Read storage

Many important variable are available through the storage API. This example shows how to call a few of those APIs.

const Api = require('@polkadot/api').default
const WsProvider = require('@polkadot/api-provider/ws').default
const storage = require('@polkadot/storage').default
const BN = require('bn.js')

const provider = new WsProvider('ws://127.0.0.1:9944')
const api = new Api(provider)

async function getAccountIndex (address) {
  return api.state.getStorage([storage.system.public.accountIndexOf, address])
}

async function getValidators () {
  return api.state.getStorage([storage.session.public.validators])
}

async function getBlockPeriod () {
  return api.state.getStorage([storage.timestamp.public.blockPeriod])
}

async function main () {
  const address = '5GoKvZWG5ZPYL1WUovuHW3zJBWBP5eT8CbqjdRY4Q6iMaDtZ'
  const validators = await getValidators()
  const index = await getAccountIndex(address)
  const blockPeriod = await getBlockPeriod()

  console.log(`BlockPeriod: ${new BN(blockPeriod).toString(10)} seconds`)
  console.log(`Account Index of ${address}: ${index.toString(10)}`)
  console.log('Current validators', validators)
}

main().finally(_ => process.exit())