@hyperdivision/btc-transaction-tail

Tails transactions on the Bitcoin blockchain

npm install @hyperdivision/btc-transaction-tail

Usage

const Tail = require('@hyperdivision/btc-transaction-tail')

const tail = new Tail({
  confirmations: 10, // require this many confirmations
  async filter (addr) {
    return isInterestingAddress(addr)
  },
  async transaction (transaction) {
    console.log('found this transaction', transaction)
  },
  async checkpoint (since) {
    // store this since so you can restart from here
  },
  async reorganize (since) {
    // all transactions/blocks with blockNumber >= since have been
    // reorganized
  }
})

;(async function () {
  // tail.index is the current block index
  // tail chain since this seq (inclusive)
  await tail.start() // start tailing, will throw if an error is hit
  await tail.scan(424244)
})().catch(console.error)

API

const tail = new Tail(opts)

{
  network: 'main',
  confirmations: 0,
  prefix: null, // Where to store chain data
  // direction can be either IN or OUT symbol
  async filter (addressString, direction) { return true },
  async transaction (bcoin.TX) { },
  async checkpoint (blockHeight) { },
  async reorganize (blockHeight) {}
  // Pass options directly to bcoin FullNode
  // May overwrite some of the previous opts
  bcoin: {}
}

Tail.IN

Signals a transaction that has a filtered address in the inputs

Tail.OUT

Signals a transaction that has a filtered address in the output

tail.start()

tail.scan(since = 0)

tail.stop()

tail.on('mempool-add', tx)

Emitted when a transaction is added to the mempool

tail.on('mempool-remove', tx)

Emitted when a transaction is removed from the mempool