Magic Eden On-Chain Transaction Parsing

magicEdenParser.js

const solanaWeb3 = require('@solana/web3.js');

// replace with private paid RPC for best functionality
const rpc = "https://ssc-dao.genesysgo.net";
// magic eden v2 solana program ID
const magicEdenPID = new solanaWeb3.PublicKey("M2mx93ekt1fmXSVkTrUL9xVFHkmME8HTUi5Cyc5aF7K");
// only return confirmed transactions
const solana = new solanaWeb3.Connection(rpc, 'confirmed');

/**
 * Given a transaction and a type, extract specific addresses
 * @param {Object} tx - the transaction returned from the rpc
 * @param {string} txType - string for type switch case
 * @returns {Object | null} - needed addresses from tx or null if unrecognized txType
 */
function parseAccounts(tx, txType) {
    const accounts = tx.transaction.message.accountKeys;
    switch (txType) {
        case 'buy':
            return {
                buyer: accounts[0],
                seller: accounts[4],
                token: accounts[11]
            }
        case 'sell':
            return {
                seller: accounts[0],
                buyer: accounts[4],
                token: accounts[11]
            }
        case 'list':
            return {
                seller: accounts[0],
                token: accounts[4],
            }
        case 'update':
            return {
                seller: accounts[0],
                token: accounts[4],
            }
        case 'delist':
            return {
                seller: accounts[0],
                token: accounts[5],
            }
        default:
            return null;
    }
}

/**
 * Classify and parse a transaction from the Solana RPC
 *
 * @param {Object} tx - the transaction object returned from the solana RPC
 * @return {Object} - formatted tx classification & data extracted from RPC response
 */
function parseTransaction(tx) {
    const logs = tx.meta.logMessages;
    const instructions = logs.filter(log => log.includes("Instruction"));
    const price = JSON.parse(logs.filter(log => log.includes("price"))[0].slice(13)).price;
    let txType = null;
    if (instructions.filter(entry => entry.includes("ExecuteSale")).length != 0) {
        /* If instruction includes 'ExecuteSale' determine if buyer or seller executed */
        if (instructions.filter(entry => entry.includes("Buy")).length != 0)
            txType = "buy";
        else
            txType = "sell";
    } else if (instructions.filter(entry => entry.includes(" Sell")).length != 0) {
        /* If instruction is not a sale and includes 'sell' determine if initial listing or listing update */
        // @notice needs a more robust decoding feature - will fail with custom instruction sequences
        if (logs.length == 5)
            txType = "update";
        else
            txType = "list";
    } else if (instructions.filter(entry => entry.includes("CancelSell")).length != 0)
        /* Instruction delists token from exchange */
        txType = "delist";
    if (txType !== null) return {
        /* Instruction is not recognized */
        // @notice purposely ignoring bids and cancel bids. Can easily be added with same scheme as above
        txType,
        price,
        ...parseAccounts(tx, txType)
    };
    else return null;
}

/**
 * Get the last 1000 transactions from Magic Eden Solana Program on-chain and parse them
 * @return {Object[]} - array of parsed transactions
 */
async function main() {
    const signatures = await solana.getSignaturesForAddress(magicEdenPID);
    return await Promise.all(
        signatures.map(sig => new Promise(async (resolve, reject) => {
            try {
                solana.getTransaction(signatures[0].signature)
                    .then(res => parseTransaction(res))
                    .then(res => resolve(res));
            } catch (e) {
                reject(e)
            }
        }))
    );
}

main().then(console.log);

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