super-productivity/electron/backup.ts

import { app, ipcMain } from 'electron';
import { existsSync, mkdirSync, readdirSync, readFileSync, statSync, writeFileSync } from 'fs';
import { IPC } from './ipc-events.const';
import { answerRenderer } from './better-ipc';
import { LocalBackupMeta } from '../src/app/imex/local-backup/local-backup.model';
import * as path from 'path';

let BACKUP_DIR: string = `${app.getPath('userData')}/backups`;

export function initBackupAdapter(backupDir: string) {
  BACKUP_DIR = backupDir;
  console.log('Saving backups to', BACKUP_DIR);

  // BACKUP
  ipcMain.on(IPC.BACKUP, backupData);

  // IS_BACKUP_AVAILABLE
  answerRenderer(IPC.BACKUP_IS_AVAILABLE, (): LocalBackupMeta | false => {
    if (!existsSync(BACKUP_DIR)) {
      return false;
    }

    const files = readdirSync(BACKUP_DIR);
    if (!files.length) {
      return false;
    }
    const filesWithMeta: LocalBackupMeta[] = files.map((fileName: string): LocalBackupMeta => ({
      name: fileName,
      path: path.join(BACKUP_DIR, fileName),
      folder: BACKUP_DIR,
      created: statSync(path.join(BACKUP_DIR, fileName)).mtime.getTime()
    }));

    filesWithMeta.sort((a: LocalBackupMeta, b: LocalBackupMeta) => a.created - b.created);
    console.log('Avilable Backup Files: ', filesWithMeta);
    return filesWithMeta.reverse()[0];
  });

  // RESTORE_BACKUP
  answerRenderer(IPC.BACKUP_LOAD_DATA, (backupPath): string => {
    console.log('Reading backup file: ', backupPath);
    return readFileSync(backupPath, {encoding: 'utf8'});
  });
}

function backupData(ev, data) {
  if (!existsSync(BACKUP_DIR)) {
    mkdirSync(BACKUP_DIR);
  }
  const filePath = `${BACKUP_DIR}/${getDateStr()}.json`;

  try {
    const backup = JSON.stringify(data);
    writeFileSync(filePath, backup);
  } catch (e) {
    console.log('Error while backing up');
    console.error(e);
  }
}

function getDateStr(): string {
  const today = new Date();
  const dd = today.getDate();
  const mm = today.getMonth() + 1; // January is 0!
  const yyyy = today.getFullYear();

  const dds = (dd < 10)
    ? '0' + dd
    : dd.toString();
  const mms = (mm < 10)
    ? '0' + mm
    : mm.toString();
  return `${yyyy}-${mms}-${dds}`;
}