kinto-offline-client.js

/*
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
"use strict";

/*
 * This file is generated from kinto.js - do not modify directly.
 */

// This is required because with Babel compiles ES2015 modules into a
// require() form that tries to keep its modules on "this", but
// doesn't specify "this", leaving it to default to the global
// object. However, in strict mode, "this" no longer defaults to the
// global object, so expose the global object explicitly. Babel's
// compiled output will use a variable called "global" if one is
// present.
//
// See https://bugzilla.mozilla.org/show_bug.cgi?id=1394556#c3 for
// more details.
const global = this;

var EXPORTED_SYMBOLS = ["Kinto"];

/*
 * Version 12.6.0 - f14a3e6
 */

(function(f){if(typeof exports==="object"&&typeof module!=="undefined"){module.exports=f()}else if(typeof define==="function"&&define.amd){define([],f)}else{var g;if(typeof window!=="undefined"){g=window}else if(typeof global!=="undefined"){g=global}else if(typeof self!=="undefined"){g=self}else{g=this}g.Kinto = f()}})(function(){var define,module,exports;return (function(){function r(e,n,t){function o(i,f){if(!n[i]){if(!e[i]){var c="function"==typeof require&&require;if(!f&&c)return c(i,!0);if(u)return u(i,!0);var a=new Error("Cannot find module '"+i+"'");throw a.code="MODULE_NOT_FOUND",a}var p=n[i]={exports:{}};e[i][0].call(p.exports,function(r){var n=e[i][1][r];return o(n||r)},p,p.exports,r,e,n,t)}return n[i].exports}for(var u="function"==typeof require&&require,i=0;i<t.length;i++)o(t[i]);return o}return r})()({1:[function(require,module,exports){
/*
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;

var _KintoBase = _interopRequireDefault(require("../src/KintoBase"));

var _base = _interopRequireDefault(require("../src/adapters/base"));

var _IDB = _interopRequireDefault(require("../src/adapters/IDB"));

var _utils = require("../src/utils");

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

ChromeUtils.import("resource://gre/modules/Timer.jsm", global);
const {
  XPCOMUtils
} = ChromeUtils.import("resource://gre/modules/XPCOMUtils.jsm");
XPCOMUtils.defineLazyGlobalGetters(global, ["fetch", "indexedDB"]);
ChromeUtils.defineModuleGetter(global, "EventEmitter", "resource://gre/modules/EventEmitter.jsm"); // Use standalone kinto-http module landed in FFx.

ChromeUtils.defineModuleGetter(global, "KintoHttpClient", "resource://services-common/kinto-http-client.js");
XPCOMUtils.defineLazyGetter(global, "generateUUID", () => {
  const {
    generateUUID
  } = Cc["@mozilla.org/uuid-generator;1"].getService(Ci.nsIUUIDGenerator);
  return generateUUID;
});

class Kinto extends _KintoBase.default {
  static get adapters() {
    return {
      BaseAdapter: _base.default,
      IDB: _IDB.default
    };
  }

  constructor(options = {}) {
    const events = {};
    EventEmitter.decorate(events);
    const defaults = {
      adapter: _IDB.default,
      events,
      ApiClass: KintoHttpClient
    };
    super({ ...defaults,
      ...options
    });
  }

  collection(collName, options = {}) {
    const idSchema = {
      validate(id) {
        return typeof id == "string" && _utils.RE_RECORD_ID.test(id);
      },

      generate() {
        return generateUUID().toString().replace(/[{}]/g, "");
      }

    };
    return super.collection(collName, {
      idSchema,
      ...options
    });
  }

} // This fixes compatibility with CommonJS required by browserify.
// See http://stackoverflow.com/questions/33505992/babel-6-changes-how-it-exports-default/33683495#33683495


exports.default = Kinto;

if (typeof module === "object") {
  module.exports = Kinto;
}

},{"../src/KintoBase":3,"../src/adapters/IDB":4,"../src/adapters/base":5,"../src/utils":7}],2:[function(require,module,exports){

},{}],3:[function(require,module,exports){
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;

var _collection = _interopRequireDefault(require("./collection"));

var _base = _interopRequireDefault(require("./adapters/base"));

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

const DEFAULT_BUCKET_NAME = "default";
const DEFAULT_REMOTE = "http://localhost:8888/v1";
const DEFAULT_RETRY = 1;
/**
 * KintoBase class.
 */

class KintoBase {
  /**
   * Provides a public access to the base adapter class. Users can create a
   * custom DB adapter by extending {@link BaseAdapter}.
   *
   * @type {Object}
   */
  static get adapters() {
    return {
      BaseAdapter: _base.default
    };
  }
  /**
   * Synchronization strategies. Available strategies are:
   *
   * - `MANUAL`: Conflicts will be reported in a dedicated array.
   * - `SERVER_WINS`: Conflicts are resolved using remote data.
   * - `CLIENT_WINS`: Conflicts are resolved using local data.
   *
   * @type {Object}
   */


  static get syncStrategy() {
    return _collection.default.strategy;
  }
  /**
   * Constructor.
   *
   * Options:
   * - `{String}`       `remote`         The server URL to use.
   * - `{String}`       `bucket`         The collection bucket name.
   * - `{EventEmitter}` `events`         Events handler.
   * - `{BaseAdapter}`  `adapter`        The base DB adapter class.
   * - `{Object}`       `adapterOptions` Options given to the adapter.
   * - `{Object}`       `headers`        The HTTP headers to use.
   * - `{Object}`       `retry`          Number of retries when the server fails to process the request (default: `1`)
   * - `{String}`       `requestMode`    The HTTP CORS mode to use.
   * - `{Number}`       `timeout`        The requests timeout in ms (default: `5000`).
   *
   * @param  {Object} options The options object.
   */


  constructor(options = {}) {
    const defaults = {
      bucket: DEFAULT_BUCKET_NAME,
      remote: DEFAULT_REMOTE,
      retry: DEFAULT_RETRY
    };
    this._options = { ...defaults,
      ...options
    };

    if (!this._options.adapter) {
      throw new Error("No adapter provided");
    }

    const {
      ApiClass,
      events,
      headers,
      remote,
      requestMode,
      retry,
      timeout
    } = this._options; // public properties

    /**
     * The kinto HTTP client instance.
     * @type {KintoClient}
     */

    this.api = new ApiClass(remote, {
      events,
      headers,
      requestMode,
      retry,
      timeout
    });
    /**
     * The event emitter instance.
     * @type {EventEmitter}
     */

    this.events = this._options.events;
  }
  /**
   * Creates a {@link Collection} instance. The second (optional) parameter
   * will set collection-level options like e.g. `remoteTransformers`.
   *
   * @param  {String} collName The collection name.
   * @param  {Object} [options={}]                 Extra options or override client's options.
   * @param  {Object} [options.idSchema]           IdSchema instance (default: UUID)
   * @param  {Object} [options.remoteTransformers] Array<RemoteTransformer> (default: `[]`])
   * @param  {Object} [options.hooks]              Array<Hook> (default: `[]`])
   * @param  {Object} [options.localFields]        Array<Field> (default: `[]`])
   * @return {Collection}
   */


  collection(collName, options = {}) {
    if (!collName) {
      throw new Error("missing collection name");
    }

    const {
      bucket,
      events,
      adapter,
      adapterOptions
    } = { ...this._options,
      ...options
    };
    const {
      idSchema,
      remoteTransformers,
      hooks,
      localFields
    } = options;
    return new _collection.default(bucket, collName, this.api, {
      events,
      adapter,
      adapterOptions,
      idSchema,
      remoteTransformers,
      hooks,
      localFields
    });
  }

}

exports.default = KintoBase;

},{"./adapters/base":5,"./collection":6}],4:[function(require,module,exports){
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.open = open;
exports.execute = execute;
exports.default = void 0;

var _base = _interopRequireDefault(require("./base.js"));

var _utils = require("../utils");

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

const INDEXED_FIELDS = ["id", "_status", "last_modified"];
/**
 * Small helper that wraps the opening of an IndexedDB into a Promise.
 *
 * @param dbname          {String}   The database name.
 * @param version         {Integer}  Schema version
 * @param onupgradeneeded {Function} The callback to execute if schema is
 *                                   missing or different.
 * @return {Promise<IDBDatabase>}
 */

async function open(dbname, {
  version,
  onupgradeneeded
}) {
  return new Promise((resolve, reject) => {
    const request = indexedDB.open(dbname, version);

    request.onupgradeneeded = event => {
      const db = event.target.result;

      db.onerror = event => reject(event.target.error);

      return onupgradeneeded(event);
    };

    request.onerror = event => {
      reject(event.target.error);
    };

    request.onsuccess = event => {
      const db = event.target.result;
      resolve(db);
    };
  });
}
/**
 * Helper to run the specified callback in a single transaction on the
 * specified store.
 * The helper focuses on transaction wrapping into a promise.
 *
 * @param db           {IDBDatabase} The database instance.
 * @param name         {String}      The store name.
 * @param callback     {Function}    The piece of code to execute in the transaction.
 * @param options      {Object}      Options.
 * @param options.mode {String}      Transaction mode (default: read).
 * @return {Promise} any value returned by the callback.
 */


async function execute(db, name, callback, options = {}) {
  const {
    mode
  } = options;
  return new Promise((resolve, reject) => {
    // On Safari, calling IDBDatabase.transaction with mode == undefined raises
    // a TypeError.
    const transaction = mode ? db.transaction([name], mode) : db.transaction([name]);
    const store = transaction.objectStore(name); // Let the callback abort this transaction.

    const abort = e => {
      transaction.abort();
      reject(e);
    }; // Execute the specified callback **synchronously**.


    let result;

    try {
      result = callback(store, abort);
    } catch (e) {
      abort(e);
    }

    transaction.onerror = event => reject(event.target.error);

    transaction.oncomplete = event => resolve(result);
  });
}
/**
 * Helper to wrap the deletion of an IndexedDB database into a promise.
 *
 * @param dbName {String} the database to delete
 * @return {Promise}
 */


async function deleteDatabase(dbName) {
  return new Promise((resolve, reject) => {
    const request = indexedDB.deleteDatabase(dbName);

    request.onsuccess = event => resolve(event.target);

    request.onerror = event => reject(event.target.error);
  });
}
/**
 * IDB cursor handlers.
 * @type {Object}
 */


const cursorHandlers = {
  all(filters, done) {
    const results = [];
    return event => {
      const cursor = event.target.result;

      if (cursor) {
        const {
          value
        } = cursor;

        if ((0, _utils.filterObject)(filters, value)) {
          results.push(value);
        }

        cursor.continue();
      } else {
        done(results);
      }
    };
  },

  in(values, filters, done) {
    const results = [];
    let i = 0;
    return function (event) {
      const cursor = event.target.result;

      if (!cursor) {
        done(results);
        return;
      }

      const {
        key,
        value
      } = cursor; // `key` can be an array of two values (see `keyPath` in indices definitions).
      // `values` can be an array of arrays if we filter using an index whose key path
      // is an array (eg. `cursorHandlers.in([["bid/cid", 42], ["bid/cid", 43]], ...)`)

      while (key > values[i]) {
        // The cursor has passed beyond this key. Check next.
        ++i;

        if (i === values.length) {
          done(results); // There is no next. Stop searching.

