hypercore-progress

Track the sync progress of a non-sparse non-live hypercore replication stream.

This module lets you wrap a hypercore

N.B. Designed for hypercore@8

N.B. This should give accurate download and upload progress when sparse mode is off. However, when using sparse mode, download progress should remain accurate, but upload progress can be inaccurate. This is due to how the hypercore protocol works: the remote peer doesn't have to explicitly name the blocks it wants -- it can provide a range of wants that may include blocks it already possesses. Live streams aren't yet supported either.

Usage

var progress = require('hypercore-progress')
var ram = require('random-access-memory')
var hypercore = require('hypercore')
var pump = require('pump')

var core1 = hypercore(ram, {valueEncoding:'json'})
core1.ready(() => {
  core1.append([
    'ichi',
    'ni',
    'san',
  ], () => {
    var core2 = hypercore(ram, core1.key, {valueEncoding:'json'})
    core2.ready(() => {
      sync()
    })
  })
})

function sync () {
  var r1 = core1.replicate(true)
  progress(core1, r1).on('progress', (status) => {
    console.log('core1', status)
  })

  var r2 = core2.replicate(false)
  progress(core2, r2).on('progress', (status) => {
    console.log('core1', status)
  })

  pump(r1, r2, r1, err => {
    console.log('done')
  })
})

outputs

core1 { up: { sofar: 1, total: 3 }, down: { sofar: 0, total: 0 } }
core2 { up: { sofar: 0, total: 0 }, down: { sofar: 1, total: 3 } }
core1 { up: { sofar: 2, total: 3 }, down: { sofar: 0, total: 0 } }
core2 { up: { sofar: 0, total: 0 }, down: { sofar: 2, total: 3 } }
core1 { up: { sofar: 3, total: 3 }, down: { sofar: 0, total: 0 } }
core2 { up: { sofar: 0, total: 0 }, down: { sofar: 3, total: 3 } }
done

API

var progress = require('hypercore-progress')

var tracker = progress(feed, stream)

Wraps a hypercore and a particular hypercore-protocol stream and tracks upload and download progress of the hypercores it is replicating.

tracker.on('progress', (state) => {})

Emitted when a chunk is downloaded or uploaded.

state will be of the shape

{
  up: { sofar: 5, total: 12 },
  down: { sofar: 1, total: 3 }
}

Install

With npm installed, run

$ npm install hypercore-progress

Caveats

This module makes some assumptions:

1. "live" replication mode is not being used
2. "sparse" replication mode is not being used

License

MIT