Promise Module

app.js

var express = require('express'),
    app = express(),
    port = process.env.PORT || 3030,
    myModule = require('./myModule')
;

app.get('/', function(request, response, next) {
    myModule("Hello World").done(function(result) {
        response.json(result);
    }).fail(function(error) {
        response.status(400).json(error);
    });
});

app.listen(port, function(){
  console.log('Listening on port ' + port);
});

module.exports = app;

myModule.js

var Deferred = require('simply-deferred').Deferred; // works like jQuerys Deferreds/Promises

module.exports = function(options) {
    var _deffered = new Deferred();

    if (!options) {
        options = {
            text: "It Works"
        };
    }

    setTimeout(function() {
        try {
            var thisString = options.text || options;
            if (typeof thisString == "string") {
                _deffered.resolve(thisString);
            } else {
                _deffered.reject(new Error("value is not a string"));
            }
        } catch (error) {
            _deffered.reject(error);
        }
    }, getRandomInt(50,800));


    return _deffered.promise();
}

function getRandomInt(min, max) {
  return Math.floor(Math.random() * (max - min)) + min;
}

test.js

var request = require('supertest'),
    app = require('./app'),
    myModule = require('./myModule'),
    defaultString = "It Works",
    testString = "This is my Test String"
;

describe("the Server", function() {
    it("starts", function(done) {
        request(app)
            .get("/")
            .expect(200)
            .end(done)
        ;
    });
});

describe("middleware", function() {
    it("returns the default string", function(next) {
        myModule().done(function(result) {
            if (result != defaultString) {
                throw new Error("Expected String to Be ["+defaultString+"], Got ["+result+"]");
            }
        }).fail(function(error) {
            throw error;
        }).always(function() {
            next();
        });
    });

    it("returns the test string", function(next) {
        myModule(testString).done(function(result) {
            if (result != testString) {
                throw new Error("Expected String to Be ["+testString+"], Got ["+result+"]");
            }
        }).fail(function(error) {
            throw error;
        }).always(function() {
            next();
        });
    });

    it("returns the test string in dot notation", function(next) {
        myModule({text: testString}).done(function(result) {
            if (result != testString) {
                throw new Error("Expected String to Be ["+testString+"], Got ["+result+"]");
            }
        }).fail(function(error) {
            throw error;
        }).always(function() {
            next();
        });
    });

    it ("errors when an array is passed", function(next) {
        myModule([1,2,3,4,5]).done(function(result) {
            throw new Error("Expect an error");
        }).always(function() {
            next();
        });
    });

    it ("errors when an array is passed in dot notation", function(next) {
        myModule({text: [1,2,3,4,5]}).done(function(result) {
            throw new Error("Expect an error");
        }).always(function() {
            next();
        });
    });
});