indexedDb.api.js

const DEFAULT_IONIC_DB = '_ionicstorage';
const DEFAULT_IONIC_TABLE = '_ionickv';
let db;
function setupIndexedDb() {
  return new Promise((resolve, reject) => {
    if (!indexedDB) {
      return reject(new Error('indexedDB not suported'));
    }
    if (db) {
      return resolve(db);
    }
    const request = indexedDB.open(DEFAULT_IONIC_DB);
    request.onsuccess = () => {
      db = request.result;
      console.log('OPEN');
      return resolve(db);
    };
    request.onupgradeneeded = () => {
      db = request.result;
      const table = db.createObjectStore(DEFAULT_IONIC_TABLE);
      console.log('CREATED');
      return resolve(db);
    };
    request.onerror = error => {
      console.log('error indexedDb');
      return reject(error);
    };
    return undefined;
  });
}

export function set(key, data) {
  return setupIndexedDb().then(database => {
    return new Promise((resolve, reject) => {
      const transaction = database.transaction(
        DEFAULT_IONIC_TABLE,
        'readwrite',
      );
      const objectStore = transaction.objectStore(DEFAULT_IONIC_TABLE);
      const setRequest = objectStore.add(data, key);
      setRequest.onsuccess = () => {
        return resolve('data saved');
      };
      setRequest.onerror = error => {
        return reject(error);
      };
    });
  });
}

export function get(key) {
  return setupIndexedDb().then(database => {
    return new Promise((resolve, reject) => {
      const transaction = database.transaction(DEFAULT_IONIC_TABLE, 'readonly');
      const objectStore = transaction.objectStore(DEFAULT_IONIC_TABLE);
      const getRequest = objectStore.get(key);
      getRequest.onsuccess = data => {
        return resolve(data?.target?.result);
      };
      getRequest.onerror = error => {
        return reject(error);
      };
    });
  });
}