Slack private messages history export

analyze-stat.js

const msgs = require('./history.json')

const data = {}
const usersObj = {}
for (const msg of msgs) {
  const msgTs = new Date(parseFloat(msg.ts) * 1000)
  const ts = new Date(msgTs.getFullYear(), msgTs.getMonth(), msgTs.getDate())
  const key = `${ts.getFullYear()}/${ts.getMonth()+1}/${ts.getDate()}`
  if (!data[key]) data[key] = { key, ts }

  usersObj[msg.user] = true
  if (!data[key][msg.user]) data[key][msg.user] = 1
  else data[key][msg.user] += 1
}

const users = Object.keys(usersObj)
process.stdout.write('date')
for (const user of users) process.stdout.write(';' + user)
process.stdout.write('\n')

for (const item of Object.values(data).sort((a, b) => a.valueOf() < b.valueOf())) {
  process.stdout.write(item.key)
  for (const user of users) process.stdout.write(';' + (item[user] || 0))
  process.stdout.write('\n')
}

export.js

const fs = require('fs')
const fetch = require('node-fetch')

const token = 'xoxp-...'
const channel = '...'

async function getHistory (oldest) {
  const count = 1000
  const url = `https://slack.com/api/conversations.history?token=${token}&channel=${channel}&count=${count}&oldest=${oldest}`
  const res = await fetch(url)
  return res.json()
}

;(async () => {
  const history = []

  let oldest = 1
  while (true) {
    const data = await getHistory(oldest)
    const fromTs = new Date(parseFloat(data.messages[data.messages.length - 1].ts) * 1000)
    const toTs = new Date(parseFloat(data.messages[0].ts) * 1000)
    console.log(`received ${data.messages.length} messages, ${fromTs} => ${toTs}`)

    oldest = data.messages[0].ts
    history.push(...data.messages.reverse())
    if (!data.has_more) break

    await new Promise((resolve) => setTimeout(resolve, 1500))
  }

  fs.writeFileSync('./history.json', JSON.stringify(history))
})().catch((err) => {
  console.log(err.stack || err)
  process.exit(1)
})