react-localforage/dist/react-localforage.es.js

Declarative localForage in React

import React from 'react';
import PropTypes from 'prop-types';

function commonjsRequire () {
	throw new Error('Dynamic requires are not currently supported by rollup-plugin-commonjs');
}



function createCommonjsModule(fn, module) {
	return module = { exports: {} }, fn(module, module.exports), module.exports;
}

var localforage = createCommonjsModule(function (module, exports) {
/*!
    localForage -- Offline Storage, Improved
    Version 1.5.0
    https://localforage.github.io/localForage
    (c) 2013-2017 Mozilla, Apache License 2.0
*/
(function(f){{module.exports=f();}})(function(){var define,module,exports;return (function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof commonjsRequire=="function"&&commonjsRequire;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw (f.code="MODULE_NOT_FOUND", f)}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r);}return n[o].exports}var i=typeof commonjsRequire=="function"&&commonjsRequire;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(_dereq_,module,exports){
(function (global){
'use strict';
var Mutation = global.MutationObserver || global.WebKitMutationObserver;

var scheduleDrain;

{
  if (Mutation) {
    var called = 0;
    var observer = new Mutation(nextTick);
    var element = global.document.createTextNode('');
    observer.observe(element, {
      characterData: true
    });
    scheduleDrain = function () {
      element.data = (called = ++called % 2);
    };
  } else if (!global.setImmediate && typeof global.MessageChannel !== 'undefined') {
    var channel = new global.MessageChannel();
    channel.port1.onmessage = nextTick;
    scheduleDrain = function () {
      channel.port2.postMessage(0);
    };
  } else if ('document' in global && 'onreadystatechange' in global.document.createElement('script')) {
    scheduleDrain = function () {

      // Create a <script> element; its readystatechange event will be fired asynchronously once it is inserted
      // into the document. Do so, thus queuing up the task. Remember to clean up once it's been called.
      var scriptEl = global.document.createElement('script');
      scriptEl.onreadystatechange = function () {
        nextTick();

        scriptEl.onreadystatechange = null;
        scriptEl.parentNode.removeChild(scriptEl);
        scriptEl = null;
      };
      global.document.documentElement.appendChild(scriptEl);
    };
  } else {
    scheduleDrain = function () {
      setTimeout(nextTick, 0);
    };
  }
}

var draining;
var queue = [];
//named nextTick for less confusing stack traces
function nextTick() {
  draining = true;
  var i, oldQueue;
  var len = queue.length;
  while (len) {
    oldQueue = queue;
    queue = [];
    i = -1;
    while (++i < len) {
      oldQueue[i]();
    }
    len = queue.length;
  }
  draining = false;
}

module.exports = immediate;
function immediate(task) {
  if (queue.push(task) === 1 && !draining) {
    scheduleDrain();
  }
}

}).call(this,typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {});
},{}],2:[function(_dereq_,module,exports){
'use strict';
var immediate = _dereq_(1);

/* istanbul ignore next */
function INTERNAL() {}

var handlers = {};

var REJECTED = ['REJECTED'];
var FULFILLED = ['FULFILLED'];
var PENDING = ['PENDING'];

module.exports = exports = Promise;

function Promise(resolver) {
  if (typeof resolver !== 'function') {
    throw new TypeError('resolver must be a function');
  }
  this.state = PENDING;
  this.queue = [];
  this.outcome = void 0;
  if (resolver !== INTERNAL) {
    safelyResolveThenable(this, resolver);
  }
}

Promise.prototype["catch"] = function (onRejected) {
  return this.then(null, onRejected);
};
Promise.prototype.then = function (onFulfilled, onRejected) {
  if (typeof onFulfilled !== 'function' && this.state === FULFILLED ||
    typeof onRejected !== 'function' && this.state === REJECTED) {
    return this;
  }
  var promise = new this.constructor(INTERNAL);
  if (this.state !== PENDING) {
    var resolver = this.state === FULFILLED ? onFulfilled : onRejected;
    unwrap(promise, resolver, this.outcome);
  } else {
    this.queue.push(new QueueItem(promise, onFulfilled, onRejected));
  }

  return promise;
};
function QueueItem(promise, onFulfilled, onRejected) {
  this.promise = promise;
  if (typeof onFulfilled === 'function') {
    this.onFulfilled = onFulfilled;
    this.callFulfilled = this.otherCallFulfilled;
  }
  if (typeof onRejected === 'function') {
    this.onRejected = onRejected;
    this.callRejected = this.otherCallRejected;
  }
}
QueueItem.prototype.callFulfilled = function (value) {
  handlers.resolve(this.promise, value);
};
QueueItem.prototype.otherCallFulfilled = function (value) {
  unwrap(this.promise, this.onFulfilled, value);
};
QueueItem.prototype.callRejected = function (value) {
  handlers.reject(this.promise, value);
};
QueueItem.prototype.otherCallRejected = function (value) {
  unwrap(this.promise, this.onRejected, value);
};

function unwrap(promise, func, value) {
  immediate(function () {
    var returnValue;
    try {
      returnValue = func(value);
    } catch (e) {
      return handlers.reject(promise, e);
    }
    if (returnValue === promise) {
      handlers.reject(promise, new TypeError('Cannot resolve promise with itself'));
    } else {
      handlers.resolve(promise, returnValue);
    }
  });
}

handlers.resolve = function (self, value) {
  var result = tryCatch(getThen, value);
  if (result.status === 'error') {
    return handlers.reject(self, result.value);
  }
  var thenable = result.value;