          return;
        }
      }

      const isEqual = Array.isArray(key) ? (0, _utils.arrayEqual)(key, values[i]) : key === values[i];

      if (isEqual) {
        if ((0, _utils.filterObject)(filters, value)) {
          results.push(value);
        }

        cursor.continue();
      } else {
        cursor.continue(values[i]);
      }
    };
  }

};
/**
 * Creates an IDB request and attach it the appropriate cursor event handler to
 * perform a list query.
 *
 * Multiple matching values are handled by passing an array.
 *
 * @param  {String}           cid        The collection id (ie. `{bid}/{cid}`)
 * @param  {IDBStore}         store      The IDB store.
 * @param  {Object}           filters    Filter the records by field.
 * @param  {Function}         done       The operation completion handler.
 * @return {IDBRequest}
 */

function createListRequest(cid, store, filters, done) {
  const filterFields = Object.keys(filters); // If no filters, get all results in one bulk.

  if (filterFields.length == 0) {
    const request = store.index("cid").getAll(IDBKeyRange.only(cid));

    request.onsuccess = event => done(event.target.result);

    return request;
  } // Introspect filters and check if they leverage an indexed field.


  const indexField = filterFields.find(field => {
    return INDEXED_FIELDS.includes(field);
  });

  if (!indexField) {
    // Iterate on all records for this collection (ie. cid)
    const isSubQuery = Object.keys(filters).some(key => key.includes(".")); // (ie. filters: {"article.title": "hello"})

    if (isSubQuery) {
      const newFilter = (0, _utils.transformSubObjectFilters)(filters);
      const request = store.index("cid").openCursor(IDBKeyRange.only(cid));
      request.onsuccess = cursorHandlers.all(newFilter, done);
      return request;
    }

    const request = store.index("cid").openCursor(IDBKeyRange.only(cid));
    request.onsuccess = cursorHandlers.all(filters, done);
    return request;
  } // If `indexField` was used already, don't filter again.


  const remainingFilters = (0, _utils.omitKeys)(filters, [indexField]); // value specified in the filter (eg. `filters: { _status: ["created", "updated"] }`)

  const value = filters[indexField]; // For the "id" field, use the primary key.

  const indexStore = indexField == "id" ? store : store.index(indexField); // WHERE IN equivalent clause

  if (Array.isArray(value)) {
    if (value.length === 0) {
      return done([]);
    }

    const values = value.map(i => [cid, i]).sort();
    const range = IDBKeyRange.bound(values[0], values[values.length - 1]);
    const request = indexStore.openCursor(range);
    request.onsuccess = cursorHandlers.in(values, remainingFilters, done);
    return request;
  } // If no filters on custom attribute, get all results in one bulk.


  if (remainingFilters.length == 0) {
    const request = indexStore.getAll(IDBKeyRange.only([cid, value]));

    request.onsuccess = event => done(event.target.result);

    return request;
  } // WHERE field = value clause


  const request = indexStore.openCursor(IDBKeyRange.only([cid, value]));
  request.onsuccess = cursorHandlers.all(remainingFilters, done);
  return request;
}
/**
 * IndexedDB adapter.
 *
 * This adapter doesn't support any options.
 */


class IDB extends _base.default {
  /**
   * Constructor.
   *
   * @param  {String} cid  The key base for this collection (eg. `bid/cid`)
   * @param  {Object} options
   * @param  {String} options.dbName         The IndexedDB name (default: `"KintoDB"`)
   * @param  {String} options.migrateOldData Whether old database data should be migrated (default: `false`)
   */
  constructor(cid, options = {}) {
    super();
    this.cid = cid;
    this.dbName = options.dbName || "KintoDB";
    this._options = options;
    this._db = null;
  }

  _handleError(method, err) {
    const error = new Error(`IndexedDB ${method}() ${err.message}`);
    error.stack = err.stack;
    throw error;
  }
  /**
   * Ensures a connection to the IndexedDB database has been opened.
   *
   * @override
   * @return {Promise}
   */


  async open() {
    if (this._db) {
      return this;
    } // In previous versions, we used to have a database with name `${bid}/${cid}`.
    // Check if it exists, and migrate data once new schema is in place.
    // Note: the built-in migrations from IndexedDB can only be used if the
    // database name does not change.


    const dataToMigrate = this._options.migrateOldData ? await migrationRequired(this.cid) : null;
    this._db = await open(this.dbName, {
      version: 2,
      onupgradeneeded: event => {
        const db = event.target.result;

        if (event.oldVersion < 1) {
          // Records store
          const recordsStore = db.createObjectStore("records", {
            keyPath: ["_cid", "id"]
          }); // An index to obtain all the records in a collection.

          recordsStore.createIndex("cid", "_cid"); // Here we create indices for every known field in records by collection.
          // Local record status ("synced", "created", "updated", "deleted")

          recordsStore.createIndex("_status", ["_cid", "_status"]); // Last modified field

          recordsStore.createIndex("last_modified", ["_cid", "last_modified"]); // Timestamps store

          db.createObjectStore("timestamps", {
            keyPath: "cid"
          });
        }

        if (event.oldVersion < 2) {
          // Collections store
          db.createObjectStore("collections", {
            keyPath: "cid"
          });
        }
      }
    });

    if (dataToMigrate) {
      const {
        records,
        timestamp
      } = dataToMigrate;
      await this.importBulk(records);
      await this.saveLastModified(timestamp);
      console.log(`${this.cid}: data was migrated successfully.`); // Delete the old database.

      await deleteDatabase(this.cid);
      console.warn(`${this.cid}: old database was deleted.`);
    }

    return this;
  }
  /**
   * Closes current connection to the database.
   *
   * @override
   * @return {Promise}
   */


  close() {
    if (this._db) {
      this._db.close(); // indexedDB.close is synchronous


      this._db = null;
    }

    return Promise.resolve();
  }
  /**
   * Returns a transaction and an object store for a store name.
   *
   * To determine if a transaction has completed successfully, we should rather
   * listen to the transaction’s complete event rather than the IDBObjectStore
   * request’s success event, because the transaction may still fail after the
   * success event fires.
   *
   * @param  {String}      name  Store name
   * @param  {Function}    callback to execute
   * @param  {Object}      options Options
   * @param  {String}      options.mode  Transaction mode ("readwrite" or undefined)
   * @return {Object}
   */


  async prepare(name, callback, options) {
    await this.open();
    await execute(this._db, name, callback, options);
  }
  /**
   * Deletes every records in the current collection.
   *
   * @override
   * @return {Promise}
   */


  async clear() {
    try {
      await this.prepare("records", store => {
        const range = IDBKeyRange.only(this.cid);
        const request = store.index("cid").openKeyCursor(range);

        request.onsuccess = event => {
          const cursor = event.target.result;

          if (cursor) {
            store.delete(cursor.primaryKey);
            cursor.continue();
          }
        };

        return request;
      }, {
        mode: "readwrite"
      });
    } catch (e) {
      this._handleError("clear", e);
    }
  }
  /**
   * Executes the set of synchronous CRUD operations described in the provided
   * callback within an IndexedDB transaction, for current db store.
   *
   * The callback will be provided an object exposing the following synchronous
   * CRUD operation methods: get, create, update, delete.
   *
   * Important note: because limitations in IndexedDB implementations, no
   * asynchronous code should be performed within the provided callback; the
   * promise will therefore be rejected if the callback returns a Promise.
   *
   * Options:
   * - {Array} preload: The list of record IDs to fetch and make available to
   *   the transaction object get() method (default: [])
   *
   * @example
   * const db = new IDB("example");
   * const result = await db.execute(transaction => {
   *   transaction.create({id: 1, title: "foo"});
   *   transaction.update({id: 2, title: "bar"});
   *   transaction.delete(3);
   *   return "foo";
   * });
   *
   * @override
   * @param  {Function} callback The operation description callback.
   * @param  {Object}   options  The options object.
   * @return {Promise}
   */


  async execute(callback, options = {
    preload: []
  }) {
    // Transactions in IndexedDB are autocommited when a callback does not
    // perform any additional operation.
    // The way Promises are implemented in Firefox (see https://bugzilla.mozilla.org/show_bug.cgi?id=1193394)
    // prevents using within an opened transaction.
    // To avoid managing asynchronocity in the specified `callback`, we preload
    // a list of record in order to execute the `callback` synchronously.
    // See also:
    // - http://stackoverflow.com/a/28388805/330911
    // - http://stackoverflow.com/a/10405196
    // - https://jakearchibald.com/2015/tasks-microtasks-queues-and-schedules/
    let result;
    await this.prepare("records", (store, abort) => {
      const runCallback = (preloaded = []) => {
        // Expose a consistent API for every adapter instead of raw store methods.
        const proxy = transactionProxy(this, store, preloaded); // The callback is executed synchronously within the same transaction.

        try {
          const returned = callback(proxy);

          if (returned instanceof Promise) {
            // XXX: investigate how to provide documentation details in error.
            throw new Error("execute() callback should not return a Promise.");
          } // Bring to scope that will be returned (once promise awaited).


          result = returned;
        } catch (e) {
          // The callback has thrown an error explicitly. Abort transaction cleanly.
          abort(e);
        }
      }; // No option to preload records, go straight to `callback`.


      if (!options.preload.length) {
        return runCallback();
      } // Preload specified records using a list request.


      const filters = {
        id: options.preload
      };
      createListRequest(this.cid, store, filters, records => {
        // Store obtained records by id.
        const preloaded = {};

        for (const record of records) {
          delete record["_cid"];
          preloaded[record.id] = record;
        }

        runCallback(preloaded);
      });
    }, {
      mode: "readwrite"
    });
    return result;
  }
  /**
   * Retrieve a record by its primary key from the IndexedDB database.
   *
   * @override
   * @param  {String} id The record id.
   * @return {Promise}
   */


  async get(id) {
    try {
      let record;
      await this.prepare("records", store => {
        store.get([this.cid, id]).onsuccess = e => record = e.target.result;
      });
      return record;
    } catch (e) {
      this._handleError("get", e);
    }
  }
  /**
   * Lists all records from the IndexedDB database.
   *
   * @override
   * @param  {Object} params  The filters and order to apply to the results.
   * @return {Promise}
   */


  async list(params = {
    filters: {}
  }) {
    const {
      filters
    } = params;

    try {
      let results = [];
      await this.prepare("records", store => {
        createListRequest(this.cid, store, filters, _results => {
          // we have received all requested records that match the filters,
          // we now park them within current scope and hide the `_cid` attribute.
          for (const result of _results) {
            delete result["_cid"];
          }

          results = _results;
        });
      }); // The resulting list of records is sorted.
      // XXX: with some efforts, this could be fully implemented using IDB API.

