dpaw-monorail-plugin/src/netward/monorail.js

JS library to link the brocket network to the QGIS/monorail server

/**
 * @fileOverview
 * @name monorail.js
 * @author Gavin Coombes
 * @license BSD-3-Clause
 *
 * Harvest the QGIS map state from the monorail server
 *
 */

let axios = require('axios');
let events = require('events');


let u = require('dpaw-brocket-utility');

// Local Aliases
var log = u.log;

var HarvestModule = (function(){
  let obj = Object.create(new events.EventEmitter());
  obj.$type = "HarvestModule";
  return obj;
})();

var HarvestObject = Object.create(HarvestModule);

HarvestObject.init = function init(opts){
  let self = this;
  self.opts = opts;
  this.type = 'HarvestObject';
  this._port = opts.port || 30000;
  this.address = opts.address || buildAddress(this._port);
  this.interval = opts.interval || 10 * 1000;
};

HarvestObject.port = function port(value) {
  let self = this;
  if (arguments.length) {
    self._port = value;
    self.address = buildAddress(self._port);
    log('HarvestObject.port: port now ', self._port);
  } else {
    return self._value;
  }
};

HarvestObject.fetch = function fetch(address) {
  let self = this;
  return axios.get(self.address)
    .then(self.notify.bind(self));
};

HarvestObject.command = function command(cmd) {
  let self = this;
  let {tag, payload} = cmd;
  let params = `?${tag}=${payload}`;
  let address = self.address + params;
  log('MonorailObject.command: Command is', cmd);
  log('MonorailObject.command: Address is', address);
  return axios.post(address)
    .then(self.notify.bind(self));
};

HarvestObject.run = function run() {
  this.fetch(this.address)
    .then(setTimeout(this.run.bind(this), this.interval));
};

HarvestObject.notify = function notify(res) {
  let data = res.data;
  this.emit('data', data);
};

function buildAddress(port) {
  return `http://localhost:${port}/api/extent`;
}


module.exports = HarvestObject;