@lsdsoftware/s3-log-store/src/work-dir.test.ts

Efficiently store and retrieve log-structured data (append only) in S3

import { describe, expect } from "@service-broker/test-utils";
import fsp from "fs/promises";
import os from "os";
import path from "path";
import { makeWorkDir } from "./work-dir.js";


describe('work-dir', ({ beforeEach, afterEach, test }) => {
  let workDirPath: string
  let workDir: ReturnType<typeof makeWorkDir>

  beforeEach(async () => {
    workDirPath = path.join(os.tmpdir(), "s3logstore-testworkdir-" + Math.random().toString(36).slice(2))
    await fsp.mkdir(workDirPath)
    workDir = makeWorkDir(workDirPath)
  })

  afterEach(async () => {
    await fsp.rm(workDirPath, { recursive: true })
  })

  test('ensureEmpty', async () => {
    await workDir.ensureEmpty()
    await fsp.writeFile(path.join(workDirPath, 'dummy'), 'dummy')
    await workDir.ensureEmpty()
      .then(
        () => { throw new Error('!throwAsExpected') },
        err => expect(err.message, 'Workdir not empty as expected')
      )
  })

  test('listChanges', async () => {
    await fsp.writeFile(path.join(workDirPath, 'before'), 'before')
    await new Promise(f => setTimeout(f, 100))
    await fsp.writeFile(path.join(workDirPath, 'checkpoint'), 'checkpoint')
    await new Promise(f => setTimeout(f, 100))
    await fsp.writeFile(path.join(workDirPath, 'after'), 'after')
    expect(await workDir.listChanges(path.join(workDirPath, 'checkpoint')), ['after'])
  })

  test('deleteInactive', async () => {
    const now = Date.now()
    const twentyFourHoursAgo = now - 24*3600_000

    const inactivePath = path.join(workDirPath, 'inactive')
    await fsp.writeFile(inactivePath, 'inactive')
    await fsp.utimes(inactivePath, new Date(now), new Date(twentyFourHoursAgo - 10_000))

    const activePath = path.join(workDirPath, 'active')
    await fsp.writeFile(activePath, 'active')
    await fsp.utimes(activePath, new Date(now), new Date(twentyFourHoursAgo + 10_000))

    await workDir.deleteInactive(1)
    expect(await fsp.readdir(workDirPath), ['active'])
  })

  test('makeWorkFile', async () => {
    const workFile = workDir.makeWorkFile('first')
    await workFile.append('line1\nline2\n')
    expect(await workFile.read(), { payload: 'line1\nline2\n' })

    await workFile.write(11, 'line3\nline4\n')
    await workFile.append('line5\n')
    expect(await workFile.read(), { header: { seqNum: 11 }, payload: 'line3\nline4\nline5\n' })
  })
})