ribbons.application/lib/application.js

Prototype for Ribbons applications.

var fileSystem = require("fs");
var http = require('http');
var url = require('url');
var path = require('path');
var util = require('util');

var Component = require('ribbons.component');

function Application(options) {
  Component.call(this, options);
  options = options || {};
  this.name = options.name || 'Application';
  this.directory = options.directory;
  this.debug = options.debug;
  this.apiPort = options.apiPort || 1701;
  this.apiHost = options.apiHost || '127.0.0.1';
}
util.inherits(Application, Component);

// TODO: DRY up these loops
Application.prototype.init = function () {
  requireComponents.call(this);
  
  for (controller in this.controllers) {
    this.controllers[controller].sensors = this.sensors;
    this.controllers[controller].actuators = this.actuators;
    this.controllers[controller].init();
  }
  for (sensor in this.sensors) {
    this.sensors[sensor].platforms = this.platforms;
    this.sensors[sensor].debug = this.debug;
    this.sensors[sensor].init();
  }
  for (actuator in this.actuators) {
    this.actuators[actuator].platforms = this.platforms;
    this.actuators[actuator].debug = this.debug;
    this.actuators[actuator].init();
  }
}

Application.prototype.start = function() {
  var self = this;
  
  for (controller in this.controllers) {
    this.controllers[controller].start();
  }
  
  for (sensor in this.sensors) {
    this.sensors[sensor].start();
  }

  for (actuator in this.actuators) {
    this.actuators[actuator].start();
  }
  
  // TODO consider making the API a module.
  http.createServer(function (req, res) {
    var pathParts = url.parse(req.url).pathname.split('/');
    var resource = self[pathParts[1]];
    if (pathParts.length === 3) {
      resource = resource[pathParts[2]];
    }
    res.writeHead(200, {'Content-Type': 'application/json'});
    res.end(JSON.stringify(resource));
  }).listen(this.apiPort, this.apiHost);
  this.info('API running at http://' + this.apiHost + ':' + this.apiPort);
};

Application.prototype.stop = function() {
  for (controller in this.controllers) {
    this.controllers[controller].stop();
  }
  
  for (sensor in this.sensors) {
    this.sensors[sensor].stop();
  }

  for (actuator in this.actuators) {
    this.actuators[actuator].stop();
  }
};

// user app directory names for each base type
Application.baseTypes = {
  'platforms': undefined,
  'actuators': undefined,
  'sensors': undefined,
  'controllers': undefined
};

function requireComponents () {
  var app = this;
  
  this.info('requireComponents','start');
  
  // 'sensors', 'actuators', 'controllers'
  for (baseTypeName in Application.baseTypes) {

    // like: setting up app.actuators
    app[baseTypeName] = {};
    
    // like: file path to ./app/actuators/
    var baseTypePath = this.directory + path.sep + baseTypeName; 

    if (fileSystem.existsSync(baseTypePath)) {

      fileSystem.readdirSync(baseTypePath).forEach(function requireComponent(componentFileName) {

        app.info('requireComponent',baseTypeName, baseTypePath);

        // like: var leds = {led12: new Led(12), led13: new Led(13)}
        var components = require(baseTypePath + path.sep + componentFileName);

        // like: for (led in leds)
        for (componentName in components) {
          // like: app.actuators.led13 = leds[led13]
          app[baseTypeName][componentName] = components[componentName];
          components[componentName].name = componentName;
        }
      });
    } else {
      this.warn(baseTypeName, 'not found', this.directory + path.sep + baseTypeName);
    }
  }
}

module.exports = Application;