bhudgeons/octopusjs

A object composition library

Octopus.js

octopus.js is a object composition library that allows you to create object classes with traits/mixins called tentacles. It is like a build your own class or object from the all-you-can-code functionality bar.

This creates a class definition that has events, a state-machine, has a view itself, holds other views, and is lockable. The construct function will be called when our composite class is initialized after all the trait construct functions have been called.

var BuildYourOwnClass = Octopus.spawn(["events", "stateMachine", "view", "viewContainer", "lockable"], {
	construct:function(locked, elementid) {
		this.state("Idle");
		this.setLocked(locked);
		this.view.setEl($("#"+elementid));
	},
	doSomeThisClassStuff:function() {
		if(!this.isLocked()) {
			// do some things
		}
	}
}
'

var byo = new BuildYourOwnClass(false, "someElementId"); byo.state("Running"); byo.doSomeThisClassStuff();

NOTE: as of now all examples are stub code they will be replaced with examples from the jasmine-tests as they are added.

The _8 identifier is a short form to call Octopus.

 var models = _8.path("myapp.models");
 var EventTimer = _8.spawn(["events, timer"]);

Tentacles/Traits and Object Composition:

Tentacles/Traits are the selections on the build your own functionality. They are traits/mixins that are the building blocks of a Octopus composite object. They are the tentacles of a Octopus. The t function take a String id and a object containing the functions to be grafted onto the composite class's prototype. If a construct function (Optional) is defined it will be called when composite class is initialized before the class construct function is called.

In this example we have a library that can check out books to students, other libraries, so we want to create a borrower trait.

To create a tentacle for the borrowing functionality.

Octopus.t("borrower", {
	construct:function() {
		
		this._checkedOut = [];
	},
	
	// all other functions are placed onto the composite objects prototype
	checkout:function(book) {
		this._checkedOut.push(book);
	}
});


Octopus.t("scheduled", {
	setSchedule:function(schedule) {
		this.schedule = schedule;
	}
})

Create the Student composite class definition. You can pass the tentacle list as a comma delimited string or an array of strings.

var Student = Octopus.spawn("borrower, scheduled, otherStudentTrait", {
	// this will be called after all traits have been initialized 
	construct:function(name, schedule) {
		console.log("create student "+id+" ");
		this.setSchedule(schedule);
		
		// all new students live in redthorn hall no matter what for some reason...
		this.moveIn("redthorn hall");
	},
	// adding student specific functions
	moveIn:function(dorm) {
		this.dorm = dorm;
	}
});

Create a new student.

var myStudent = new Student("jethro", {"biology":"104", "welding":"201"});

Adding Backbone Events as a tentacle.

_8.t("events", Backbone.Events);

var PostOffice = _8.spawn("events, goverment, employer");
var hollowStation = new PostOffice("898739-872");
hollowStation.bind("mail", function() {
	// do some mail reading stuff
});

A simple state-machine tentacle.

_8.t("stateMachine", {
	construct:function() {
		this._states = {};
		this._currentState = null;
	},
	state:function(id, state) {
		if(state) {
			this._createState(id, state.enter, state.exit);
			return;
		}
		if(this._states[id]) {
			if(this._currentState) 
				this._states[this.currentState].exit.call(this)
			this.currentState = id;
			this._states[id].enter.call(this);
		}
	},
	isState:function(state) {
		return this.currentState == state;
	},
	_createState:function(id, enter, exit) {
		if(!enter) enter = function() {};
		if(!exit) exit = function() {};
		this._states[id] = {enter:enter, exit:exit}
	}
});

A color tentacle.

_8.t("color", {
	construct:function() {
		this.setColor("none");
	},
	setColor:function(clr) {
		this.color = clr;
	}
});

A SignalLight composite class with color and stateMachine.

var SignalLight = _8.spawn("stateMachine, color", {
	construct:function(initialState) {
		this.state("on", {enter:function() {
			this.setColor("green");
		}});
		this.state("off", {enter:function() {
			this.setColor("red");
		}});
		this.state(initialState);
	}
});

var corner1 = new SignalLight("off");
signalLight.state("on");

Namespacing:

You can defined create/get/append with Octopus.path. The first argument is the path as a dot-notation String. If the second argument is a object it will be appended to the path.

Octopus.path("myapp.models", {
	_books:[];
	BookModel:function(title, author) {
		this.title = title;
		this.author = author;
	},
	addBook:function(title, author) {
		this._books.push(new this.Bookmodel(title, Author);
	}
});

Somewhere else in your app.

var models = Octopus.path("myapp.models");
models.addBook("Smashed, Squashed, Splattered, Chewed, Chunked and Spewed", "Lance Carbuncle");

Dependency Injection:

Using traits for dependency injection.

var viewManager = new ViewManager();

Octopus.t("viewEnabled", {
	construct:function() {
		this.viewManager = viewManager
	}
	render:function() {
		this.viewManager.addView(this);
	},
	remove:function() {
		this.viewManager.removeView(this);
	}
});

Using Octopus.go takes two arguments. The fist is a object in the format of injectName:injectedPath. The second is the anonymous function we want our paths injected into.

Octopus.go({

	// import a path
	"models":"com.testApp.models",
	
	// import a singleton object
	"view":"com.testApp.viewManager",
	
	// import a single function
	"getTime":"com.testApp.utils.getTime",
	
}, function() {
	  var interaction = new this.models.InteractionModel(this.getTime());
	  this.viewManager.appendInteractionList(interaction);
	
});