DB size code

dbSize.js

(function showIndexedDbSize() {
  'use strict';
  var db;
  var storesizes = new Array();

  function openDatabase(dbname) {
    return new Promise(function(resolve, reject) {
      var request = window.indexedDB.open(dbname);
      request.onsuccess = function(event) {
        db = event.target.result;
        resolve(db.objectStoreNames);
      };
    });
  }

  function getObjectStoreData(storename) {
    return new Promise(function(resolve, reject) {
      var trans = db.transaction(storename, IDBTransaction.READ_ONLY);
      var store = trans.objectStore(storename);
      var items = [];
      trans.oncomplete = function(evt) {
        var szBytes = toSize(items);
        var szMBytes = (szBytes / 1024 / 1024).toFixed(2);
        storesizes.push({
          'Store Name': storename,
          'Items': items.length,
          'Size': szMBytes + 'MB (' + szBytes + ' bytes)',
        });
        resolve();
      };
      var cursorRequest = store.openCursor();
      cursorRequest.onerror = function(error) {
        reject(error);
      };
      cursorRequest.onsuccess = function(evt) {
        var cursor = evt.target.result;
        if (cursor) {
          items.push(cursor.value);
          cursor.continue();
        }
      };
    });
  }

  function toSize(items) {
    var size = 0;
    for (var i = 0; i < items.length; i++) {
      var objectSize = JSON.stringify(items[i]).length;
      size += objectSize * 2;
    }
    return size;
  }

  function process(stores) {
    var PromiseArray = [];
    for (var i = 0; i < stores.length; i++) {
      PromiseArray.push(getObjectStoreData(stores[i]));
    }
    Promise.all(PromiseArray).then(function() {
      console.table(storesizes);
    });
  }

  openDatabase('./data').then(process);
  openDatabase('data/blocks').then(process);
  openDatabase('data/datastore').then(process);
  openDatabase('data/keys').then(process);
  openDatabase('0x-mesh-db').then(process);
}());