@bigmi/core/src/transports/mempool/getTransactions.ts

TypeScript library for Bitcoin apps.

import type { UTXOTransaction } from '../../types/transaction.js'
import { urlWithParams } from '../../utils/url.js'
import type { RpcMethodHandler } from '../types.js'
import type {
  MempoolBalanceResponse,
  MempoolTransaction,
  MempoolUTXOTransactionsResponse,
} from './mempool.types.js'

const mempoolTransactionTransformer = (
  txn: MempoolTransaction
): Partial<UTXOTransaction> => ({
  hash: txn.txid,
  txid: txn.txid,
  vout: txn.vout.map((vout, index) => ({
    n: index,
    scriptPubKey: {
      address: vout.scriptpubkey_address,
      asm: vout.scriptpubkey_asm,
      type: vout.scriptpubkey_type,
      desc: vout.scriptpubkey,
      hex: vout.scriptpubkey,
    },
    value: vout.value,
  })),
  vin: txn.vin.map((vin) => ({
    scriptSig: {
      asm: vin.scriptsig_asm,
      hex: vin.scriptsig,
    },
    sequence: vin.sequence,
    txinwitness: vin.witness,
    txid: vin.txid,
    vout: vin.vout,
  })),
})

export const getTransactions: RpcMethodHandler<'getTransactions'> = async (
  client,
  { baseUrl },
  { address, limit = 50, offset = 0, afterTxId }
) => {
  const apiUrlAddress = `${baseUrl}/address/${address}`
  const balanceResponse = (await client.request({
    url: apiUrlAddress,
    fetchOptions: { method: 'GET' },
  })) as unknown as MempoolBalanceResponse
  const totalTxns =
    balanceResponse.chain_stats.tx_count +
    balanceResponse.mempool_stats.tx_count

  const apiUrl = urlWithParams(`${baseUrl}/address/${address}/txs`, {
    after_txid: afterTxId,
  })

  const response = (await client.request({
    url: apiUrl,
    fetchOptions: { method: 'GET' },
  })) as unknown as MempoolUTXOTransactionsResponse

  const transactions = response.map(mempoolTransactionTransformer)

  const result = {
    transactions,
    total: totalTxns,
    itemsPerPage: limit,
    hasMore: offset + transactions.length < totalTxns,
  }

  return {
    result,
  }
}