  if (thenable) {
    safelyResolveThenable(self, thenable);
  } else {
    self.state = FULFILLED;
    self.outcome = value;
    var i = -1;
    var len = self.queue.length;
    while (++i < len) {
      self.queue[i].callFulfilled(value);
    }
  }
  return self;
};
handlers.reject = function (self, error) {
  self.state = REJECTED;
  self.outcome = error;
  var i = -1;
  var len = self.queue.length;
  while (++i < len) {
    self.queue[i].callRejected(error);
  }
  return self;
};

function getThen(obj) {
  // Make sure we only access the accessor once as required by the spec
  var then = obj && obj.then;
  if (obj && typeof obj === 'object' && typeof then === 'function') {
    return function appyThen() {
      then.apply(obj, arguments);
    };
  }
}

function safelyResolveThenable(self, thenable) {
  // Either fulfill, reject or reject with error
  var called = false;
  function onError(value) {
    if (called) {
      return;
    }
    called = true;
    handlers.reject(self, value);
  }

  function onSuccess(value) {
    if (called) {
      return;
    }
    called = true;
    handlers.resolve(self, value);
  }

  function tryToUnwrap() {
    thenable(onSuccess, onError);
  }

  var result = tryCatch(tryToUnwrap);
  if (result.status === 'error') {
    onError(result.value);
  }
}

function tryCatch(func, value) {
  var out = {};
  try {
    out.value = func(value);
    out.status = 'success';
  } catch (e) {
    out.status = 'error';
    out.value = e;
  }
  return out;
}

exports.resolve = resolve;
function resolve(value) {
  if (value instanceof this) {
    return value;
  }
  return handlers.resolve(new this(INTERNAL), value);
}

exports.reject = reject;
function reject(reason) {
  var promise = new this(INTERNAL);
  return handlers.reject(promise, reason);
}

exports.all = all;
function all(iterable) {
  var self = this;
  if (Object.prototype.toString.call(iterable) !== '[object Array]') {
    return this.reject(new TypeError('must be an array'));
  }

  var len = iterable.length;
  var called = false;
  if (!len) {
    return this.resolve([]);
  }

  var values = new Array(len);
  var resolved = 0;
  var i = -1;
  var promise = new this(INTERNAL);

  while (++i < len) {
    allResolver(iterable[i], i);
  }
  return promise;
  function allResolver(value, i) {
    self.resolve(value).then(resolveFromAll, function (error) {
      if (!called) {
        called = true;
        handlers.reject(promise, error);
      }
    });
    function resolveFromAll(outValue) {
      values[i] = outValue;
      if (++resolved === len && !called) {
        called = true;
        handlers.resolve(promise, values);
      }
    }
  }
}

exports.race = race;
function race(iterable) {
  var self = this;
  if (Object.prototype.toString.call(iterable) !== '[object Array]') {
    return this.reject(new TypeError('must be an array'));
  }

  var len = iterable.length;
  var called = false;
  if (!len) {
    return this.resolve([]);
  }

  var i = -1;
  var promise = new this(INTERNAL);

  while (++i < len) {
    resolver(iterable[i]);
  }
  return promise;
  function resolver(value) {
    self.resolve(value).then(function (response) {
      if (!called) {
        called = true;
        handlers.resolve(promise, response);
      }
    }, function (error) {
      if (!called) {
        called = true;
        handlers.reject(promise, error);
      }
    });
  }
}

},{"1":1}],3:[function(_dereq_,module,exports){
(function (global){
'use strict';
if (typeof global.Promise !== 'function') {
  global.Promise = _dereq_(2);
}

}).call(this,typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {});
},{"2":2}],4:[function(_dereq_,module,exports){
'use strict';

var _typeof = typeof Symbol === "function" && typeof Symbol.iterator === "symbol" ? function (obj) { return typeof obj; } : function (obj) { return obj && typeof Symbol === "function" && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj; };

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

function getIDB() {
    /* global indexedDB,webkitIndexedDB,mozIndexedDB,OIndexedDB,msIndexedDB */
    try {
        if (typeof indexedDB !== 'undefined') {
            return indexedDB;
        }
        if (typeof webkitIndexedDB !== 'undefined') {
            return webkitIndexedDB;
        }
        if (typeof mozIndexedDB !== 'undefined') {
            return mozIndexedDB;
        }
        if (typeof OIndexedDB !== 'undefined') {
            return OIndexedDB;
        }
        if (typeof msIndexedDB !== 'undefined') {
            return msIndexedDB;
        }
    } catch (e) {}
}

var idb = getIDB();

function isIndexedDBValid() {
    try {
        // Initialize IndexedDB; fall back to vendor-prefixed versions
        // if needed.
        if (!idb) {
            return false;
        }
        // We mimic PouchDB here;
        //
        // We test for openDatabase because IE Mobile identifies itself
        // as Safari. Oh the lulz...
        var isSafari = typeof openDatabase !== 'undefined' && /(Safari|iPhone|iPad|iPod)/.test(navigator.userAgent) && !/Chrome/.test(navigator.userAgent) && !/BlackBerry/.test(navigator.platform);

        var hasFetch = typeof fetch === 'function' && fetch.toString().indexOf('[native code') !== -1;

        // Safari <10.1 does not meet our requirements for IDB support (#5572)
        // since Safari 10.1 shipped with fetch, we can use that to detect it
        return (!isSafari || hasFetch) && typeof indexedDB !== 'undefined' &&
        // some outdated implementations of IDB that appear on Samsung
        // and HTC Android devices <4.4 are missing IDBKeyRange
        typeof IDBKeyRange !== 'undefined';
    } catch (e) {
        return false;
    }
}

function isWebSQLValid() {
    return typeof openDatabase === 'function';
}

function isLocalStorageValid() {
    try {
        return typeof localStorage !== 'undefined' && 'setItem' in localStorage && localStorage.setItem;
    } catch (e) {
        return false;
    }
}

