  console.log(`Balance: ${usdcAmount.toLocaleString()} USDC`);
  console.log(`Slot: ${update.account.slot}`);
  console.log(`Transaction: ${transactionSignature.slice(0, 8)}...`);
  console.log('---');
}

main().catch(console.error);

USDC Account Monitor
Account monitor started (id: abc123)

Account: 7xKXtg2CW87d97TXJSDpbD5jBkheTqA83TZRuJosgAsU
Owner: 9WzDXwBbmkg8ZTbNMqUxvQRAyrZzDsGYdLVL9zYtAWWM
Balance: 1,500 USDC
Slot: 352154103
Transaction: 5v8fy0eJ...
---
Account: BQy5rNRxLfcaK6554PMzsg4VJsFXzwGnAnayb8TZKgZX
Owner: HN7cABqLq46Es1jh92dQQisAq662SmxELLLsHHe4YWrH
Balance: 0 USDC
Slot: 352154103
Transaction: 5v8fy0eJ...
---

accounts: {
  "specific-accounts": {
    account: [
      "7xKXtg2CW87d97TXJSDpbD5jBkheTqA83TZRuJosgAsU",
      "BQy5rNRxLfcaK6554PMzsg4VJsFXzwGnAnayb8TZKgZX"
    ]
  }
}

accounts: {
  "high-value-usdc": {
    owner: ["TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA"],
    filters: [
      { datasize: 165 },                           // Token accounts only
      { memcmp: { offset: 0, base58: USDC_MINT } } // USDC only
      // Note: You'd implement balance filtering in your callback logic
    ]
  }
}