      return params.order ? (0, _utils.sortObjects)(params.order, results) : results;
    } catch (e) {
      this._handleError("list", e);
    }
  }
  /**
   * Store the lastModified value into metadata store.
   *
   * @override
   * @param  {Number}  lastModified
   * @return {Promise}
   */


  async saveLastModified(lastModified) {
    const value = parseInt(lastModified, 10) || null;

    try {
      await this.prepare("timestamps", store => store.put({
        cid: this.cid,
        value
      }), {
        mode: "readwrite"
      });
      return value;
    } catch (e) {
      this._handleError("saveLastModified", e);
    }
  }
  /**
   * Retrieve saved lastModified value.
   *
   * @override
   * @return {Promise}
   */


  async getLastModified() {
    try {
      let entry = null;
      await this.prepare("timestamps", store => {
        store.get(this.cid).onsuccess = e => entry = e.target.result;
      });
      return entry ? entry.value : null;
    } catch (e) {
      this._handleError("getLastModified", e);
    }
  }
  /**
   * Load a dump of records exported from a server.
   *
   * @deprecated Use {@link importBulk} instead.
   * @abstract
   * @param  {Array} records The records to load.
   * @return {Promise}
   */


  async loadDump(records) {
    return this.importBulk(records);
  }
  /**
   * Load records in bulk that were exported from a server.
   *
   * @abstract
   * @param  {Array} records The records to load.
   * @return {Promise}
   */


  async importBulk(records) {
    try {
      await this.execute(transaction => {
        // Since the put operations are asynchronous, we chain
        // them together. The last one will be waited for the
        // `transaction.oncomplete` callback. (see #execute())
        let i = 0;
        putNext();

        function putNext() {
          if (i == records.length) {
            return;
          } // On error, `transaction.onerror` is called.


          transaction.update(records[i]).onsuccess = putNext;
          ++i;
        }
      });
      const previousLastModified = await this.getLastModified();
      const lastModified = Math.max(...records.map(record => record.last_modified));

      if (lastModified > previousLastModified) {
        await this.saveLastModified(lastModified);
      }

      return records;
    } catch (e) {
      this._handleError("importBulk", e);
    }
  }

  async saveMetadata(metadata) {
    try {
      await this.prepare("collections", store => store.put({
        cid: this.cid,
        metadata
      }), {
        mode: "readwrite"
      });
      return metadata;
    } catch (e) {
      this._handleError("saveMetadata", e);
    }
  }

  async getMetadata() {
    try {
      let entry = null;
      await this.prepare("collections", store => {
        store.get(this.cid).onsuccess = e => entry = e.target.result;
      });
      return entry ? entry.metadata : null;
    } catch (e) {
      this._handleError("getMetadata", e);
    }
  }

}
/**
 * IDB transaction proxy.
 *
 * @param  {IDB} adapter        The call IDB adapter
 * @param  {IDBStore} store     The IndexedDB database store.
 * @param  {Array}    preloaded The list of records to make available to
 *                              get() (default: []).
 * @return {Object}
 */


exports.default = IDB;

function transactionProxy(adapter, store, preloaded = []) {
  const _cid = adapter.cid;
  return {
    create(record) {
      store.add({ ...record,
        _cid
      });
    },

    update(record) {
      return store.put({ ...record,
        _cid
      });
    },

    delete(id) {
      store.delete([_cid, id]);
    },

    get(id) {
      return preloaded[id];
    }

  };
}
/**
 * Up to version 10.X of kinto.js, each collection had its own collection.
 * The database name was `${bid}/${cid}` (eg. `"blocklists/certificates"`)
 * and contained only one store with the same name.
 */


async function migrationRequired(dbName) {
  let exists = true;
  const db = await open(dbName, {
    version: 1,
    onupgradeneeded: event => {
      exists = false;
    }
  }); // Check that the DB we're looking at is really a legacy one,
  // and not some remainder of the open() operation above.

  exists &= db.objectStoreNames.contains("__meta__") && db.objectStoreNames.contains(dbName);

  if (!exists) {
    db.close(); // Testing the existence creates it, so delete it :)

    await deleteDatabase(dbName);
    return null;
  }

  console.warn(`${dbName}: old IndexedDB database found.`);

  try {
    // Scan all records.
    let records;
    await execute(db, dbName, store => {
      store.openCursor().onsuccess = cursorHandlers.all({}, res => records = res);
    });
    console.log(`${dbName}: found ${records.length} records.`); // Check if there's a entry for this.

    let timestamp = null;
    await execute(db, "__meta__", store => {
      store.get(`${dbName}-lastModified`).onsuccess = e => {
        timestamp = e.target.result ? e.target.result.value : null;
      };
    }); // Some previous versions, also used to store the timestamps without prefix.

    if (!timestamp) {
      await execute(db, "__meta__", store => {
        store.get("lastModified").onsuccess = e => {
          timestamp = e.target.result ? e.target.result.value : null;
        };
      });
    }

    console.log(`${dbName}: ${timestamp ? "found" : "no"} timestamp.`); // Those will be inserted in the new database/schema.

    return {
      records,
      timestamp
    };
  } catch (e) {
    console.error("Error occured during migration", e);
    return null;
  } finally {
    db.close();
  }
}

},{"../utils":7,"./base.js":5}],5:[function(require,module,exports){
"use strict";
/**
 * Base db adapter.
 *
 * @abstract
 */

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;

class BaseAdapter {
  /**
   * Deletes every records present in the database.
   *
   * @abstract
   * @return {Promise}
   */
  clear() {
    throw new Error("Not Implemented.");
  }
  /**
   * Executes a batch of operations within a single transaction.
   *
   * @abstract
   * @param  {Function} callback The operation callback.
   * @param  {Object}   options  The options object.
   * @return {Promise}
   */


  execute(callback, options = {
    preload: []
  }) {
    throw new Error("Not Implemented.");
  }
  /**
   * Retrieve a record by its primary key from the database.
   *
   * @abstract
   * @param  {String} id The record id.
   * @return {Promise}
   */


  get(id) {
    throw new Error("Not Implemented.");
  }
  /**
   * Lists all records from the database.
   *
   * @abstract
   * @param  {Object} params  The filters and order to apply to the results.
   * @return {Promise}
   */


  list(params = {
    filters: {},
    order: ""
  }) {
    throw new Error("Not Implemented.");
  }
  /**
   * Store the lastModified value.
   *
   * @abstract
   * @param  {Number}  lastModified
   * @return {Promise}
   */


  saveLastModified(lastModified) {
    throw new Error("Not Implemented.");
  }
  /**
   * Retrieve saved lastModified value.
   *
   * @abstract
   * @return {Promise}
   */


  getLastModified() {
    throw new Error("Not Implemented.");
  }
  /**
   * Load records in bulk that were exported from a server.
   *
   * @abstract
   * @param  {Array} records The records to load.
   * @return {Promise}
   */


  importBulk(records) {
    throw new Error("Not Implemented.");
  }
  /**
   * Load a dump of records exported from a server.
   *
   * @deprecated Use {@link importBulk} instead.
   * @abstract
   * @param  {Array} records The records to load.
   * @return {Promise}
   */


  loadDump(records) {
    throw new Error("Not Implemented.");
  }

  saveMetadata(metadata) {
    throw new Error("Not Implemented.");
  }

  getMetadata() {
    throw new Error("Not Implemented.");
  }

}

exports.default = BaseAdapter;

},{}],6:[function(require,module,exports){
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.recordsEqual = recordsEqual;
exports.createKeyValueStoreIdSchema = createKeyValueStoreIdSchema;
exports.CollectionTransaction = exports.default = exports.ServerWasFlushedError = exports.SyncResultObject = void 0;

var _base = _interopRequireDefault(require("./adapters/base"));

var _IDB = _interopRequireDefault(require("./adapters/IDB"));

var _utils = require("./utils");

var _uuid = require("uuid");

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

const RECORD_FIELDS_TO_CLEAN = ["_status"];
const AVAILABLE_HOOKS = ["incoming-changes"];
const IMPORT_CHUNK_SIZE = 200;
/**
 * Compare two records omitting local fields and synchronization
 * attributes (like _status and last_modified)
 * @param {Object} a    A record to compare.
 * @param {Object} b    A record to compare.
 * @param {Array} localFields Additional fields to ignore during the comparison
 * @return {boolean}
 */

function recordsEqual(a, b, localFields = []) {
  const fieldsToClean = RECORD_FIELDS_TO_CLEAN.concat(["last_modified"]).concat(localFields);

  const cleanLocal = r => (0, _utils.omitKeys)(r, fieldsToClean);

  return (0, _utils.deepEqual)(cleanLocal(a), cleanLocal(b));
}
/**
 * Synchronization result object.
 */


class SyncResultObject {
  /**
   * Public constructor.
   */
  constructor() {
    /**
     * Current synchronization result status; becomes `false` when conflicts or
     * errors are registered.
     * @type {Boolean}
     */
    this.lastModified = null;
    this._lists = {};
    ["errors", "created", "updated", "deleted", "published", "conflicts", "skipped", "resolved", "void"].forEach(l => this._lists[l] = []);
    this._cached = {};
  }
  /**
   * Adds entries for a given result type.
   *
   * @param {String} type    The result type.
   * @param {Array}  entries The result entries.
   * @return {SyncResultObject}
   */


  add(type, entries) {
    if (!Array.isArray(this._lists[type])) {
      console.warn(`Unknown type "${type}"`);
      return;
    }

    if (!Array.isArray(entries)) {
      entries = [entries];
    }

    this._lists[type] = this._lists[type].concat(entries);
    delete this._cached[type];
    return this;
  }

  get ok() {
    return this.errors.length + this.conflicts.length === 0;
  }

  get errors() {
    return this._lists["errors"];
  }

  get conflicts() {
    return this._lists["conflicts"];
  }

  get skipped() {
    return this._deduplicate("skipped");
  }

  get resolved() {
    return this._deduplicate("resolved");
  }

  get created() {
    return this._deduplicate("created");
  }

  get updated() {
    return this._deduplicate("updated");
  }

  get deleted() {
    return this._deduplicate("deleted");
  }

  get published() {
    return this._deduplicate("published");
  }

  _deduplicate(list) {
    if (!(list in this._cached)) {
      // Deduplicate entries by id. If the values don't have `id` attribute, just
      // keep all.
      const recordsWithoutId = new Set();
      const recordsById = new Map();

      this._lists[list].forEach(record => {
        if (!record.id) {
          recordsWithoutId.add(record);
        } else {
          recordsById.set(record.id, record);
        }
      });

      this._cached[list] = Array.from(recordsById.values()).concat(Array.from(recordsWithoutId));
    }

    return this._cached[list];
  }
  /**
   * Reinitializes result entries for a given result type.
   *
   * @param  {String} type The result type.
   * @return {SyncResultObject}
   */


  reset(type) {
    this._lists[type] = [];
    delete this._cached[type];
    return this;
  }

  toObject() {
    // Only used in tests.
    return {
      ok: this.ok,
      lastModified: this.lastModified,
      errors: this.errors,
      created: this.created,
      updated: this.updated,
      deleted: this.deleted,
      skipped: this.skipped,
      published: this.published,
      conflicts: this.conflicts,
      resolved: this.resolved
    };
  }

