nxkit/mqtt/store.js

This is a collection of tools, independent of any other libraries

"use strict";
/* ***** BEGIN LICENSE BLOCK *****
 * Distributed under the BSD license:
 *
 * Copyright (c) 2015, xuewen.chu
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of xuewen.chu nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL xuewen.chu BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * ***** END LICENSE BLOCK ***** */
Object.defineProperty(exports, "__esModule", { value: true });
const stream_1 = require("stream");
/**
 * Module dependencies
 */
function xtend(...args) {
    return Object.assign({}, ...args);
}
const streamsOpts = { objectMode: true };
const defaultStoreOptions = { clean: true };
class Store {
    /**
     * In-memory implementation of the message store
     * This can actually be saved into files.
     *
     * @param {Object} [options] - store options
     */
    constructor(options) {
        this._inflights = new Map();
        this.options = xtend(defaultStoreOptions, options);
    }
    /**
     * Adds a packet to the store, a packet is
     * anything that has a messageId property.
     *
     */
    put(packet, cb) {
        this._inflights.set(packet.messageId, packet);
        if (cb) {
            cb();
        }
        return this;
    }
    /**
     * Creates a stream with all the packets in the store
     *
     */
    createStream() {
        var stream = new stream_1.Readable(streamsOpts);
        var destroyed = false;
        var values = [];
        var i = 0;
        this._inflights.forEach(function (value, key) {
            values.push(value);
        });
        stream._read = function () {
            if (!destroyed && i < values.length) {
                this.push(values[i++]);
            }
            else {
                this.push(null);
            }
        };
        stream.destroy = function () {
            if (destroyed) {
                return;
            }
            var self = this;
            destroyed = true;
            process.nextTick(function () {
                self.emit('close');
            });
        };
        return stream;
    }
    /**
     * deletes a packet from the store.
     */
    del(packet, cb) {
        packet = this._inflights.get(packet.messageId);
        if (packet) {
            this._inflights.delete(packet.messageId);
            cb(undefined, packet);
        }
        else if (cb) {
            cb(new Error('missing packet'));
        }
        return this;
    }
    /**
     * get a packet from the store.
     */
    get(packet, cb) {
        packet = this._inflights.get(packet.messageId);
        if (packet) {
            cb(undefined, packet);
        }
        else /* if (cb)*/ {
            cb(new Error('missing packet'));
        }
        return this;
    }
    /**
     * Close the store
     */
    close(cb) {
        if (this.options.clean) {
            this._inflights = null;
        }
        if (cb) {
            cb();
        }
    }
}
exports.default = Store;