// Abstracts constructing a Blob object, so it also works in older
// browsers that don't support the native Blob constructor. (i.e.
// old QtWebKit versions, at least).
// Abstracts constructing a Blob object, so it also works in older
// browsers that don't support the native Blob constructor. (i.e.
// old QtWebKit versions, at least).
function createBlob(parts, properties) {
    /* global BlobBuilder,MSBlobBuilder,MozBlobBuilder,WebKitBlobBuilder */
    parts = parts || [];
    properties = properties || {};
    try {
        return new Blob(parts, properties);
    } catch (e) {
        if (e.name !== 'TypeError') {
            throw e;
        }
        var Builder = typeof BlobBuilder !== 'undefined' ? BlobBuilder : typeof MSBlobBuilder !== 'undefined' ? MSBlobBuilder : typeof MozBlobBuilder !== 'undefined' ? MozBlobBuilder : WebKitBlobBuilder;
        var builder = new Builder();
        for (var i = 0; i < parts.length; i += 1) {
            builder.append(parts[i]);
        }
        return builder.getBlob(properties.type);
    }
}

// This is CommonJS because lie is an external dependency, so Rollup
// can just ignore it.
if (typeof Promise === 'undefined') {
    // In the "nopromises" build this will just throw if you don't have
    // a global promise object, but it would throw anyway later.
    _dereq_(3);
}
var Promise$1 = Promise;

function executeCallback(promise, callback) {
    if (callback) {
        promise.then(function (result) {
            callback(null, result);
        }, function (error) {
            callback(error);
        });
    }
}

function executeTwoCallbacks(promise, callback, errorCallback) {
    if (typeof callback === 'function') {
        promise.then(callback);
    }

    if (typeof errorCallback === 'function') {
        promise["catch"](errorCallback);
    }
}

// Some code originally from async_storage.js in
// [Gaia](https://github.com/mozilla-b2g/gaia).

var DETECT_BLOB_SUPPORT_STORE = 'local-forage-detect-blob-support';
var supportsBlobs;
var dbContexts;
var toString = Object.prototype.toString;

// Transform a binary string to an array buffer, because otherwise
// weird stuff happens when you try to work with the binary string directly.
// It is known.
// From http://stackoverflow.com/questions/14967647/ (continues on next line)
// encode-decode-image-with-base64-breaks-image (2013-04-21)
function _binStringToArrayBuffer(bin) {
    var length = bin.length;
    var buf = new ArrayBuffer(length);
    var arr = new Uint8Array(buf);
    for (var i = 0; i < length; i++) {
        arr[i] = bin.charCodeAt(i);
    }
    return buf;
}

//
// Blobs are not supported in all versions of IndexedDB, notably
// Chrome <37 and Android <5. In those versions, storing a blob will throw.
//
// Various other blob bugs exist in Chrome v37-42 (inclusive).
// Detecting them is expensive and confusing to users, and Chrome 37-42
// is at very low usage worldwide, so we do a hacky userAgent check instead.
//
// content-type bug: https://code.google.com/p/chromium/issues/detail?id=408120
// 404 bug: https://code.google.com/p/chromium/issues/detail?id=447916
// FileReader bug: https://code.google.com/p/chromium/issues/detail?id=447836
//
// Code borrowed from PouchDB. See:
// https://github.com/pouchdb/pouchdb/blob/master/packages/node_modules/pouchdb-adapter-idb/src/blobSupport.js
//
function _checkBlobSupportWithoutCaching(idb) {
    return new Promise$1(function (resolve) {
        var txn = idb.transaction(DETECT_BLOB_SUPPORT_STORE, 'readwrite');
        var blob = createBlob(['']);
        txn.objectStore(DETECT_BLOB_SUPPORT_STORE).put(blob, 'key');

        txn.onabort = function (e) {
            // If the transaction aborts now its due to not being able to
            // write to the database, likely due to the disk being full
            e.preventDefault();
            e.stopPropagation();
            resolve(false);
        };

        txn.oncomplete = function () {
            var matchedChrome = navigator.userAgent.match(/Chrome\/(\d+)/);
            var matchedEdge = navigator.userAgent.match(/Edge\//);
            // MS Edge pretends to be Chrome 42:
            // https://msdn.microsoft.com/en-us/library/hh869301%28v=vs.85%29.aspx
            resolve(matchedEdge || !matchedChrome || parseInt(matchedChrome[1], 10) >= 43);
        };
    })["catch"](function () {
        return false; // error, so assume unsupported
    });
}

function _checkBlobSupport(idb) {
    if (typeof supportsBlobs === 'boolean') {
        return Promise$1.resolve(supportsBlobs);
    }
    return _checkBlobSupportWithoutCaching(idb).then(function (value) {
        supportsBlobs = value;
        return supportsBlobs;
    });
}

function _deferReadiness(dbInfo) {
    var dbContext = dbContexts[dbInfo.name];

    // Create a deferred object representing the current database operation.
    var deferredOperation = {};

    deferredOperation.promise = new Promise$1(function (resolve) {
        deferredOperation.resolve = resolve;
    });

    // Enqueue the deferred operation.
    dbContext.deferredOperations.push(deferredOperation);

    // Chain its promise to the database readiness.
    if (!dbContext.dbReady) {
        dbContext.dbReady = deferredOperation.promise;
    } else {
        dbContext.dbReady = dbContext.dbReady.then(function () {
            return deferredOperation.promise;
        });
    }
}

function _advanceReadiness(dbInfo) {
    var dbContext = dbContexts[dbInfo.name];

    // Dequeue a deferred operation.
    var deferredOperation = dbContext.deferredOperations.pop();