}

exports.SyncResultObject = SyncResultObject;

class ServerWasFlushedError extends Error {
  constructor(clientTimestamp, serverTimestamp, message) {
    super(message);

    if (Error.captureStackTrace) {
      Error.captureStackTrace(this, ServerWasFlushedError);
    }

    this.clientTimestamp = clientTimestamp;
    this.serverTimestamp = serverTimestamp;
  }

}

exports.ServerWasFlushedError = ServerWasFlushedError;

function createUUIDSchema() {
  return {
    generate() {
      return (0, _uuid.v4)();
    },

    validate(id) {
      return typeof id == "string" && _utils.RE_RECORD_ID.test(id);
    }

  };
}
/**
 * IDSchema for when using kinto.js as a key-value store.
 * Using this IDSchema requires you to set a property as the id.
 * This will be the property used to retrieve this record.
 *
 * @example
 * const exampleCollection = db.collection("example", { idSchema: createKeyValueStoreIdSchema() })
 * await exampleCollection.create({ title: "How to tie a tie", favoriteColor: "blue", id: "user123" }, { useRecordId: true })
 * await exampleCollection.getAny("user123")
 */


function createKeyValueStoreIdSchema() {
  return {
    generate() {
      throw new Error("createKeyValueStoreIdSchema() does not generate an id");
    },

    validate() {
      return true;
    }

  };
}

function markStatus(record, status) {
  return { ...record,
    _status: status
  };
}

function markDeleted(record) {
  return markStatus(record, "deleted");
}

function markSynced(record) {
  return markStatus(record, "synced");
}
/**
 * Import a remote change into the local database.
 *
 * @param  {IDBTransactionProxy} transaction The transaction handler.
 * @param  {Object}              remote      The remote change object to import.
 * @param  {Array<String>}       localFields The list of fields that remain local.
 * @param  {String}              strategy    The {@link Collection.strategy}.
 * @return {Object}
 */


function importChange(transaction, remote, localFields, strategy) {
  const local = transaction.get(remote.id);

  if (!local) {
    // Not found locally but remote change is marked as deleted; skip to
    // avoid recreation.
    if (remote.deleted) {
      return {
        type: "skipped",
        data: remote
      };
    }

    const synced = markSynced(remote);
    transaction.create(synced);
    return {
      type: "created",
      data: synced
    };
  } // Apply remote changes on local record.


  const synced = { ...local,
    ...markSynced(remote)
  }; // With pull only, we don't need to compare records since we override them.

  if (strategy === Collection.strategy.PULL_ONLY) {
    if (remote.deleted) {
      transaction.delete(remote.id);
      return {
        type: "deleted",
        data: local
      };
    }

    transaction.update(synced);
    return {
      type: "updated",
      data: {
        old: local,
        new: synced
      }
    };
  } // With other sync strategies, we detect conflicts,
  // by comparing local and remote, ignoring local fields.


  const isIdentical = recordsEqual(local, remote, localFields); // Detect or ignore conflicts if record has also been modified locally.

  if (local._status !== "synced") {
    // Locally deleted, unsynced: scheduled for remote deletion.
    if (local._status === "deleted") {
      return {
        type: "skipped",
        data: local
      };
    }

    if (isIdentical) {
      // If records are identical, import anyway, so we bump the
      // local last_modified value from the server and set record
      // status to "synced".
      transaction.update(synced);
      return {
        type: "updated",
        data: {
          old: local,
          new: synced
        }
      };
    }

    if (local.last_modified !== undefined && local.last_modified === remote.last_modified) {
      // If our local version has the same last_modified as the remote
      // one, this represents an object that corresponds to a resolved
      // conflict. Our local version represents the final output, so
      // we keep that one. (No transaction operation to do.)
      // But if our last_modified is undefined,
      // that means we've created the same object locally as one on
      // the server, which *must* be a conflict.
      return {
        type: "void"
      };
    }

    return {
      type: "conflicts",
      data: {
        type: "incoming",
        local: local,
        remote: remote
      }
    };
  } // Local record was synced.


  if (remote.deleted) {
    transaction.delete(remote.id);
    return {
      type: "deleted",
      data: local
    };
  } // Import locally.


  transaction.update(synced); // if identical, simply exclude it from all SyncResultObject lists

  const type = isIdentical ? "void" : "updated";
  return {
    type,
    data: {
      old: local,
      new: synced
    }
  };
}
/**
 * Abstracts a collection of records stored in the local database, providing
 * CRUD operations and synchronization helpers.
 */


class Collection {
  /**
   * Constructor.
   *
   * Options:
   * - `{BaseAdapter} adapter` The DB adapter (default: `IDB`)
   *
   * @param  {String} bucket  The bucket identifier.
   * @param  {String} name    The collection name.
   * @param  {Api}    api     The Api instance.
   * @param  {Object} options The options object.
   */
  constructor(bucket, name, api, options = {}) {
    this._bucket = bucket;
    this._name = name;
    this._lastModified = null;
    const DBAdapter = options.adapter || _IDB.default;

    if (!DBAdapter) {
      throw new Error("No adapter provided");
    }

    const db = new DBAdapter(`${bucket}/${name}`, options.adapterOptions);

    if (!(db instanceof _base.default)) {
      throw new Error("Unsupported adapter.");
    } // public properties

    /**
     * The db adapter instance
     * @type {BaseAdapter}
     */


    this.db = db;
    /**
     * The Api instance.
     * @type {KintoClient}
     */

    this.api = api;
    /**
     * The event emitter instance.
     * @type {EventEmitter}
     */

    this.events = options.events;
    /**
     * The IdSchema instance.
     * @type {Object}
     */

    this.idSchema = this._validateIdSchema(options.idSchema);
    /**
     * The list of remote transformers.
     * @type {Array}
     */

    this.remoteTransformers = this._validateRemoteTransformers(options.remoteTransformers);
    /**
     * The list of hooks.
     * @type {Object}
     */

    this.hooks = this._validateHooks(options.hooks);
    /**
     * The list of fields names that will remain local.
     * @type {Array}
     */

    this.localFields = options.localFields || [];
  }
  /**
   * The collection name.
   * @type {String}
   */


  get name() {
    return this._name;
  }
  /**
   * The bucket name.
   * @type {String}
   */


  get bucket() {
    return this._bucket;
  }
  /**
   * The last modified timestamp.
   * @type {Number}
   */


  get lastModified() {
    return this._lastModified;
  }
  /**
   * Synchronization strategies. Available strategies are:
   *
   * - `MANUAL`: Conflicts will be reported in a dedicated array.
   * - `SERVER_WINS`: Conflicts are resolved using remote data.
   * - `CLIENT_WINS`: Conflicts are resolved using local data.
   *
   * @type {Object}
   */


  static get strategy() {
    return {
      CLIENT_WINS: "client_wins",
      SERVER_WINS: "server_wins",
      PULL_ONLY: "pull_only",
      MANUAL: "manual"
    };
  }
  /**
   * Validates an idSchema.
   *
   * @param  {Object|undefined} idSchema
   * @return {Object}
   */


  _validateIdSchema(idSchema) {
    if (typeof idSchema === "undefined") {
      return createUUIDSchema();
    }

    if (typeof idSchema !== "object") {
      throw new Error("idSchema must be an object.");
    } else if (typeof idSchema.generate !== "function") {
      throw new Error("idSchema must provide a generate function.");
    } else if (typeof idSchema.validate !== "function") {
      throw new Error("idSchema must provide a validate function.");
    }

    return idSchema;
  }
  /**
   * Validates a list of remote transformers.
   *
   * @param  {Array|undefined} remoteTransformers
   * @return {Array}
   */


  _validateRemoteTransformers(remoteTransformers) {
    if (typeof remoteTransformers === "undefined") {
      return [];
    }

    if (!Array.isArray(remoteTransformers)) {
      throw new Error("remoteTransformers should be an array.");
    }

    return remoteTransformers.map(transformer => {
      if (typeof transformer !== "object") {
        throw new Error("A transformer must be an object.");
      } else if (typeof transformer.encode !== "function") {
        throw new Error("A transformer must provide an encode function.");
      } else if (typeof transformer.decode !== "function") {
        throw new Error("A transformer must provide a decode function.");
      }

      return transformer;
    });
  }
  /**
   * Validate the passed hook is correct.
   *
   * @param {Array|undefined} hook.
   * @return {Array}
   **/


  _validateHook(hook) {
    if (!Array.isArray(hook)) {
      throw new Error("A hook definition should be an array of functions.");
    }

    return hook.map(fn => {
      if (typeof fn !== "function") {
        throw new Error("A hook definition should be an array of functions.");
      }

      return fn;
    });
  }
  /**
   * Validates a list of hooks.
   *
   * @param  {Object|undefined} hooks
   * @return {Object}
   */


  _validateHooks(hooks) {
    if (typeof hooks === "undefined") {
      return {};
    }

    if (Array.isArray(hooks)) {
      throw new Error("hooks should be an object, not an array.");
    }

    if (typeof hooks !== "object") {
      throw new Error("hooks should be an object.");
    }

    const validatedHooks = {};

    for (const hook in hooks) {
      if (!AVAILABLE_HOOKS.includes(hook)) {
        throw new Error("The hook should be one of " + AVAILABLE_HOOKS.join(", "));
      }

      validatedHooks[hook] = this._validateHook(hooks[hook]);
    }

    return validatedHooks;
  }
  /**
   * Deletes every records in the current collection and marks the collection as
   * never synced.
   *
   * @return {Promise}
   */


  async clear() {
    await this.db.clear();
    await this.db.saveMetadata(null);
    await this.db.saveLastModified(null);
    return {
      data: [],
      permissions: {}
    };
  }
  /**
   * Encodes a record.
   *
   * @param  {String} type   Either "remote" or "local".
   * @param  {Object} record The record object to encode.
   * @return {Promise}
   */


