i18nextLocalStorageCache.js

(function (global, factory) {
	typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() :
	typeof define === 'function' && define.amd ? define(factory) :
	(global.i18nextLocalStorageCache = factory());
}(this, (function () { 'use strict';

var arr = [];
var each = arr.forEach;
var slice = arr.slice;

function defaults(obj) {
  each.call(slice.call(arguments, 1), function (source) {
    if (source) {
      for (var prop in source) {
        if (obj[prop] === undefined) obj[prop] = source[prop];
      }
    }
  });
  return obj;
}



function debounce(func, wait, immediate) {
  var timeout;
  return function () {
    var context = this,
        args = arguments;
    var later = function later() {
      timeout = null;
      if (!immediate) func.apply(context, args);
    };
    var callNow = immediate && !timeout;
    clearTimeout(timeout);
    timeout = setTimeout(later, wait);
    if (callNow) func.apply(context, args);
  };
}

var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();

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

var storage = {
  setItem: function setItem(key, value) {
    if (window.localStorage) {
      try {
        window.localStorage.setItem(key, value);
      } catch (e) {
        // f.log('failed to set value for key "' + key + '" to localStorage.');
      }
    }
  },
  getItem: function getItem(key, value) {
    if (window.localStorage) {
      try {
        return window.localStorage.getItem(key, value);
      } catch (e) {
        // f.log('failed to get value for key "' + key + '" from localStorage.');
      }
    }
    return undefined;
  }
};

function getDefaults() {
  return {
    enabled: false,
    prefix: 'i18next_res_',
    expirationTime: 7 * 24 * 60 * 60 * 1000,
    versions: {}
  };
}

var Cache = function () {
  function Cache(services) {
    var options = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {};

    _classCallCheck(this, Cache);

    this.init(services, options);

    this.type = 'cache';
    this.debouncedStore = debounce(this.store, 10000);
  }

  _createClass(Cache, [{
    key: 'init',
    value: function init(services) {
      var options = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {};

      this.services = services;
      this.options = defaults(options, this.options || {}, getDefaults());
    }
  }, {
    key: 'load',
    value: function load(lngs, callback) {
      var _this = this;

      var store = {};
      var nowMS = new Date().getTime();

      if (!window.localStorage || !lngs.length) {
        return callback(null, null);
      }

      var todo = lngs.length;

      lngs.forEach(function (lng) {
        var local = storage.getItem(_this.options.prefix + lng);

        if (local) {
          local = JSON.parse(local);
          if (
          // expiration field is mandatory, and should not be expired
          local.i18nStamp && local.i18nStamp + _this.options.expirationTime > nowMS &&

          // there should be no language version set, or if it is, it should match the one in translation
          _this.options.versions[lng] === local.i18nVersion) {
            delete local.i18nVersion;
            store[lng] = local;
          }
        }

        todo -= 1;
        if (todo === 0) {
          callback(null, store);
        }
      });
      return undefined;
    }
  }, {
    key: 'store',
    value: function store(storeParam) {
      var store = storeParam;
      if (window.localStorage) {
        for (var m in store) {
          // eslint-disable-line
          // timestamp
          store[m].i18nStamp = new Date().getTime();

          // language version (if set)
          if (this.options.versions[m]) {
            store[m].i18nVersion = this.options.versions[m];
          }

          // save
          storage.setItem(this.options.prefix + m, JSON.stringify(store[m]));
        }
      }
    }
  }, {
    key: 'save',
    value: function save(store) {
      this.debouncedStore(store);
    }
  }]);

  return Cache;
}();

Cache.type = 'cache';

return Cache;

})));