    // Resolve its promise (which is part of the database readiness
    // chain of promises).
    if (deferredOperation) {
        deferredOperation.resolve();
    }
}

function _getConnection(dbInfo, upgradeNeeded) {
    return new Promise$1(function (resolve, reject) {

        if (dbInfo.db) {
            if (upgradeNeeded) {
                _deferReadiness(dbInfo);
                dbInfo.db.close();
            } else {
                return resolve(dbInfo.db);
            }
        }

        var dbArgs = [dbInfo.name];

        if (upgradeNeeded) {
            dbArgs.push(dbInfo.version);
        }

        var openreq = idb.open.apply(idb, dbArgs);

        if (upgradeNeeded) {
            openreq.onupgradeneeded = function (e) {
                var db = openreq.result;
                try {
                    db.createObjectStore(dbInfo.storeName);
                    if (e.oldVersion <= 1) {
                        // Added when support for blob shims was added
                        db.createObjectStore(DETECT_BLOB_SUPPORT_STORE);
                    }
                } catch (ex) {
                    if (ex.name === 'ConstraintError') {
                        console.warn('The database "' + dbInfo.name + '"' + ' has been upgraded from version ' + e.oldVersion + ' to version ' + e.newVersion + ', but the storage "' + dbInfo.storeName + '" already exists.');
                    } else {
                        throw ex;
                    }
                }
            };
        }

        openreq.onerror = function (e) {
            e.preventDefault();
            reject(openreq.error);
        };

        openreq.onsuccess = function () {
            resolve(openreq.result);
            _advanceReadiness(dbInfo);
        };
    });
}

function _getOriginalConnection(dbInfo) {
    return _getConnection(dbInfo, false);
}

function _getUpgradedConnection(dbInfo) {
    return _getConnection(dbInfo, true);
}

function _isUpgradeNeeded(dbInfo, defaultVersion) {
    if (!dbInfo.db) {
        return true;
    }

    var isNewStore = !dbInfo.db.objectStoreNames.contains(dbInfo.storeName);
    var isDowngrade = dbInfo.version < dbInfo.db.version;
    var isUpgrade = dbInfo.version > dbInfo.db.version;

    if (isDowngrade) {
        // If the version is not the default one
        // then warn for impossible downgrade.
        if (dbInfo.version !== defaultVersion) {
            console.warn('The database "' + dbInfo.name + '"' + ' can\'t be downgraded from version ' + dbInfo.db.version + ' to version ' + dbInfo.version + '.');
        }
        // Align the versions to prevent errors.
        dbInfo.version = dbInfo.db.version;
    }

    if (isUpgrade || isNewStore) {
        // If the store is new then increment the version (if needed).
        // This will trigger an "upgradeneeded" event which is required
        // for creating a store.
        if (isNewStore) {
            var incVersion = dbInfo.db.version + 1;
            if (incVersion > dbInfo.version) {
                dbInfo.version = incVersion;
            }
        }

        return true;
    }

    return false;
}

// encode a blob for indexeddb engines that don't support blobs
function _encodeBlob(blob) {
    return new Promise$1(function (resolve, reject) {
        var reader = new FileReader();
        reader.onerror = reject;
        reader.onloadend = function (e) {
            var base64 = btoa(e.target.result || '');
            resolve({
                __local_forage_encoded_blob: true,
                data: base64,
                type: blob.type
            });
        };
        reader.readAsBinaryString(blob);
    });
}

// decode an encoded blob
function _decodeBlob(encodedBlob) {
    var arrayBuff = _binStringToArrayBuffer(atob(encodedBlob.data));
    return createBlob([arrayBuff], { type: encodedBlob.type });
}

// is this one of our fancy encoded blobs?
function _isEncodedBlob(value) {
    return value && value.__local_forage_encoded_blob;
}

// Specialize the default `ready()` function by making it dependent
// on the current database operations. Thus, the driver will be actually
// ready when it's been initialized (default) *and* there are no pending
// operations on the database (initiated by some other instances).
function _fullyReady(callback) {
    var self = this;

    var promise = self._initReady().then(function () {
        var dbContext = dbContexts[self._dbInfo.name];

        if (dbContext && dbContext.dbReady) {
            return dbContext.dbReady;
        }
    });

    executeTwoCallbacks(promise, callback, callback);
    return promise;
}

// Open the IndexedDB database (automatically creates one if one didn't
// previously exist), using any options set in the config.
function _initStorage(options) {
    var self = this;
    var dbInfo = {
        db: null
    };

    if (options) {
        for (var i in options) {
            dbInfo[i] = options[i];
        }
    }

    // Initialize a singleton container for all running localForages.
    if (!dbContexts) {
        dbContexts = {};
    }

    // Get the current context of the database;
    var dbContext = dbContexts[dbInfo.name];

    // ...or create a new context.
    if (!dbContext) {
        dbContext = {
            // Running localForages sharing a database.
            forages: [],
            // Shared database.
            db: null,
            // Database readiness (promise).
            dbReady: null,
            // Deferred operations on the database.
            deferredOperations: []
        };
        // Register the new context in the global container.
        dbContexts[dbInfo.name] = dbContext;
    }

    // Register itself as a running localForage in the current context.
    dbContext.forages.push(self);

    // Replace the default `ready()` function with the specialized one.
    if (!self._initReady) {
        self._initReady = self.ready;
        self.ready = _fullyReady;
    }

    // Create an array of initialization states of the related localForages.
    var initPromises = [];

    function ignoreErrors() {
        // Don't handle errors here,
        // just makes sure related localForages aren't pending.
        return Promise$1.resolve();
    }

    for (var j = 0; j < dbContext.forages.length; j++) {
        var forage = dbContext.forages[j];
        if (forage !== self) {
            // Don't wait for itself...
            initPromises.push(forage._initReady()["catch"](ignoreErrors));
        }
    }