  _encodeRecord(type, record) {
    if (!this[`${type}Transformers`].length) {
      return Promise.resolve(record);
    }

    return (0, _utils.waterfall)(this[`${type}Transformers`].map(transformer => {
      return record => transformer.encode(record);
    }), record);
  }
  /**
   * Decodes a record.
   *
   * @param  {String} type   Either "remote" or "local".
   * @param  {Object} record The record object to decode.
   * @return {Promise}
   */


  _decodeRecord(type, record) {
    if (!this[`${type}Transformers`].length) {
      return Promise.resolve(record);
    }

    return (0, _utils.waterfall)(this[`${type}Transformers`].reverse().map(transformer => {
      return record => transformer.decode(record);
    }), record);
  }
  /**
   * Adds a record to the local database, asserting that none
   * already exist with this ID.
   *
   * Note: If either the `useRecordId` or `synced` options are true, then the
   * record object must contain the id field to be validated. If none of these
   * options are true, an id is generated using the current IdSchema; in this
   * case, the record passed must not have an id.
   *
   * Options:
   * - {Boolean} synced       Sets record status to "synced" (default: `false`).
   * - {Boolean} useRecordId  Forces the `id` field from the record to be used,
   *                          instead of one that is generated automatically
   *                          (default: `false`).
   *
   * @param  {Object} record
   * @param  {Object} options
   * @return {Promise}
   */


  create(record, options = {
    useRecordId: false,
    synced: false
  }) {
    // Validate the record and its ID (if any), even though this
    // validation is also done in the CollectionTransaction method,
    // because we need to pass the ID to preloadIds.
    const reject = msg => Promise.reject(new Error(msg));

    if (typeof record !== "object") {
      return reject("Record is not an object.");
    }

    if ((options.synced || options.useRecordId) && !Object.prototype.hasOwnProperty.call(record, "id")) {
      return reject("Missing required Id; synced and useRecordId options require one");
    }

    if (!options.synced && !options.useRecordId && Object.prototype.hasOwnProperty.call(record, "id")) {
      return reject("Extraneous Id; can't create a record having one set.");
    }

    const newRecord = { ...record,
      id: options.synced || options.useRecordId ? record.id : this.idSchema.generate(record),
      _status: options.synced ? "synced" : "created"
    };

    if (!this.idSchema.validate(newRecord.id)) {
      return reject(`Invalid Id: ${newRecord.id}`);
    }

    return this.execute(txn => txn.create(newRecord), {
      preloadIds: [newRecord.id]
    }).catch(err => {
      if (options.useRecordId) {
        throw new Error("Couldn't create record. It may have been virtually deleted.");
      }

      throw err;
    });
  }
  /**
   * Like {@link CollectionTransaction#update}, but wrapped in its own transaction.
   *
   * Options:
   * - {Boolean} synced: Sets record status to "synced" (default: false)
   * - {Boolean} patch:  Extends the existing record instead of overwriting it
   *   (default: false)
   *
   * @param  {Object} record
   * @param  {Object} options
   * @return {Promise}
   */


  update(record, options = {
    synced: false,
    patch: false
  }) {
    // Validate the record and its ID, even though this validation is
    // also done in the CollectionTransaction method, because we need
    // to pass the ID to preloadIds.
    if (typeof record !== "object") {
      return Promise.reject(new Error("Record is not an object."));
    }

    if (!Object.prototype.hasOwnProperty.call(record, "id")) {
      return Promise.reject(new Error("Cannot update a record missing id."));
    }

    if (!this.idSchema.validate(record.id)) {
      return Promise.reject(new Error(`Invalid Id: ${record.id}`));
    }

    return this.execute(txn => txn.update(record, options), {
      preloadIds: [record.id]
    });
  }
  /**
   * Like {@link CollectionTransaction#upsert}, but wrapped in its own transaction.
   *
   * @param  {Object} record
   * @return {Promise}
   */


  upsert(record) {
    // Validate the record and its ID, even though this validation is
    // also done in the CollectionTransaction method, because we need
    // to pass the ID to preloadIds.
    if (typeof record !== "object") {
      return Promise.reject(new Error("Record is not an object."));
    }

    if (!Object.prototype.hasOwnProperty.call(record, "id")) {
      return Promise.reject(new Error("Cannot update a record missing id."));
    }

    if (!this.idSchema.validate(record.id)) {
      return Promise.reject(new Error(`Invalid Id: ${record.id}`));
    }

    return this.execute(txn => txn.upsert(record), {
      preloadIds: [record.id]
    });
  }
  /**
   * Like {@link CollectionTransaction#get}, but wrapped in its own transaction.
   *
   * Options:
   * - {Boolean} includeDeleted: Include virtually deleted records.
   *
   * @param  {String} id
   * @param  {Object} options
   * @return {Promise}
   */


  get(id, options = {
    includeDeleted: false
  }) {
    return this.execute(txn => txn.get(id, options), {
      preloadIds: [id]
    });
  }
  /**
   * Like {@link CollectionTransaction#getAny}, but wrapped in its own transaction.
   *
   * @param  {String} id
   * @return {Promise}
   */


  getAny(id) {
    return this.execute(txn => txn.getAny(id), {
      preloadIds: [id]
    });
  }
  /**
   * Same as {@link Collection#delete}, but wrapped in its own transaction.
   *
   * Options:
   * - {Boolean} virtual: When set to `true`, doesn't actually delete the record,
   *   update its `_status` attribute to `deleted` instead (default: true)
   *
   * @param  {String} id       The record's Id.
   * @param  {Object} options  The options object.
   * @return {Promise}
   */


  delete(id, options = {
    virtual: true
  }) {
    return this.execute(transaction => {
      return transaction.delete(id, options);
    }, {
      preloadIds: [id]
    });
  }
  /**
   * Same as {@link Collection#deleteAll}, but wrapped in its own transaction, execulding the parameter.
   *
   * @return {Promise}
   */


  async deleteAll() {
    const {
      data
    } = await this.list({}, {
      includeDeleted: false
    });
    const recordIds = data.map(record => record.id);
    return this.execute(transaction => {
      return transaction.deleteAll(recordIds);
    }, {
      preloadIds: recordIds
    });
  }
  /**
   * The same as {@link CollectionTransaction#deleteAny}, but wrapped
   * in its own transaction.
   *
   * @param  {String} id       The record's Id.
   * @return {Promise}
   */


  deleteAny(id) {
    return this.execute(txn => txn.deleteAny(id), {
      preloadIds: [id]
    });
  }
  /**
   * Lists records from the local database.
   *
   * Params:
   * - {Object} filters Filter the results (default: `{}`).
   * - {String} order   The order to apply   (default: `-last_modified`).
   *
   * Options:
   * - {Boolean} includeDeleted: Include virtually deleted records.
   *
   * @param  {Object} params  The filters and order to apply to the results.
   * @param  {Object} options The options object.
   * @return {Promise}
   */


  async list(params = {}, options = {
    includeDeleted: false
  }) {
    params = {
      order: "-last_modified",
      filters: {},
      ...params
    };
    const results = await this.db.list(params);
    let data = results;

    if (!options.includeDeleted) {
      data = results.filter(record => record._status !== "deleted");
    }

    return {
      data,
      permissions: {}
    };
  }
  /**
   * Imports remote changes into the local database.
   * This method is in charge of detecting the conflicts, and resolve them
   * according to the specified strategy.
   * @param  {SyncResultObject} syncResultObject The sync result object.
   * @param  {Array}            decodedChanges   The list of changes to import in the local database.
   * @param  {String}           strategy         The {@link Collection.strategy} (default: MANUAL)
   * @return {Promise}
   */


  async importChanges(syncResultObject, decodedChanges, strategy = Collection.strategy.MANUAL) {
    // Retrieve records matching change ids.
    try {
      for (let i = 0; i < decodedChanges.length; i += IMPORT_CHUNK_SIZE) {
        const slice = decodedChanges.slice(i, i + IMPORT_CHUNK_SIZE);
        const {
          imports,
          resolved
        } = await this.db.execute(transaction => {
          const imports = slice.map(remote => {
            // Store remote change into local database.
            return importChange(transaction, remote, this.localFields, strategy);
          });
          const conflicts = imports.filter(i => i.type === "conflicts").map(i => i.data);

          const resolved = this._handleConflicts(transaction, conflicts, strategy);

          return {
            imports,
            resolved
          };
        }, {
          preload: slice.map(record => record.id)
        }); // Lists of created/updated/deleted records

        imports.forEach(({
          type,
          data
        }) => syncResultObject.add(type, data)); // Automatically resolved conflicts (if not manual)

        if (resolved.length > 0) {
          syncResultObject.reset("conflicts").add("resolved", resolved);
        }
      }
    } catch (err) {
      const data = {
        type: "incoming",
        message: err.message,
        stack: err.stack
      }; // XXX one error of the whole transaction instead of per atomic op

      syncResultObject.add("errors", data);
    }

    return syncResultObject;
  }
  /**
   * Imports the responses of pushed changes into the local database.
   * Basically it stores the timestamp assigned by the server into the local
   * database.
   * @param  {SyncResultObject} syncResultObject The sync result object.
   * @param  {Array}            toApplyLocally   The list of changes to import in the local database.
   * @param  {Array}            conflicts        The list of conflicts that have to be resolved.
   * @param  {String}           strategy         The {@link Collection.strategy}.
   * @return {Promise}
   */


  async _applyPushedResults(syncResultObject, toApplyLocally, conflicts, strategy = Collection.strategy.MANUAL) {
    const toDeleteLocally = toApplyLocally.filter(r => r.deleted);
    const toUpdateLocally = toApplyLocally.filter(r => !r.deleted);
    const {
      published,
      resolved
    } = await this.db.execute(transaction => {
      const updated = toUpdateLocally.map(record => {
        const synced = markSynced(record);
        transaction.update(synced);
        return synced;
      });
      const deleted = toDeleteLocally.map(record => {
        transaction.delete(record.id); // Amend result data with the deleted attribute set

        return {
          id: record.id,
          deleted: true
        };
      });
      const published = updated.concat(deleted); // Handle conflicts, if any

      const resolved = this._handleConflicts(transaction, conflicts, strategy);

      return {
        published,
        resolved
      };
    });
    syncResultObject.add("published", published);

    if (resolved.length > 0) {
      syncResultObject.reset("conflicts").reset("resolved").add("resolved", resolved);
    }

    return syncResultObject;
  }
  /**
   * Handles synchronization conflicts according to specified strategy.
   *
   * @param  {SyncResultObject} result    The sync result object.
   * @param  {String}           strategy  The {@link Collection.strategy}.
   * @return {Promise<Array<Object>>} The resolved conflicts, as an
   *    array of {accepted, rejected} objects
   */


