postal.js/spec/Postal.spec.js

describe( "Postal", function () {
	var subscription,
		sub,
		channel,
		caughtSubscribeEvent = false,
		caughtUnsubscribeEvent = false;

	describe( "When creating basic subscription", function () {
		var systemSubscription = {};
		before( function () {
			systemSubscription = postal.subscribe( {
				channel : "postal",
				topic : "subscription.created",
				callback : function ( data, envelope ) {
					if ( data.event &&
					     data.event == "subscription.created" &&
					     data.channel == "MyChannel" &&
					     data.topic == "MyTopic" ) {
						caughtSubscribeEvent = true;
					}
				}
			} );
			subscription = postal.channel( "MyChannel" ).subscribe( "MyTopic" , function () {} );
			sub = postal.configuration.bus.subscriptions.MyChannel.MyTopic[0];
		} );
		after( function () {
			systemSubscription.unsubscribe();
			postal.utils.reset();
		} );
		it( "should create a channel called MyChannel", function () {
			expect( postal.configuration.bus.subscriptions["MyChannel"] !== undefined ).to.be.ok();
		} );
		it( "should create a topic under MyChannel called MyTopic", function () {
			expect( postal.configuration.bus.subscriptions["MyChannel"]["MyTopic"] !== undefined ).to.be.ok();
		} );
		it( "should have set subscription channel value", function () {
			expect( sub.channel ).to.be( "MyChannel" );
		} );
		it( "should have set subscription topic value", function () {
			expect( sub.topic ).to.be( "MyTopic" );
		} );
		it( "should have defaulted the subscription constraints array", function () {
			expect( sub.constraints.length ).to.be( 0 );
		} );
		it( "should have defaulted the subscription context value", function () {
			expect( sub.context ).to.be(null);
		} );
		it( "should have captured subscription creation event", function () {
			expect( caughtSubscribeEvent ).to.be.ok();
		} );
	} );
	describe( "When unsubscribing", function () {
		describe( "With a single subscription", function(){
			var subExistsBefore = false,
				subExistsAfter = true;
			var systemSubscription = {};
			before( function () {
				systemSubscription = postal.subscribe( {
					channel : "postal",
					topic : "subscription.*",
					callback : function ( data, env ) {
						if ( data.event &&
						     data.event == "subscription.removed" &&
						     data.channel == "MyChannel" &&
						     data.topic == "MyTopic" ) {
							caughtUnsubscribeEvent = true;
						}
					}
				} );
				subscription = postal.channel( "MyChannel" ).subscribe( "MyTopic" , function () {} );
				subExistsBefore = postal.configuration.bus.subscriptions.MyChannel.MyTopic[0] !== undefined;
				subscription.unsubscribe();
				subExistsAfter = postal.configuration.bus.subscriptions.MyChannel.MyTopic.length !== 0;
			} );
			after( function () {
				systemSubscription.unsubscribe();
				postal.utils.reset();
			} );
			it( "subscription should exist before unsubscribe", function () {
				expect( subExistsBefore ).to.be.ok();
			} );
			it( "subscription should not exist after unsubscribe", function () {
				expect( subExistsAfter ).to.not.be.ok()
			} );
			it( "should have captured unsubscription creation event", function () {
				expect( caughtUnsubscribeEvent ).to.be.ok();
			} );
		});
		describe( "With multiple subscribers on one channel", function() {
			var subscription1, subscription2, results = [];
			before( function () {
				channel = postal.channel();
				subscription1 = channel.subscribe('test', function() {
					results.push('1 received message');
				}).once();

				subscription2 = channel.subscribe('test', function() {
					results.push('2 received message');
				});
				channel.publish('test');
				channel.publish('test');