    // Take a snapshot of the related localForages.
    var forages = dbContext.forages.slice(0);

    // Initialize the connection process only when
    // all the related localForages aren't pending.
    return Promise$1.all(initPromises).then(function () {
        dbInfo.db = dbContext.db;
        // Get the connection or open a new one without upgrade.
        return _getOriginalConnection(dbInfo);
    }).then(function (db) {
        dbInfo.db = db;
        if (_isUpgradeNeeded(dbInfo, self._defaultConfig.version)) {
            // Reopen the database for upgrading.
            return _getUpgradedConnection(dbInfo);
        }
        return db;
    }).then(function (db) {
        dbInfo.db = dbContext.db = db;
        self._dbInfo = dbInfo;
        // Share the final connection amongst related localForages.
        for (var k = 0; k < forages.length; k++) {
            var forage = forages[k];
            if (forage !== self) {
                // Self is already up-to-date.
                forage._dbInfo.db = dbInfo.db;
                forage._dbInfo.version = dbInfo.version;
            }
        }
    });
}

function getItem(key, callback) {
    var self = this;

    // Cast the key to a string, as that's all we can set as a key.
    if (typeof key !== 'string') {
        console.warn(key + ' used as a key, but it is not a string.');
        key = String(key);
    }

    var promise = new Promise$1(function (resolve, reject) {
        self.ready().then(function () {
            var dbInfo = self._dbInfo;
            var store = dbInfo.db.transaction(dbInfo.storeName, 'readonly').objectStore(dbInfo.storeName);
            var req = store.get(key);

            req.onsuccess = function () {
                var value = req.result;
                if (value === undefined) {
                    value = null;
                }
                if (_isEncodedBlob(value)) {
                    value = _decodeBlob(value);
                }
                resolve(value);
            };

            req.onerror = function () {
                reject(req.error);
            };
        })["catch"](reject);
    });

    executeCallback(promise, callback);
    return promise;
}

// Iterate over all items stored in database.
function iterate(iterator, callback) {
    var self = this;

    var promise = new Promise$1(function (resolve, reject) {
        self.ready().then(function () {
            var dbInfo = self._dbInfo;
            var store = dbInfo.db.transaction(dbInfo.storeName, 'readonly').objectStore(dbInfo.storeName);

            var req = store.openCursor();
            var iterationNumber = 1;

            req.onsuccess = function () {
                var cursor = req.result;

                if (cursor) {
                    var value = cursor.value;
                    if (_isEncodedBlob(value)) {
                        value = _decodeBlob(value);
                    }
                    var result = iterator(value, cursor.key, iterationNumber++);

                    if (result !== void 0) {
                        resolve(result);
                    } else {
                        cursor["continue"]();
                    }
                } else {
                    resolve();
                }
            };

            req.onerror = function () {
                reject(req.error);
            };
        })["catch"](reject);
    });

    executeCallback(promise, callback);

    return promise;
}

function setItem(key, value, callback) {
    var self = this;

    // Cast the key to a string, as that's all we can set as a key.
    if (typeof key !== 'string') {
        console.warn(key + ' used as a key, but it is not a string.');
        key = String(key);
    }

    var promise = new Promise$1(function (resolve, reject) {
        var dbInfo;
        self.ready().then(function () {
            dbInfo = self._dbInfo;
            if (toString.call(value) === '[object Blob]') {
                return _checkBlobSupport(dbInfo.db).then(function (blobSupport) {
                    if (blobSupport) {
                        return value;
                    }
                    return _encodeBlob(value);
                });
            }
            return value;
        }).then(function (value) {
            var transaction = dbInfo.db.transaction(dbInfo.storeName, 'readwrite');
            var store = transaction.objectStore(dbInfo.storeName);
            var req = store.put(value, key);

            // The reason we don't _save_ null is because IE 10 does
            // not support saving the `null` type in IndexedDB. How
            // ironic, given the bug below!
            // See: https://github.com/mozilla/localForage/issues/161
            if (value === null) {
                value = undefined;
            }

            transaction.oncomplete = function () {
                // Cast to undefined so the value passed to
                // callback/promise is the same as what one would get out
                // of `getItem()` later. This leads to some weirdness
                // (setItem('foo', undefined) will return `null`), but
                // it's not my fault localStorage is our baseline and that
                // it's weird.
                if (value === undefined) {
                    value = null;
                }

                resolve(value);
            };
            transaction.onabort = transaction.onerror = function () {
                var err = req.error ? req.error : req.transaction.error;
                reject(err);
            };
        })["catch"](reject);
    });

    executeCallback(promise, callback);
    return promise;
}

function removeItem(key, callback) {
    var self = this;

    // Cast the key to a string, as that's all we can set as a key.
    if (typeof key !== 'string') {
        console.warn(key + ' used as a key, but it is not a string.');
        key = String(key);
    }

    var promise = new Promise$1(function (resolve, reject) {
        self.ready().then(function () {
            var dbInfo = self._dbInfo;
            var transaction = dbInfo.db.transaction(dbInfo.storeName, 'readwrite');
            var store = transaction.objectStore(dbInfo.storeName);

            // We use a Grunt task to make this safe for IE and some
            // versions of Android (including those used by Cordova).
            // Normally IE won't like `.delete()` and will insist on
            // using `['delete']()`, but we have a build step that
            // fixes this for us now.
            var req = store["delete"](key);
            transaction.oncomplete = function () {
                resolve();
            };

            transaction.onerror = function () {
                reject(req.error);
            };