  _handleConflicts(transaction, conflicts, strategy) {
    if (strategy === Collection.strategy.MANUAL) {
      return [];
    }

    return conflicts.map(conflict => {
      const resolution = strategy === Collection.strategy.CLIENT_WINS ? conflict.local : conflict.remote;
      const rejected = strategy === Collection.strategy.CLIENT_WINS ? conflict.remote : conflict.local;
      let accepted, status, id;

      if (resolution === null) {
        // We "resolved" with the server-side deletion. Delete locally.
        // This only happens during SERVER_WINS because the local
        // version of a record can never be null.
        // We can get "null" from the remote side if we got a conflict
        // and there is no remote version available; see kinto-http.js
        // batch.js:aggregate.
        transaction.delete(conflict.local.id);
        accepted = null; // The record was deleted, but that status is "synced" with
        // the server, so we don't need to push the change.

        status = "synced";
        id = conflict.local.id;
      } else {
        const updated = this._resolveRaw(conflict, resolution);

        transaction.update(updated);
        accepted = updated;
        status = updated._status;
        id = updated.id;
      }

      return {
        rejected,
        accepted,
        id,
        _status: status
      };
    });
  }
  /**
   * Execute a bunch of operations in a transaction.
   *
   * This transaction should be atomic -- either all of its operations
   * will succeed, or none will.
   *
   * The argument to this function is itself a function which will be
   * called with a {@link CollectionTransaction}. Collection methods
   * are available on this transaction, but instead of returning
   * promises, they are synchronous. execute() returns a Promise whose
   * value will be the return value of the provided function.
   *
   * Most operations will require access to the record itself, which
   * must be preloaded by passing its ID in the preloadIds option.
   *
   * Options:
   * - {Array} preloadIds: list of IDs to fetch at the beginning of
   *   the transaction
   *
   * @return {Promise} Resolves with the result of the given function
   *    when the transaction commits.
   */


  execute(doOperations, {
    preloadIds = []
  } = {}) {
    for (const id of preloadIds) {
      if (!this.idSchema.validate(id)) {
        return Promise.reject(Error(`Invalid Id: ${id}`));
      }
    }

    return this.db.execute(transaction => {
      const txn = new CollectionTransaction(this, transaction);
      const result = doOperations(txn);
      txn.emitEvents();
      return result;
    }, {
      preload: preloadIds
    });
  }
  /**
   * Resets the local records as if they were never synced; existing records are
   * marked as newly created, deleted records are dropped.
   *
   * A next call to {@link Collection.sync} will thus republish the whole
   * content of the local collection to the server.
   *
   * @return {Promise} Resolves with the number of processed records.
   */


  async resetSyncStatus() {
    const unsynced = await this.list({
      filters: {
        _status: ["deleted", "synced"]
      },
      order: ""
    }, {
      includeDeleted: true
    });
    await this.db.execute(transaction => {
      unsynced.data.forEach(record => {
        if (record._status === "deleted") {
          // Garbage collect deleted records.
          transaction.delete(record.id);
        } else {
          // Records that were synced become «created».
          transaction.update({ ...record,
            last_modified: undefined,
            _status: "created"
          });
        }
      });
    });
    this._lastModified = null;
    await this.db.saveLastModified(null);
    return unsynced.data.length;
  }
  /**
   * Returns an object containing two lists:
   *
   * - `toDelete`: unsynced deleted records we can safely delete;
   * - `toSync`: local updates to send to the server.
   *
   * @return {Promise}
   */


  async gatherLocalChanges() {
    const unsynced = await this.list({
      filters: {
        _status: ["created", "updated"]
      },
      order: ""
    });
    const deleted = await this.list({
      filters: {
        _status: "deleted"
      },
      order: ""
    }, {
      includeDeleted: true
    });
    return await Promise.all(unsynced.data.concat(deleted.data).map(this._encodeRecord.bind(this, "remote")));
  }
  /**
   * Fetch remote changes, import them to the local database, and handle
   * conflicts according to `options.strategy`. Then, updates the passed
   * {@link SyncResultObject} with import results.
   *
   * Options:
   * - {String} strategy: The selected sync strategy.
   * - {String} expectedTimestamp: A timestamp to use as a "cache busting" query parameter.
   * - {Array<String>} exclude: A list of record ids to exclude from pull.
   * - {Object} headers: The HTTP headers to use in the request.
   * - {int} retry: The number of retries to do if the HTTP request fails.
   * - {int} lastModified: The timestamp to use in `?_since` query.
   *
   * @param  {KintoClient.Collection} client           Kinto client Collection instance.
   * @param  {SyncResultObject}       syncResultObject The sync result object.
   * @param  {Object}                 options          The options object.
   * @return {Promise}
   */


  async pullChanges(client, syncResultObject, options = {}) {
    if (!syncResultObject.ok) {
      return syncResultObject;
    }

    const since = this.lastModified ? this.lastModified : await this.db.getLastModified();
    options = {
      strategy: Collection.strategy.MANUAL,
      lastModified: since,
      headers: {},
      ...options
    }; // Optionally ignore some records when pulling for changes.
    // (avoid redownloading our own changes on last step of #sync())

    let filters;

    if (options.exclude) {
      // Limit the list of excluded records to the first 50 records in order
      // to remain under de-facto URL size limit (~2000 chars).
      // http://stackoverflow.com/questions/417142/what-is-the-maximum-length-of-a-url-in-different-browsers/417184#417184
      const exclude_id = options.exclude.slice(0, 50).map(r => r.id).join(",");
      filters = {
        exclude_id
      };
    }

    if (options.expectedTimestamp) {
      filters = { ...filters,
        _expected: options.expectedTimestamp
      };
    } // First fetch remote changes from the server


    const {
      data,
      last_modified
    } = await client.listRecords({
      // Since should be ETag (see https://github.com/Kinto/kinto.js/issues/356)
      since: options.lastModified ? `${options.lastModified}` : undefined,
      headers: options.headers,
      retry: options.retry,
      // Fetch every page by default (FIXME: option to limit pages, see #277)
      pages: Infinity,
      filters
    }); // last_modified is the ETag header value (string).
    // For retro-compatibility with first kinto.js versions
    // parse it to integer.

    const unquoted = last_modified ? parseInt(last_modified, 10) : undefined; // Check if server was flushed.
    // This is relevant for the Kinto demo server
    // (and thus for many new comers).

    const localSynced = options.lastModified;
    const serverChanged = unquoted > options.lastModified;
    const emptyCollection = data.length === 0;

    if (!options.exclude && localSynced && serverChanged && emptyCollection) {
      const e = new ServerWasFlushedError(localSynced, unquoted, "Server has been flushed. Client Side Timestamp: " + localSynced + " Server Side Timestamp: " + unquoted);
      throw e;
    } // Atomic updates are not sensible here because unquoted is not
    // computed as a function of syncResultObject.lastModified.
    // eslint-disable-next-line require-atomic-updates


    syncResultObject.lastModified = unquoted; // Decode incoming changes.

    const decodedChanges = await Promise.all(data.map(change => {
      return this._decodeRecord("remote", change);
    })); // Hook receives decoded records.

    const payload = {
      lastModified: unquoted,
      changes: decodedChanges
    };
    const afterHooks = await this.applyHook("incoming-changes", payload); // No change, nothing to import.

    if (afterHooks.changes.length > 0) {
      // Reflect these changes locally
      await this.importChanges(syncResultObject, afterHooks.changes, options.strategy);
    }

    return syncResultObject;
  }

  applyHook(hookName, payload) {
    if (typeof this.hooks[hookName] == "undefined") {
      return Promise.resolve(payload);
    }

    return (0, _utils.waterfall)(this.hooks[hookName].map(hook => {
      return record => {
        const result = hook(payload, this);
        const resultThenable = result && typeof result.then === "function";
        const resultChanges = result && Object.prototype.hasOwnProperty.call(result, "changes");

        if (!(resultThenable || resultChanges)) {
          throw new Error(`Invalid return value for hook: ${JSON.stringify(result)} has no 'then()' or 'changes' properties`);
        }

        return result;
      };
    }), payload);
  }
  /**
   * Publish local changes to the remote server and updates the passed
   * {@link SyncResultObject} with publication results.
   *
   * Options:
   * - {String} strategy: The selected sync strategy.
   * - {Object} headers: The HTTP headers to use in the request.
   * - {int} retry: The number of retries to do if the HTTP request fails.
   *
   * @param  {KintoClient.Collection} client           Kinto client Collection instance.
   * @param  {SyncResultObject}       syncResultObject The sync result object.
   * @param  {Object}                 changes          The change object.
   * @param  {Array}                  changes.toDelete The list of records to delete.
   * @param  {Array}                  changes.toSync   The list of records to create/update.
   * @param  {Object}                 options          The options object.
   * @return {Promise}
   */


  async pushChanges(client, changes, syncResultObject, options = {}) {
    if (!syncResultObject.ok) {
      return syncResultObject;
    }

    const safe = !options.strategy || options.strategy !== Collection.CLIENT_WINS;
    const toDelete = changes.filter(r => r._status == "deleted");
    const toSync = changes.filter(r => r._status != "deleted"); // Perform a batch request with every changes.

    const synced = await client.batch(batch => {
      toDelete.forEach(r => {
        // never published locally deleted records should not be pusblished
        if (r.last_modified) {
          batch.deleteRecord(r);
        }
      });
      toSync.forEach(r => {
        // Clean local fields (like _status) before sending to server.
        const published = this.cleanLocalFields(r);

        if (r._status === "created") {
          batch.createRecord(published);
        } else {
          batch.updateRecord(published);
        }
      });
    }, {
      headers: options.headers,
      retry: options.retry,
      safe,
      aggregate: true
    }); // Store outgoing errors into sync result object

    syncResultObject.add("errors", synced.errors.map(e => ({ ...e,
      type: "outgoing"
    }))); // Store outgoing conflicts into sync result object

    const conflicts = [];

    for (const {
      type,
      local,
      remote
    } of synced.conflicts) {
      // Note: we ensure that local data are actually available, as they may
      // be missing in the case of a published deletion.
      const safeLocal = local && local.data || {
        id: remote.id
      };
      const realLocal = await this._decodeRecord("remote", safeLocal); // We can get "null" from the remote side if we got a conflict
      // and there is no remote version available; see kinto-http.js
      // batch.js:aggregate.

