domotz-remote-pawn/src/commands/httpScanPorts.js

Domotz Agent

/** This file is part of Domotz Agent.
  * Copyright (C) 2016  Domotz Ltd
  *
  * Domotz Agent is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation, either version 3 of the License, or
  * (at your option) any later version.
  *
  * Domotz Agent is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with Domotz Agent.  If not, see <http://www.gnu.org/licenses/>.
  **/
/**
 * This command performs a simple http port scan: it executes the same HTTP request
 * on different ports of the same host and returns a dictionary, indexed by port, with
 * the results of an httpRequest for each port.
 * @param message the following fields are read:
 *  - host: the host name or ip address
 *  - path: the http resource, the URL part after the port
 *  - method: the http method used (f.e. GET, POST)
 *  - body [optional]: the body of the various http requests
 *  - ports: either an array of integers or a string 'n:m' where n < m
 *
 * @param resourceLocator
 * @returns {{execute: Function, describe: Function}}
 */
var httpScanPorts = function (message, resourceLocator) {
    var payload = message.payload;
    if (typeof payload.ports === 'string') {
        var tmp = payload.ports.split(':');
        payload.ports = [];
        for (var i = tmp[0]; i <= tmp[1]; i++) {
            payload.ports.push(parseInt(i, 10));
        }
    }
    return {
        execute: function (callback) {
            var subCommands = {};

            /**
             * Creates an httpRequest command that perform a request on the
             * n-th port of the list of the server
             * @param n
             * @returns command
             */
            var createHttpRequestCommand = function (n) {
                var httpRequest = resourceLocator.commandHttpRequest;
                var port = payload.ports[n];
                return httpRequest.command({
                    payload: {
                        path: payload.path,
                        host: payload.host,
                        port: port,
                        method: payload.method,
                        headers: payload.headers,
                        body: payload.body
                    },
                    correlationId: message.correlationId + ':' + port
                }, resourceLocator);
            };

            /**
             * Checks whether all the pending httpRequests finished
             * @returns {boolean}
             */
            var allResultsArrived = function () {
                for (var i = 0; i < payload.ports.length; i++) {
                    if (subCommands[payload.ports[i]] === undefined) {
                        console.log("Message not arrived for port: " + payload.ports[i] + ': ' + subCommands[payload.ports[i]]);
                        return false;
                    }
                }
                return true;
            };

            /**
             * Callback that handles the response to the request on the specified port
             * If the current one is the last request to have been arrived, calls the
             * httpScanPorts callback with the final result
             * @param port
             * @returns {Function}
             */
            var processNthResult = function (port) {
                return function (result) {
                    console.log(message.correlationId + " - Response arrived for port: " + port);
                    subCommands[port] = result;
                    if (allResultsArrived()) {
                        console.log(message.correlationId + " - All messages arrived");
                        callback(subCommands);
                    }
                };
            };

            for (var i = 0; i < payload.ports.length; i++) {
                var port = payload.ports[i];
                createHttpRequestCommand(i).execute(processNthResult(port));
            }
        },
        describe: function () {
            return message.correlationId + " - httpScanPorts - " + payload.method + ' - http://' + payload.host +
                ':' + JSON.stringify(payload.ports) + payload.path;
        }
    };
};


module.exports.command = httpScanPorts;