            // The request will be also be aborted if we've exceeded our storage
            // space.
            transaction.onabort = function () {
                var err = req.error ? req.error : req.transaction.error;
                reject(err);
            };
        })["catch"](reject);
    });

    executeCallback(promise, callback);
    return promise;
}

function clear(callback) {
    var self = this;

    var promise = new Promise$1(function (resolve, reject) {
        self.ready().then(function () {
            var dbInfo = self._dbInfo;
            var transaction = dbInfo.db.transaction(dbInfo.storeName, 'readwrite');
            var store = transaction.objectStore(dbInfo.storeName);
            var req = store.clear();

            transaction.oncomplete = function () {
                resolve();
            };

            transaction.onabort = transaction.onerror = function () {
                var err = req.error ? req.error : req.transaction.error;
                reject(err);
            };
        })["catch"](reject);
    });

    executeCallback(promise, callback);
    return promise;
}

function length(callback) {
    var self = this;

    var promise = new Promise$1(function (resolve, reject) {
        self.ready().then(function () {
            var dbInfo = self._dbInfo;
            var store = dbInfo.db.transaction(dbInfo.storeName, 'readonly').objectStore(dbInfo.storeName);
            var req = store.count();

            req.onsuccess = function () {
                resolve(req.result);
            };

            req.onerror = function () {
                reject(req.error);
            };
        })["catch"](reject);
    });

    executeCallback(promise, callback);
    return promise;
}

function key(n, callback) {
    var self = this;

    var promise = new Promise$1(function (resolve, reject) {
        if (n < 0) {
            resolve(null);

            return;
        }

        self.ready().then(function () {
            var dbInfo = self._dbInfo;
            var store = dbInfo.db.transaction(dbInfo.storeName, 'readonly').objectStore(dbInfo.storeName);

            var advanced = false;
            var req = store.openCursor();
            req.onsuccess = function () {
                var cursor = req.result;
                if (!cursor) {
                    // this means there weren't enough keys
                    resolve(null);

                    return;
                }

                if (n === 0) {
                    // We have the first key, return it if that's what they
                    // wanted.
                    resolve(cursor.key);
                } else {
                    if (!advanced) {
                        // Otherwise, ask the cursor to skip ahead n
                        // records.
                        advanced = true;
                        cursor.advance(n);
                    } else {
                        // When we get here, we've got the nth key.
                        resolve(cursor.key);
                    }
                }
            };

            req.onerror = function () {
                reject(req.error);
            };
        })["catch"](reject);
    });

    executeCallback(promise, callback);
    return promise;
}

function keys(callback) {
    var self = this;

    var promise = new Promise$1(function (resolve, reject) {
        self.ready().then(function () {
            var dbInfo = self._dbInfo;
            var store = dbInfo.db.transaction(dbInfo.storeName, 'readonly').objectStore(dbInfo.storeName);

            var req = store.openCursor();
            var keys = [];

            req.onsuccess = function () {
                var cursor = req.result;

                if (!cursor) {
                    resolve(keys);
                    return;
                }

                keys.push(cursor.key);
                cursor["continue"]();
            };

            req.onerror = function () {
                reject(req.error);
            };
        })["catch"](reject);
    });

    executeCallback(promise, callback);
    return promise;
}

var asyncStorage = {
    _driver: 'asyncStorage',
    _initStorage: _initStorage,
    iterate: iterate,
    getItem: getItem,
    setItem: setItem,
    removeItem: removeItem,
    clear: clear,
    length: length,
    key: key,
    keys: keys
};

// Sadly, the best way to save binary data in WebSQL/localStorage is serializing
// it to Base64, so this is how we store it to prevent very strange errors with less
// verbose ways of binary <-> string data storage.
var BASE_CHARS = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';

var BLOB_TYPE_PREFIX = '~~local_forage_type~';
var BLOB_TYPE_PREFIX_REGEX = /^~~local_forage_type~([^~]+)~/;

var SERIALIZED_MARKER = '__lfsc__:';
var SERIALIZED_MARKER_LENGTH = SERIALIZED_MARKER.length;

// OMG the serializations!
var TYPE_ARRAYBUFFER = 'arbf';
var TYPE_BLOB = 'blob';
var TYPE_INT8ARRAY = 'si08';
var TYPE_UINT8ARRAY = 'ui08';
var TYPE_UINT8CLAMPEDARRAY = 'uic8';
var TYPE_INT16ARRAY = 'si16';
var TYPE_INT32ARRAY = 'si32';
var TYPE_UINT16ARRAY = 'ur16';
var TYPE_UINT32ARRAY = 'ui32';
var TYPE_FLOAT32ARRAY = 'fl32';
var TYPE_FLOAT64ARRAY = 'fl64';
var TYPE_SERIALIZED_MARKER_LENGTH = SERIALIZED_MARKER_LENGTH + TYPE_ARRAYBUFFER.length;

var toString$1 = Object.prototype.toString;

function stringToBuffer(serializedString) {
    // Fill the string into a ArrayBuffer.
    var bufferLength = serializedString.length * 0.75;
    var len = serializedString.length;
    var i;
    var p = 0;
    var encoded1, encoded2, encoded3, encoded4;

    if (serializedString[serializedString.length - 1] === '=') {
        bufferLength--;
        if (serializedString[serializedString.length - 2] === '=') {
            bufferLength--;
        }
    }

    var buffer = new ArrayBuffer(bufferLength);
    var bytes = new Uint8Array(buffer);

    for (i = 0; i < len; i += 4) {
        encoded1 = BASE_CHARS.indexOf(serializedString[i]);
        encoded2 = BASE_CHARS.indexOf(serializedString[i + 1]);
        encoded3 = BASE_CHARS.indexOf(serializedString[i + 2]);
        encoded4 = BASE_CHARS.indexOf(serializedString[i + 3]);

        /*jslint bitwise: true */
        bytes[p++] = encoded1 << 2 | encoded2 >> 4;
        bytes[p++] = (encoded2 & 15) << 4 | encoded3 >> 2;
        bytes[p++] = (encoded3 & 3) << 6 | encoded4 & 63;
    }
    return buffer;
}