      const realRemote = remote && (await this._decodeRecord("remote", remote));
      const conflict = {
        type,
        local: realLocal,
        remote: realRemote
      };
      conflicts.push(conflict);
    }

    syncResultObject.add("conflicts", conflicts); // Records that must be deleted are either deletions that were pushed
    // to server (published) or deleted records that were never pushed (skipped).

    const missingRemotely = synced.skipped.map(r => ({ ...r,
      deleted: true
    })); // For created and updated records, the last_modified coming from server
    // will be stored locally.
    // Reflect publication results locally using the response from
    // the batch request.

    const published = synced.published.map(c => c.data);
    const toApplyLocally = published.concat(missingRemotely); // Apply the decode transformers, if any

    const decoded = await Promise.all(toApplyLocally.map(record => {
      return this._decodeRecord("remote", record);
    })); // We have to update the local records with the responses of the server
    // (eg. last_modified values etc.).

    if (decoded.length > 0 || conflicts.length > 0) {
      await this._applyPushedResults(syncResultObject, decoded, conflicts, options.strategy);
    }

    return syncResultObject;
  }
  /**
   * Return a copy of the specified record without the local fields.
   *
   * @param  {Object} record  A record with potential local fields.
   * @return {Object}
   */


  cleanLocalFields(record) {
    const localKeys = RECORD_FIELDS_TO_CLEAN.concat(this.localFields);
    return (0, _utils.omitKeys)(record, localKeys);
  }
  /**
   * Resolves a conflict, updating local record according to proposed
   * resolution — keeping remote record `last_modified` value as a reference for
   * further batch sending.
   *
   * @param  {Object} conflict   The conflict object.
   * @param  {Object} resolution The proposed record.
   * @return {Promise}
   */


  resolve(conflict, resolution) {
    return this.db.execute(transaction => {
      const updated = this._resolveRaw(conflict, resolution);

      transaction.update(updated);
      return {
        data: updated,
        permissions: {}
      };
    });
  }
  /**
   * @private
   */


  _resolveRaw(conflict, resolution) {
    const resolved = { ...resolution,
      // Ensure local record has the latest authoritative timestamp
      last_modified: conflict.remote && conflict.remote.last_modified
    }; // If the resolution object is strictly equal to the
    // remote record, then we can mark it as synced locally.
    // Otherwise, mark it as updated (so that the resolution is pushed).

    const synced = (0, _utils.deepEqual)(resolved, conflict.remote);
    return markStatus(resolved, synced ? "synced" : "updated");
  }
  /**
   * Synchronize remote and local data. The promise will resolve with a
   * {@link SyncResultObject}, though will reject:
   *
   * - if the server is currently backed off;
   * - if the server has been detected flushed.
   *
   * Options:
   * - {Object} headers: HTTP headers to attach to outgoing requests.
   * - {String} expectedTimestamp: A timestamp to use as a "cache busting" query parameter.
   * - {Number} retry: Number of retries when server fails to process the request (default: 1).
   * - {Collection.strategy} strategy: See {@link Collection.strategy}.
   * - {Boolean} ignoreBackoff: Force synchronization even if server is currently
   *   backed off.
   * - {String} bucket: The remove bucket id to use (default: null)
   * - {String} collection: The remove collection id to use (default: null)
   * - {String} remote The remote Kinto server endpoint to use (default: null).
   *
   * @param  {Object} options Options.
   * @return {Promise}
   * @throws {Error} If an invalid remote option is passed.
   */


  async sync(options = {
    strategy: Collection.strategy.MANUAL,
    headers: {},
    retry: 1,
    ignoreBackoff: false,
    bucket: null,
    collection: null,
    remote: null,
    expectedTimestamp: null
  }) {
    options = { ...options,
      bucket: options.bucket || this.bucket,
      collection: options.collection || this.name
    };
    const previousRemote = this.api.remote;

    if (options.remote) {
      // Note: setting the remote ensures it's valid, throws when invalid.
      this.api.remote = options.remote;
    }

    if (!options.ignoreBackoff && this.api.backoff > 0) {
      const seconds = Math.ceil(this.api.backoff / 1000);
      return Promise.reject(new Error(`Server is asking clients to back off; retry in ${seconds}s or use the ignoreBackoff option.`));
    }

    const client = this.api.bucket(options.bucket).collection(options.collection);
    const result = new SyncResultObject();

    try {
      // Fetch collection metadata.
      await this.pullMetadata(client, options); // Fetch last changes from the server.

      await this.pullChanges(client, result, options);
      const {
        lastModified
      } = result;

      if (options.strategy != Collection.strategy.PULL_ONLY) {
        // Fetch local changes
        const toSync = await this.gatherLocalChanges(); // Publish local changes and pull local resolutions

        await this.pushChanges(client, toSync, result, options); // Publish local resolution of push conflicts to server (on CLIENT_WINS)

        const resolvedUnsynced = result.resolved.filter(r => r._status !== "synced");

        if (resolvedUnsynced.length > 0) {
          const resolvedEncoded = await Promise.all(resolvedUnsynced.map(resolution => {
            let record = resolution.accepted;

            if (record === null) {
              record = {
                id: resolution.id,
                _status: resolution._status
              };
            }

            return this._encodeRecord("remote", record);
          }));
          await this.pushChanges(client, resolvedEncoded, result, options);
        } // Perform a last pull to catch changes that occured after the last pull,
        // while local changes were pushed. Do not do it nothing was pushed.


        if (result.published.length > 0) {
          // Avoid redownloading our own changes during the last pull.
          const pullOpts = { ...options,
            lastModified,
            exclude: result.published
          };
          await this.pullChanges(client, result, pullOpts);
        }
      } // Don't persist lastModified value if any conflict or error occured


      if (result.ok) {
        // No conflict occured, persist collection's lastModified value
        this._lastModified = await this.db.saveLastModified(result.lastModified);
      }
    } catch (e) {
      this.events.emit("sync:error", { ...options,
        error: e
      });
      throw e;
    } finally {
      // Ensure API default remote is reverted if a custom one's been used
      this.api.remote = previousRemote;
    }

    this.events.emit("sync:success", { ...options,
      result
    });
    return result;
  }
  /**
   * Load a list of records already synced with the remote server.
   *
   * The local records which are unsynced or whose timestamp is either missing
   * or superior to those being loaded will be ignored.
   *
   * @deprecated Use {@link importBulk} instead.
   * @param  {Array} records The previously exported list of records to load.
   * @return {Promise} with the effectively imported records.
   */


  async loadDump(records) {
    return this.importBulk(records);
  }
  /**
   * Load a list of records already synced with the remote server.
   *
   * The local records which are unsynced or whose timestamp is either missing
   * or superior to those being loaded will be ignored.
   *
   * @param  {Array} records The previously exported list of records to load.
   * @return {Promise} with the effectively imported records.
   */


  async importBulk(records) {
    if (!Array.isArray(records)) {
      throw new Error("Records is not an array.");
    }

    for (const record of records) {
      if (!Object.prototype.hasOwnProperty.call(record, "id") || !this.idSchema.validate(record.id)) {
        throw new Error("Record has invalid ID: " + JSON.stringify(record));
      }

      if (!record.last_modified) {
        throw new Error("Record has no last_modified value: " + JSON.stringify(record));
      }
    } // Fetch all existing records from local database,
    // and skip those who are newer or not marked as synced.
    // XXX filter by status / ids in records


    const {
      data
    } = await this.list({}, {
      includeDeleted: true
    });
    const existingById = data.reduce((acc, record) => {
      acc[record.id] = record;
      return acc;
    }, {});
    const newRecords = records.filter(record => {
      const localRecord = existingById[record.id];
      const shouldKeep = // No local record with this id.
      localRecord === undefined || // Or local record is synced
      localRecord._status === "synced" && // And was synced from server
      localRecord.last_modified !== undefined && // And is older than imported one.
      record.last_modified > localRecord.last_modified;
      return shouldKeep;
    });
    return await this.db.importBulk(newRecords.map(markSynced));
  }

  async pullMetadata(client, options = {}) {
    const {
      expectedTimestamp,
      headers
    } = options;
    const query = expectedTimestamp ? {
      query: {
        _expected: expectedTimestamp
      }
    } : undefined;
    const metadata = await client.getData({ ...query,
      headers
    });
    return this.db.saveMetadata(metadata);
  }

  async metadata() {
    return this.db.getMetadata();
  }

}
/**
 * A Collection-oriented wrapper for an adapter's transaction.
 *
 * This defines the high-level functions available on a collection.
 * The collection itself offers functions of the same name. These will
 * perform just one operation in its own transaction.
 */


exports.default = Collection;

class CollectionTransaction {
  constructor(collection, adapterTransaction) {
    this.collection = collection;
    this.adapterTransaction = adapterTransaction;
    this._events = [];
  }

  _queueEvent(action, payload) {
    this._events.push({
      action,
      payload
    });
  }
  /**
   * Emit queued events, to be called once every transaction operations have
   * been executed successfully.
   */


  emitEvents() {
    for (const {
      action,
      payload
    } of this._events) {
      this.collection.events.emit(action, payload);
    }

    if (this._events.length > 0) {
      const targets = this._events.map(({
        action,
        payload
      }) => ({
        action,
        ...payload
      }));

      this.collection.events.emit("change", {
        targets
      });
    }

    this._events = [];
  }
  /**
   * Retrieve a record by its id from the local database, or
   * undefined if none exists.
   *
   * This will also return virtually deleted records.
   *
   * @param  {String} id
   * @return {Object}
   */


  getAny(id) {
    const record = this.adapterTransaction.get(id);
    return {
      data: record,
      permissions: {}
    };
  }
  /**
   * Retrieve a record by its id from the local database.
   *
   * Options:
   * - {Boolean} includeDeleted: Include virtually deleted records.
   *
   * @param  {String} id
   * @param  {Object} options
   * @return {Object}
   */


  get(id, options = {
    includeDeleted: false
  }) {
    const res = this.getAny(id);

    if (!res.data || !options.includeDeleted && res.data._status === "deleted") {
      throw new Error(`Record with id=${id} not found.`);
    }

    return res;
  }
  /**
   * Deletes a record from the local database.
   *
   * Options:
   * - {Boolean} virtual: When set to `true`, doesn't actually delete the record,
   *   update its `_status` attribute to `deleted` instead (default: true)
   *
   * @param  {String} id       The record's Id.
   * @param  {Object} options  The options object.
   * @return {Object}
   */


  delete(id, options = {
    virtual: true
  }) {
    // Ensure the record actually exists.
    const existing = this.adapterTransaction.get(id);
    const alreadyDeleted = existing && existing._status == "deleted";

    if (!existing || alreadyDeleted && options.virtual) {
      throw new Error(`Record with id=${id} not found.`);
    } // Virtual updates status.


