machina

Meteor package for workflow: machina.js Finite State Machine (FSM), client & server

Background:

A Finite State Machine is a computational abstraction that:

• Has a finite number of states in which it can exist
• Can only be in one state at any time
• Accepts input
• Can produce output determined by state &/or input
• Can transition from one state to another

Source: “Taming Complexity In JavaScript With Machina.js” by Jim Cowart

Usage:

The global namespace 'machina' is available in both client & server contexts:

Example Template:

<template name="connection_tpl">
  <div id="connection-div" class="col-sm-12 alert alert-success">
        <div><label>Connection Status:&nbsp;</label>{{connection_status}}</div>
  </div>
</template>

Example View:

Deps.autorun(function () {
  var connected = Meteor.status().connected;
  Session.set("connected", connected);
});

Template.connection_tpl.rendered = function () {
    var Div_Connection = $(this.find("#connection-div"));

    var onlineFsm = new machina.Fsm({
        initialState: "online",
        states : {
            online : {
                   _onEnter: function() {
                        Div_Connection.removeClass('alert-danger').addClass('alert-success');
                    },
            },
            offline : {
                   _onEnter: function() {
                        Div_Connection.removeClass('alert-success').addClass('alert-danger');
                    },
            },
        },
    });
}

Template.connection_tpl.helpers({
	connection_status: function () {
	  return Session.get("connected") ? "On" : "Off";
	}
});

See Also:

Taking control with machina.js