Simple example on how to get accounts from state trie

printStateAccounts.js

const level = require('level')
const rlp = require('rlp')

const chaindatadirectory = './data_node_0/geth/chaindata'
const TX_ROOT_HASH    = '146d436eb3af4eeaf1f421d86a8994ef9f6e3670393837e9141f7f44b00e01cf'
const STATE_ROOT_HASH = '0c773fdbbe314cbeb0908d1b4949b39d1edca0653efee339882679538fce3318'

level(chaindatadirectory, { keyEncoding: 'utf8', valueEncoding: 'binary'}, async (err, db) => {
  if(err) {
    console.log('ERROR: ',err)
    return
  }

  const printData = async (triePath,root) => {
    if(!root || root.length == 0) return
    let data
    try {
      data = await db.get(root)
    } catch(err) {
      console.log(`ERROR getting data [${root.toString('hex')}]\n `)//,err)
      return
    }
    const dataBin = Buffer.from(data)
    const decodedRLP = rlp.decode(dataBin)
    //console.log("===============================================================================================================")
    //console.log(root)
    //console.log(decodedRLP)
    let nodeHash = []
    let value
    if(decodedRLP.length === 17) {
      nodeHash = decodedRLP.slice(0,16)
      value = decodedRLP[16].length ? decodedRLP[16] : null
    }
    if(decodedRLP.length === 2) {
      const firstNibble = decodedRLP[0][0] & 0xf0
      const secondNibble = decodedRLP[0][0] & 0x0f
      const isLeaf = (firstNibble === 0x20 || firstNibble === 0x30)
      const isOdd = (firstNibble === 0x10 || firstNibble === 0x30)
      let newAddrHash = decodedRLP[0].toString('hex')
      if(isOdd) newAddrHash = '0' + newAddrHash
      triePath = triePath.concat(newAddrHash.slice(2))
      if(isLeaf) {
        value = decodedRLP[1]
      } else {
        // TODO didn't test extentions, my db is not large enough
        nodeHash = decodedRLP[1]
      }
    }
    if(value) {
      const decodedValue = rlp.decode(value)
      const account = createAccount(triePath, decodedValue)
      try {
        const code = await db.get(decodedValue[3])
        account.code = code.toString('hex')
      } catch(err) {
        console.log(`ERROR getting code [${account.codeHash}]\n `)//,err)
      }
      //accounts.push(account)
      return account
    } else {
      const accounts = await Promise.all(nodeHash.map(async (h,idx) => {
        let newAddr = !(decodedRLP.length === 2) ? triePath + idx.toString(16) : triePath
        return h.length ? await printData(newAddr,h) : null
      }))
    return [].concat(...accounts).filter(acc => acc)
    }
  }

  const createAccount = (triePath, rlpDecodedValue) => ({
        addressHash: triePath,
        nonce:       rlpDecodedValue[0].toString('hex'),
        balance:     rlpDecodedValue[1].toString('hex'),
        storageRoot: rlpDecodedValue[2].toString('hex'),
        codeHash:    rlpDecodedValue[3].toString('hex'),
      })

  const root = new Buffer(STATE_ROOT_HASH, 'hex')
  const accounts = await printData('',root)
  console.log(">>>>>>>>>>>>>>>>>>>>>> <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<")
  console.log(">>>>>>>>>>>>>>>>>>>>>> <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<")
  console.log("All Accounts: ", JSON.stringify(accounts,4,4))


  // Example of how to get a block
  // const blockHash = Buffer.from('LastHeader')
  //const blockHash = Buffer.from('b815b580e518203367c6dda3302faf37fdcbcdcfdef6045a57715987c5d1183d6','hex')
  // const blockHash = Buffer.concat([Buffer.from('b'), Buffer.from('000000000000010d','hex'), Buffer.from('815b580e518203367c6dda3302faf37fdcbcdcfdef6045a57715987c5d1183d6','hex')])
  //const blockHash = Buffer.concat([Buffer.from('H'), Buffer.from('815b580e518203367c6dda3302faf37fdcbcdcfdef6045a57715987c5d1183d6','hex')])
  const createTransaction = (rlpDecodedValue) => {
    return {
      nonce: rlpDecodedValue[0],
      price: rlpDecodedValue[1],
      gasLimit: rlpDecodedValue[2],
      recipient: rlpDecodedValue[3],
      amount: rlpDecodedValue[4],
      payload: rlpDecodedValue[5],
      v: rlpDecodedValue[6],
      r: rlpDecodedValue[7],
      s: rlpDecodedValue[8],
    }
  }

  const getBlock = async (number,hash) => {
    const blockHash = Buffer.concat([
      Buffer.from('b'),
      Buffer.from(number.toString(16).padStart(16,0),'hex'),
      Buffer.from(hash,'hex')
    ])
    try {
      const data = await db.get(blockHash)
      const dataBin = Buffer.from(data)
      const decodedRLP = rlp.decode(dataBin)
      return { transactions: decodedRLP[0].map(d => createTransaction(d)), ommers: decodedRLP[1]}
    } catch(err) {
      console.log(`ERROR getting data [${blockHash.toString('hex')}]`,err)
      return
    }
  }

  console.log(await getBlock(154,'b70e0b9752c4127263ca831f7a6908f8f4ac5e9f6b5d7ee7d18e1a01e60d0ebe'))
})
// really good post on db details
// https://ethereum.stackexchange.com/a/57888/2688