gzip_data.js

// @ts-check
import { generate } from '@mapeo/mock-data'
import { encode } from '@mapeo/schema'
import Hypercore from 'hypercore'
import RAM from 'random-access-memory'
import { gzipSync } from 'zlib'


/**
 * @param {ReadonlyArray<any>} records
 * @returns {Promise<number>}
 */
const getUncompressedSize = async (records) => {
  const ram = new RAM()

  const hypercore = new Hypercore(() => ram)
  await hypercore.ready()

  await Promise.all(records.map((record) => hypercore.append(encode(record))))

  return ram.toBuffer().byteLength
}

/**
 * @param {ReadonlyArray<any>} records
 * @returns {Promise<number>}
 */
const getCompressedSize = async (records) => {
  const ram = new RAM()

  const hypercore = new Hypercore(() => ram)
  await hypercore.ready()

  await Promise.all(records.map((record) => hypercore.append(encode(record))))

  const uncompressedBuffer = ram.toBuffer()

  return gzipSync(uncompressedBuffer, { level: 9 }).byteLength
}

const main = async () => {
  const records = [
    ...generate('projectSettings', { count: 100 }),
    ...generate('observation', { count: 10_000 }),
    ...generate('field', { count: 1000 }),
    ...generate('preset', { count: 1000 }),
    ...generate('role', { count: 100 }),
    ...generate('deviceInfo', { count: 100 }),
    // `translation` and `track` are missing from `@mapeo/mock-data`
    // `icon` and `coreOwnership` had issues I did not investigate
  ]

  console.log('Record count:', records.length)

  const uncompressedSize = await getUncompressedSize(records)
  console.log('Uncompressed size:', uncompressedSize)

  const compressedSize = await getCompressedSize(records)
  console.log('Compressed size:', compressedSize)
}

main().catch((err) => {
  console.error(err)
  process.exit(1)
})