Harness for comparing and contrasting Class Based API or Callback Function API

configService-callbacks.js

// Config Service using callback
var Service = function(query, readyCallback, errorCallback) {
  var arc = "arc data";
  if(query.indexOf("bad") > -1) {
    if(typeof errorCallback === 'function') {
      errorCallback("bad contents");
    }
  }
  else {
    if(typeof readyCallback === 'function') {
      readyCallback(arc);
    }
  }
}

module.exports = Service;

configService-class.js

// Config Service API using promises?
var Service = function() {
  this.ready = function(callback) { this.readyCallback = callback; return this; };
  this.error = function(callback) { this.errorCallback = callback; return this; };
  this.config = function(query) { handleQuery(query); };

  function handleQuery(query) {
    var arc = "arc data";
    if(query.indexOf("bad") > -1) {
      if(typeof this.errorCallback === 'function') {
        this.errorCallback("bad contents");
      }
    }
    else {
      if(typeof this.readyCallback === 'function') {
        this.readyCallback(arc);
      }
    }
  }

  return this;
}

module.exports = Service;

run.js

// Example A: Service as a factory that can be configured
var serviceFactory = require('./configService-class');
var serviceA = serviceFactory().ready(function(result) {
  console.log("A Result: " + result);
}).error(function(error) {
  console.log("A Error: " + error);
});

serviceA.config("A1 my good query");
serviceA.config("A2 my nice query");
serviceA.config("A3 my bad query");

// Example B: Service as a function with a callback
var serviceB = require('./configService-callbacks');

function handleSucess(result) {
  console.log("B Result: " + result);
}

function handleError(error) {
  console.log("B Error: " + error);
}

serviceB("B1 my good query", handleSucess, handleError);
serviceB("B2 my nice query", handleSucess, handleError);
serviceB("B3 my bad query", handleSucess, handleError);