feat: allow spaces to be saved

Use lowdb to save spaces.

closes #42 #43

app/config/config.js

@@ -0,0 +1,42 @@
+// eslint-disable-next-line import/no-extraneous-dependencies
+const { app } = require('electron');
+
+// types that we support downloading
+const DOWNLOADABLE_MIME_TYPES = [
+  // video
+  'application/mp4',
+  'application/ogg',
+  'video/mp4',
+  'video/ogg',
+  'video/quicktime',
+  'video/webm',
+  // audio
+  'audio/mp4',
+  'audio/mpeg',
+  'audio/ogg',
+  'audio/webm',
+  'audio/x-aac',
+  'audio/x-wav',
+  // image
+  'image/bmp',
+  'image/gif',
+  'image/jpeg',
+  'image/png',
+  // pdf
+  'application/pdf',
+];
+
+// categories
+const RESOURCE = 'Resource';
+const APPLICATION = 'Application';
+
+const VAR_FOLDER = `${app.getPath('userData')}/var`;
+const DATABASE_PATH = `${VAR_FOLDER}/db.json`;
+
+module.exports = {
+  DOWNLOADABLE_MIME_TYPES,
+  RESOURCE,
+  APPLICATION,
+  DATABASE_PATH,
+  VAR_FOLDER,
+};

app/db.js

@@ -0,0 +1,38 @@
+const mkdirp = require('mkdirp');
+const low = require('lowdb');
+const fs = require('fs');
+const FileSync = require('lowdb/adapters/FileSync');
+const logger = require('./logger');
+const { DATABASE_PATH, VAR_FOLDER } = require('./config/config');
+
+// use promisified fs
+const fsPromises = fs.promises;
+
+// bootstrap database
+const ensureDatabaseExists = async (dbPath = DATABASE_PATH) => {
+  try {
+    await fsPromises.readFile(dbPath, { encoding: 'utf8' });
+  } catch (readErr) {
+    logger.error(readErr);
+    try {
+      mkdirp.sync(VAR_FOLDER);
+      await fsPromises.writeFile(dbPath, '');
+    } catch (writeErr) {
+      logger.error(writeErr);
+    }
+  }
+};
+
+const bootstrapDatabase = (dbPath = DATABASE_PATH) => {
+  const adapter = new FileSync(dbPath);
+  const db = low(adapter);
+
+  // set some defaults (required if json file is empty)
+  db.defaults({ spaces: [] }).write();
+  return db;
+};
+
+module.exports = {
+  ensureDatabaseExists,
+  bootstrapDatabase,
+};