    if (options.virtual) {
      this.adapterTransaction.update(markDeleted(existing));
    } else {
      // Delete for real.
      this.adapterTransaction.delete(id);
    }

    this._queueEvent("delete", {
      data: existing
    });

    return {
      data: existing,
      permissions: {}
    };
  }
  /**
   * Soft delete all records from the local database.
   *
   * @param  {Array} ids        Array of non-deleted Record Ids.
   * @return {Object}
   */


  deleteAll(ids) {
    const existingRecords = [];
    ids.forEach(id => {
      existingRecords.push(this.adapterTransaction.get(id));
      this.delete(id);
    });

    this._queueEvent("deleteAll", {
      data: existingRecords
    });

    return {
      data: existingRecords,
      permissions: {}
    };
  }
  /**
   * Deletes a record from the local database, if any exists.
   * Otherwise, do nothing.
   *
   * @param  {String} id       The record's Id.
   * @return {Object}
   */


  deleteAny(id) {
    const existing = this.adapterTransaction.get(id);

    if (existing) {
      this.adapterTransaction.update(markDeleted(existing));

      this._queueEvent("delete", {
        data: existing
      });
    }

    return {
      data: {
        id,
        ...existing
      },
      deleted: !!existing,
      permissions: {}
    };
  }
  /**
   * Adds a record to the local database, asserting that none
   * already exist with this ID.
   *
   * @param  {Object} record, which must contain an ID
   * @return {Object}
   */


  create(record) {
    if (typeof record !== "object") {
      throw new Error("Record is not an object.");
    }

    if (!Object.prototype.hasOwnProperty.call(record, "id")) {
      throw new Error("Cannot create a record missing id");
    }

    if (!this.collection.idSchema.validate(record.id)) {
      throw new Error(`Invalid Id: ${record.id}`);
    }

    this.adapterTransaction.create(record);

    this._queueEvent("create", {
      data: record
    });

    return {
      data: record,
      permissions: {}
    };
  }
  /**
   * Updates a record from the local database.
   *
   * Options:
   * - {Boolean} synced: Sets record status to "synced" (default: false)
   * - {Boolean} patch:  Extends the existing record instead of overwriting it
   *   (default: false)
   *
   * @param  {Object} record
   * @param  {Object} options
   * @return {Object}
   */


  update(record, options = {
    synced: false,
    patch: false
  }) {
    if (typeof record !== "object") {
      throw new Error("Record is not an object.");
    }

    if (!Object.prototype.hasOwnProperty.call(record, "id")) {
      throw new Error("Cannot update a record missing id.");
    }

    if (!this.collection.idSchema.validate(record.id)) {
      throw new Error(`Invalid Id: ${record.id}`);
    }

    const oldRecord = this.adapterTransaction.get(record.id);

    if (!oldRecord) {
      throw new Error(`Record with id=${record.id} not found.`);
    }

    const newRecord = options.patch ? { ...oldRecord,
      ...record
    } : record;

    const updated = this._updateRaw(oldRecord, newRecord, options);

    this.adapterTransaction.update(updated);

    this._queueEvent("update", {
      data: updated,
      oldRecord
    });

    return {
      data: updated,
      oldRecord,
      permissions: {}
    };
  }
  /**
   * Lower-level primitive for updating a record while respecting
   * _status and last_modified.
   *
   * @param  {Object} oldRecord: the record retrieved from the DB
   * @param  {Object} newRecord: the record to replace it with
   * @return {Object}
   */


  _updateRaw(oldRecord, newRecord, {
    synced = false
  } = {}) {
    const updated = { ...newRecord
    }; // Make sure to never loose the existing timestamp.

    if (oldRecord && oldRecord.last_modified && !updated.last_modified) {
      updated.last_modified = oldRecord.last_modified;
    } // If only local fields have changed, then keep record as synced.
    // If status is created, keep record as created.
    // If status is deleted, mark as updated.


    const isIdentical = oldRecord && recordsEqual(oldRecord, updated, this.collection.localFields);
    const keepSynced = isIdentical && oldRecord._status == "synced";
    const neverSynced = !oldRecord || oldRecord && oldRecord._status == "created";
    const newStatus = keepSynced || synced ? "synced" : neverSynced ? "created" : "updated";
    return markStatus(updated, newStatus);
  }
  /**
   * Upsert a record into the local database.
   *
   * This record must have an ID.
   *
   * If a record with this ID already exists, it will be replaced.
   * Otherwise, this record will be inserted.
   *
   * @param  {Object} record
   * @return {Object}
   */


  upsert(record) {
    if (typeof record !== "object") {
      throw new Error("Record is not an object.");
    }

    if (!Object.prototype.hasOwnProperty.call(record, "id")) {
      throw new Error("Cannot update a record missing id.");
    }

    if (!this.collection.idSchema.validate(record.id)) {
      throw new Error(`Invalid Id: ${record.id}`);
    }

    let oldRecord = this.adapterTransaction.get(record.id);

    const updated = this._updateRaw(oldRecord, record);

    this.adapterTransaction.update(updated); // Don't return deleted records -- pretend they are gone

    if (oldRecord && oldRecord._status == "deleted") {
      oldRecord = undefined;
    }

    if (oldRecord) {
      this._queueEvent("update", {
        data: updated,
        oldRecord
      });
    } else {
      this._queueEvent("create", {
        data: updated
      });
    }

    return {
      data: updated,
      oldRecord,
      permissions: {}
    };
  }

}

exports.CollectionTransaction = CollectionTransaction;

},{"./adapters/IDB":4,"./adapters/base":5,"./utils":7,"uuid":2}],7:[function(require,module,exports){
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.sortObjects = sortObjects;
exports.filterObject = filterObject;
exports.filterObjects = filterObjects;
exports.waterfall = waterfall;
exports.deepEqual = deepEqual;
exports.omitKeys = omitKeys;
exports.arrayEqual = arrayEqual;
exports.transformSubObjectFilters = transformSubObjectFilters;
exports.RE_RECORD_ID = void 0;
const RE_RECORD_ID = /^[a-zA-Z0-9][a-zA-Z0-9_-]*$/;
/**
 * Checks if a value is undefined.
 * @param  {Any}  value
 * @return {Boolean}
 */

exports.RE_RECORD_ID = RE_RECORD_ID;

function _isUndefined(value) {
  return typeof value === "undefined";
}
/**
 * Sorts records in a list according to a given ordering.
 *
 * @param  {String} order The ordering, eg. `-last_modified`.
 * @param  {Array}  list  The collection to order.
 * @return {Array}
 */


function sortObjects(order, list) {
  const hasDash = order[0] === "-";
  const field = hasDash ? order.slice(1) : order;
  const direction = hasDash ? -1 : 1;
  return list.slice().sort((a, b) => {
    if (a[field] && _isUndefined(b[field])) {
      return direction;
    }

    if (b[field] && _isUndefined(a[field])) {
      return -direction;
    }

    if (_isUndefined(a[field]) && _isUndefined(b[field])) {
      return 0;
    }

    return a[field] > b[field] ? direction : -direction;
  });
}
/**
 * Test if a single object matches all given filters.
 *
 * @param  {Object} filters  The filters object.
 * @param  {Object} entry    The object to filter.
 * @return {Boolean}
 */


function filterObject(filters, entry) {
  return Object.keys(filters).every(filter => {
    const value = filters[filter];

    if (Array.isArray(value)) {
      return value.some(candidate => candidate === entry[filter]);
    } else if (typeof value === "object") {
      return filterObject(value, entry[filter]);
    } else if (!Object.prototype.hasOwnProperty.call(entry, filter)) {
      console.error(`The property ${filter} does not exist`);
      return false;
    }

    return entry[filter] === value;
  });
}
/**
 * Filters records in a list matching all given filters.
 *
 * @param  {Object} filters  The filters object.
 * @param  {Array}  list     The collection to filter.
 * @return {Array}
 */


function filterObjects(filters, list) {
  return list.filter(entry => {
    return filterObject(filters, entry);
  });
}
/**
 * Resolves a list of functions sequentially, which can be sync or async; in
 * case of async, functions must return a promise.
 *
 * @param  {Array} fns  The list of functions.
 * @param  {Any}   init The initial value.
 * @return {Promise}
 */


function waterfall(fns, init) {
  if (!fns.length) {
    return Promise.resolve(init);
  }

  return fns.reduce((promise, nextFn) => {
    return promise.then(nextFn);
  }, Promise.resolve(init));
}
/**
 * Simple deep object comparison function. This only supports comparison of
 * serializable JavaScript objects.
 *
 * @param  {Object} a The source object.
 * @param  {Object} b The compared object.
 * @return {Boolean}
 */


function deepEqual(a, b) {
  if (a === b) {
    return true;
  }

  if (typeof a !== typeof b) {
    return false;
  }

  if (!(a && typeof a == "object") || !(b && typeof b == "object")) {
    return false;
  }

  if (Object.keys(a).length !== Object.keys(b).length) {
    return false;
  }

  for (const k in a) {
    if (!deepEqual(a[k], b[k])) {
      return false;
    }
  }

  return true;
}
/**
 * Return an object without the specified keys.
 *
 * @param  {Object} obj        The original object.
 * @param  {Array}  keys       The list of keys to exclude.
 * @return {Object}            A copy without the specified keys.
 */


function omitKeys(obj, keys = []) {
  const result = { ...obj
  };

  for (const key of keys) {
    delete result[key];
  }

  return result;
}

function arrayEqual(a, b) {
  if (a.length !== b.length) {
    return false;
  }

  for (let i = a.length; i--;) {
    if (a[i] !== b[i]) {
      return false;
    }
  }

  return true;
}

function makeNestedObjectFromArr(arr, val, nestedFiltersObj) {
  const last = arr.length - 1;
  return arr.reduce((acc, cv, i) => {
    if (i === last) {
      return acc[cv] = val;
    } else if (Object.prototype.hasOwnProperty.call(acc, cv)) {
      return acc[cv];
    } else {
      return acc[cv] = {};
    }
  }, nestedFiltersObj);
}

function transformSubObjectFilters(filtersObj) {
  const transformedFilters = {};

  for (const key in filtersObj) {
    const keysArr = key.split(".");
    const val = filtersObj[key];
    makeNestedObjectFromArr(keysArr, val, transformedFilters);
  }

  return transformedFilters;
}

},{}]},{},[1])(1)
});