eth-transaction-indexer

Tails transactions on the Ethereum blockchain and indexes them in a Hyperbee

npm install @hyperdivision/eth-transaction-indexer

Usage

const Indexer = require('eth-transaction-indexer')

const testnet = 'https://ropsten.infura.io/v3/2aa3f1f44c224eff83b07cef6a5b48b5'
const feed = hypercore('./path/to/storage')

// start indexing from block number
const beginAt = 0x899b00

const index = new Indexer(feed, {
  endpoint: testnet
})

// start the indexer
index.start()

// add an address to the index
index.add('0xdea..dbeef')

// get a stream of all the transactions paying to an address
const txns = index.createTransactionStream('0xdea..dbeef')

for await (let tx of txns) console.log(tx)

API

const index = new Indexer(feed, opts)

Instantiate a new index. Transactions of interest are logged in a Hyperbee written to the hypercore passed in as feed. endpoint should be an Ethereum HTTP API. defaultSeq gives the block number from which to start indexing from.

const opts = {
  endpoint: 'http://...',  // chain backend API
  defaultSeq: 9259777 // start from here if nothing has been stored. defaults to latest
}

index.start()

Start tailing the blockchain.

index.add(addr, [options])

Begin tracking transactions paying to addr. The initial balance of the address will be stored under the key !addr!<addr>, subsequent transactions will be added under the key !tx!<addr>!<block_number>!<tx_number>.

If you are tracking an ERC20 token, pass { token: <token-addr> } as well.

const str = index.createTransactionStream(addr)

Retrieve all transactions paying to the address given by addr. Returns an live stream of the time ordered transactions with the address' initial balance inserted before the first transaction.

The initial balance is inserted as a tx of the form:

{
  value: 0x4572e2,      // initial balance of the address
  blockNumber: 0x899b00 // block number at which the indexer began tracking the address
}

Other transactions are full eth transaction objects:

{
  blockHash: '0x277dfee78f6b1d8e495e7c25c95e0f2dc36a4ca772b32aa7b1ae7107f21d1351',
  blockNumber: '0x899f1b',
  from: '0x301b695ae7ba03b63828b6668232063bd4c9e0bc',
  gas: '0x5208',
  gasPrice: '0x7aef40a00',
  hash: '0x7cde8e856bf1c73146c64054f0e74acdd05d7ba351693c6aaeca620bcdcfc03e',
  input: '0x',
  nonce: '0x16',
  r: '0xf38ed059c881c3079d445081c09e6f0df7cfa5fa9be1cb830b479fbb1a0327c8',
  s: '0x63830c84ef2b177d9ec488eeb32215363364aa7aade743c403d2a06686b7fc95',
  to: '0x50c7d91e74b0e42bd8bce8ad6d199e4a23c0b193',
  transactionIndex: '0x0',
  v: '0x2a',
  value: '0x5af3107a4000'
}