// Converts a buffer to a string to store, serialized, in the backend
// storage library.
function bufferToString(buffer) {
    // base64-arraybuffer
    var bytes = new Uint8Array(buffer);
    var base64String = '';
    var i;

    for (i = 0; i < bytes.length; i += 3) {
        /*jslint bitwise: true */
        base64String += BASE_CHARS[bytes[i] >> 2];
        base64String += BASE_CHARS[(bytes[i] & 3) << 4 | bytes[i + 1] >> 4];
        base64String += BASE_CHARS[(bytes[i + 1] & 15) << 2 | bytes[i + 2] >> 6];
        base64String += BASE_CHARS[bytes[i + 2] & 63];
    }

    if (bytes.length % 3 === 2) {
        base64String = base64String.substring(0, base64String.length - 1) + '=';
    } else if (bytes.length % 3 === 1) {
        base64String = base64String.substring(0, base64String.length - 2) + '==';
    }

    return base64String;
}

// Serialize a value, afterwards executing a callback (which usually
// instructs the `setItem()` callback/promise to be executed). This is how
// we store binary data with localStorage.
function serialize(value, callback) {
    var valueType = '';
    if (value) {
        valueType = toString$1.call(value);
    }

    // Cannot use `value instanceof ArrayBuffer` or such here, as these
    // checks fail when running the tests using casper.js...
    //
    // TODO: See why those tests fail and use a better solution.
    if (value && (valueType === '[object ArrayBuffer]' || value.buffer && toString$1.call(value.buffer) === '[object ArrayBuffer]')) {
        // Convert binary arrays to a string and prefix the string with
        // a special marker.
        var buffer;
        var marker = SERIALIZED_MARKER;

        if (value instanceof ArrayBuffer) {
            buffer = value;
            marker += TYPE_ARRAYBUFFER;
        } else {
            buffer = value.buffer;

            if (valueType === '[object Int8Array]') {
                marker += TYPE_INT8ARRAY;
            } else if (valueType === '[object Uint8Array]') {
                marker += TYPE_UINT8ARRAY;
            } else if (valueType === '[object Uint8ClampedArray]') {
                marker += TYPE_UINT8CLAMPEDARRAY;
            } else if (valueType === '[object Int16Array]') {
                marker += TYPE_INT16ARRAY;
            } else if (valueType === '[object Uint16Array]') {
                marker += TYPE_UINT16ARRAY;
            } else if (valueType === '[object Int32Array]') {
                marker += TYPE_INT32ARRAY;
            } else if (valueType === '[object Uint32Array]') {
                marker += TYPE_UINT32ARRAY;
            } else if (valueType === '[object Float32Array]') {
                marker += TYPE_FLOAT32ARRAY;
            } else if (valueType === '[object Float64Array]') {
                marker += TYPE_FLOAT64ARRAY;
            } else {
                callback(new Error('Failed to get type for BinaryArray'));
            }
        }

        callback(marker + bufferToString(buffer));
    } else if (valueType === '[object Blob]') {
        // Conver the blob to a binaryArray and then to a string.
        var fileReader = new FileReader();

        fileReader.onload = function () {
            // Backwards-compatible prefix for the blob type.
            var str = BLOB_TYPE_PREFIX + value.type + '~' + bufferToString(this.result);

            callback(SERIALIZED_MARKER + TYPE_BLOB + str);
        };

        fileReader.readAsArrayBuffer(value);
    } else {
        try {
            callback(JSON.stringify(value));
        } catch (e) {
            console.error("Couldn't convert value into a JSON string: ", value);

            callback(null, e);
        }
    }
}

// Deserialize data we've inserted into a value column/field. We place
// special markers into our strings to mark them as encoded; this isn't
// as nice as a meta field, but it's the only sane thing we can do whilst
// keeping localStorage support intact.
//
// Oftentimes this will just deserialize JSON content, but if we have a
// special marker (SERIALIZED_MARKER, defined above), we will extract
// some kind of arraybuffer/binary data/typed array out of the string.
function deserialize(value) {
    // If we haven't marked this string as being specially serialized (i.e.
    // something other than serialized JSON), we can just return it and be
    // done with it.
    if (value.substring(0, SERIALIZED_MARKER_LENGTH) !== SERIALIZED_MARKER) {
        return JSON.parse(value);
    }

    // The following code deals with deserializing some kind of Blob or
    // TypedArray. First we separate out the type of data we're dealing
    // with from the data itself.
    var serializedString = value.substring(TYPE_SERIALIZED_MARKER_LENGTH);
    var type = value.substring(SERIALIZED_MARKER_LENGTH, TYPE_SERIALIZED_MARKER_LENGTH);

    var blobType;
    // Backwards-compatible blob type serialization strategy.
    // DBs created with older versions of localForage will simply not have the blob type.
    if (type === TYPE_BLOB && BLOB_TYPE_PREFIX_REGEX.test(serializedString)) {
        var matcher = serializedString.match(BLOB_TYPE_PREFIX_REGEX);
        blobType = matcher[1];
        serializedString = serializedString.substring(matcher[0].length);
    }
    var buffer = stringToBuffer(serializedString);

    // Return the right type based on the code/type set during
    // serialization.
    switch (type) {
        case TYPE_ARRAYBUFFER:
            return buffer;
        case TYPE_BLOB:
            return createBlob([buffer], { type: blobType });
        case TYPE_INT8ARRAY:
            return new Int8Array(buffer);
        case TYPE_UINT8ARRAY:
            return new Uint8Array(buffer);
        case TYPE_UINT8CLAMPEDARRAY:
            return new Uint8ClampedArray(buffer);
        case TYPE_INT16ARRAY:
            return new Int16Array(buffer);
        case TYPE_UINT16ARRAY:
            return new Uint16Array(buffer);
        case TYPE_INT32ARRAY:
            return new Int32Array(buffer);
        case TYPE_UINT32ARRAY:
            return new Uint32Array(buffer);
        case TYPE_FLOAT32ARRAY:
            return new Float32Array(buffer);
        case TYPE_FLOAT64ARRAY:
            return new Float64Array(buffer);
        default:
            throw new Error('Unkown type: ' + type);
    }
}

var localforageSerializer = {
    serialize: serialize,
    deserialize: deserialize,
    stringToBuffer: stringToBuffer,
    bufferToString: bufferToString
};

/*
 * Includes code from:
 *
 * base64-arraybuffer
 * https://github.com/niklasvh/base64-arraybuffer
 *
 * Copyright (c) 2012 Niklas von Hertzen
 * Licensed under the MIT license.
 */
// Open the WebSQL database (automatically creates one if one didn't
// previously exist), using any options set in the config.
function _initStorage$1(options) {
    var self = this;
    var dbInfo = {
        db: null
    };

    if (options) {
        for (var i in options) {
            dbInfo[i] = typeof options[i] !== 'string' ? options[i].toString() : options[i];
        }
    }

    var dbInfoPromise = new Promise$1(function (resolve, reject) {
        // Open the database; the openDatabase API will automatically
        // create it for us if it doesn't exist.
        try {
            dbInfo.db = openDatabase(dbInfo.name, String(dbInfo.version), dbInfo.description, dbInfo.size);
        } catch (e) {
            return reject(e);
        }

        // Create our key/value table if it doesn't exist.
        dbInfo.db.transaction(function (t) {
            t.executeSql('CREATE TABLE IF NOT EXISTS ' + dbInfo.storeName + ' (id INTEGER PRIMARY KEY, key unique, value)', [], function () {
                self._dbInfo = dbInfo;
                resolve();
            }, function (t, error) {
                reject(error);
            });
        });
    });

    dbInfo.serializer = localforageSerializer;
    return dbInfoPromise;
}

function getItem$1(key, callback) {
    var self = this;

    // Cast the key to a string, as that's all we can set as a key.
    if (typeof key !== 'string') {
        console.warn(key + ' used as a key, but it is not a string.');
        key = String(key);
    }

    var promise = new Promise$1(function (resolve, reject) {
        self.ready().then(function () {
            var dbInfo = self._dbInfo;
            dbInfo.db.transaction(function (t) {
                t.executeSql('SELECT * FROM ' + dbInfo.storeName + ' WHERE key = ? LIMIT 1', [key], function (t, results) {
                    var result = results.rows.length ? results.rows.item(0).value : null;

                    // Check to see if this is serialized content we need to
                    // unpack.
                    if (result) {
                        result = dbInfo.serializer.deserialize(result);
                    }

                    resolve(result);
                }, function (t, error) {

                    reject(error);
                });
            });
        })["catch"](reject);
    });

    executeCallback(promise, callback);
    return promise;
}

function iterate$1(iterator, callback) {
    var self = this;

    var promise = new Promise$1(function (resolve, reject) {
        self.ready().then(function () {
            var dbInfo = self._dbInfo;

            dbInfo.db.transaction(function (t) {
                t.executeSql('SELECT * FROM ' + dbInfo.storeName, [], function (t, results) {
                    var rows = results.rows;
                    var length = rows.length;

                    for (var i = 0; i < length; i++) {
                        var item = rows.item(i);
                        var result = item.value;

                        // Check to see if this is serialized content
                        // we need to unpack.
                        if (result) {
                            result = dbInfo.serializer.deserialize(result);
                        }

                        result = iterator(result, item.key, i + 1);

                        // void(0) prevents problems with redefinition
                        // of `undefined`.
                        if (result !== void 0) {
                            resolve(result);
                            return;
                        }
                    }

                    resolve();
                }, function (t, error) {
                    reject(error);
                });
            });
        })["catch"](reject);
    });

    executeCallback(promise, callback);
    return promise;
}

function _setItem(key, value, callback, retriesLeft) {
    var self = this;

    // Cast the key to a string, as that's all we can set as a key.
    if (typeof key !== 'string') {
        console.warn(key + ' used as a key, but it is not a string.');
        key = String(key);
    }

    var promise = new Promise$1(function (resolve, reject) {
        self.ready().then(function () {
            // The localStorage API doesn't return undefined values in an
            // "expected" way, so undefined is always cast to null in all
            // drivers. See: https://github.com/mozilla/localForage/pull/42
            if (value === undefined) {
                value = null;
            }

            // Save the original value to pass to the callback.
            var originalValue = value;

            var dbInfo = self._dbInfo;
            dbInfo.serializer.serialize(value, function (value, error) {
                if (error) {
                    reject(error);
                } else {
                    dbInfo.db.transaction(function (t) {
                        t.executeSql('INSERT OR REPLACE INTO ' + dbInfo.storeName + ' (key, value) VALUES (?, ?)', [key, value], function () {
                            resolve(originalValue);
                        }, function (t, error) {
                            reject(error);
                        });
                    }, function (sqlError) {
                        // The transaction failed; check
                        // to see if it's a quota error.
                        if (sqlError.code === sqlError.QUOTA_ERR) {
                            // We reject the callback outright for now, but
                            // it's worth trying to re-run the transaction.
                            // Even if the user accepts the prompt to use
                            // more storage on Safari, this error will
                            // be called.
                            //
                            // Try to re-run the transaction.
                            if (retriesLeft > 0) {
                                resolve(_setItem.apply(self, [key, originalValue, callback, retriesLeft - 1]));
                                return;