			});
			after( function () {
				subscription2.unsubscribe();
				postal.utils.reset();
			});
			it( "should produce expected messages", function() {
				expect( results.length ).to.be(3);
				expect( results[0] ).to.be("1 received message");
				expect( results[1] ).to.be("2 received message");
				expect( results[2] ).to.be("2 received message");
			});
		});
	} );
	describe( "When publishing a message", function () {
		var msgReceivedCnt = 0,
			msgData;
		before( function () {
			channel = postal.channel( "MyChannel" );
			subscription = channel.subscribe( "MyTopic", function ( data ) {
				msgReceivedCnt++;
				msgData = data;
			} );
			channel.publish( "MyTopic", "Testing123" );
			subscription.unsubscribe();
			channel.publish( "MyTopic", "Testing123" );
		} );
		after( function () {
			postal.utils.reset();
		} );
		it( "subscription callback should be invoked once", function () {
			expect( msgReceivedCnt ).to.be( 1 );
		} );
		it( "subscription callback should receive published data", function () {
			expect( msgData ).to.be( "Testing123" );
		} );
	} );
	describe( "When subscribing with a disposeAfter of 5", function () {
		var msgReceivedCnt = 0;
		before( function () {
			channel = postal.channel( "MyChannel" );
			subscription = channel.subscribe( "MyTopic", function ( data ) {
				msgReceivedCnt++;
			} )
				.disposeAfter( 5 );
			channel.publish( "MyTopic", "Testing123" );
			channel.publish( "MyTopic", "Testing123" );
			channel.publish( "MyTopic", "Testing123" );
			channel.publish( "MyTopic", "Testing123" );
			channel.publish( "MyTopic", "Testing123" );
			channel.publish( "MyTopic", "Testing123" );
		} );
		after( function () {
			postal.utils.reset();
		} );
		it( "subscription callback should be invoked 5 times", function () {
			expect( msgReceivedCnt ).to.be( 5 );
		} );
	} );
	describe( "When subscribing with once()", function () {
		var msgReceivedCnt = 0;
		before( function () {
			channel = postal.channel( "MyChannel" );
			subscription = channel.subscribe( "MyTopic",function ( data ) {
				msgReceivedCnt++;
			} ).once();
			channel.publish( "MyTopic", "Testing123" );
			channel.publish( "MyTopic", "Testing123" );
			channel.publish( "MyTopic", "Testing123" );
			channel.publish( "MyTopic", "Testing123" );
			channel.publish( "MyTopic", "Testing123" );
			channel.publish( "MyTopic", "Testing123" );
		} );
		after( function () {
			postal.utils.reset();
		} );
		it( "subscription callback should be invoked 1 time", function () {
			expect( msgReceivedCnt ).to.be( 1 );
		} );
	} );
	describe( "When subscribing and ignoring duplicates", function () {
		var subInvokedCnt = 0;
		before( function () {
			channel = postal.channel( "MyChannel" );
			subscription = channel.subscribe( "MyTopic", function ( data ) {
				subInvokedCnt++;
			} )
				.distinctUntilChanged();
			channel.publish( "MyTopic", "Testing123" );
			channel.publish( "MyTopic", "Testing123" );
			channel.publish( "MyTopic", "Testing123" );
			channel.publish( "MyTopic", "Testing123" );
			channel.publish( "MyTopic", "Testing123" );
			channel.publish( "MyTopic", "Testing123" );
		} );
		after( function () {
			postal.utils.reset();
			subInvokedCnt = 0;
		} );
		it( "should have a constraint on the subscription", function () {
			expect( postal.configuration.bus.subscriptions.MyChannel.MyTopic[0].constraints.length ).to.be( 1 );
		} );
		it( "subscription callback should be invoked once", function () {
			expect( subInvokedCnt ).to.be( 1 );
		} );
	} );
	describe( "When subscribing with one constraint returning true", function () {
		var recvd = false;
		before( function () {
			channel = postal.channel( "MyChannel" );
			subscription = channel.subscribe( "MyTopic", function ( data ) {
				recvd = true;
			} )
				.withConstraint( function () {
					return true;
				} );
			channel.publish( "MyTopic", "Testing123" );
		} );
		after( function () {
			postal.utils.reset();
			recvd = false;
		} );
		it( "should have a constraint on the subscription", function () {
			expect( postal.configuration.bus.subscriptions.MyChannel.MyTopic[0].constraints.length ).to.be( 1 );
		} );
		it( "should have invoked the subscription callback", function () {
			expect( recvd ).to.be.ok();
		} );
	} );
	describe( "When subscribing with one constraint returning false", function () {
		var recvd = false;
		before( function () {
			channel = postal.channel( "MyChannel" );
			subscription = channel.subscribe( "MyTopic", function ( data ) {
				recvd = true;
			} )
				.withConstraint( function () {
					return false;
				} );
			channel.publish( "MyTopic", "Testing123" );
		} );
		after( function () {
			postal.utils.reset();
			recvd = false;
		} );
		it( "should have a constraint on the subscription", function () {
			expect( postal.configuration.bus.subscriptions.MyChannel.MyTopic[0].constraints.length ).to.be( 1 );
		} );
		it( "should not have invoked the subscription callback", function () {
			expect( recvd ).to.not.be.ok()
		} );
	} );
	describe( "When subscribing with multiple constraints returning true", function () {
		var recvd = false;
		before( function () {
			channel = postal.channel( "MyChannel" );
			subscription = channel.subscribe( "MyTopic", function ( data ) {
				recvd = true;
			} )
				.withConstraints( [function () {
				return true;
			},
			                       function () {
				                       return true;
			                       },
			                       function () {
				                       return true;
			                       }] );
			channel.publish( "MyTopic", "Testing123" );
		} );
		after( function () {
			postal.utils.reset();
			recvd = false;
		} );
		it( "should have a constraint on the subscription", function () {
			expect( postal.configuration.bus.subscriptions.MyChannel.MyTopic[0].constraints.length ).to.be( 3 );
		} );
		it( "should have invoked the callback", function () {
			expect( recvd ).to.be.ok();
		} );
	} );
	describe( "When subscribing with multiple constraints and one returning false", function () {
		var recvd = false;
		before( function () {
			channel = postal.channel( "MyChannel" );
			subscription = channel.subscribe( "MyTopic", function ( data ) {
				recvd = true;
			} )
				.withConstraints( [function () {
				return true;
			},
			                       function () {
				                       return false;
			                       },
			                       function () {
				                       return true;
			                       }] );
			channel.publish( "MyTopic", "Testing123" );
		} );
		after( function () {
			postal.utils.reset();
			recvd = false;
		} );
		it( "should have a constraint on the subscription", function () {
			expect( postal.configuration.bus.subscriptions.MyChannel.MyTopic[0].constraints.length ).to.be( 3 );
		} );
		it( "should not have invoked the callback", function () {
			expect( recvd ).to.not.be.ok()
		} );
	} );
	describe( "When subscribing with the context being set", function () {
		var count = 0,
			obj = {
				increment : function () {
					count++;
				}
			};
		before( function () {
			channel = postal.channel( "MyChannel" );
			subscription = channel.subscribe( "MyTopic", function ( data ) {
				this.increment();
			} )
				.withContext( obj );
			channel.publish( "MyTopic", "Testing123" );
		} );
		after( function () {
			postal.utils.reset();
		} );
		it( "should have called obj.increment", function () {
			expect( count ).to.be( 1 );
		} );
	} );
	describe( "When subscribing with defer", function () {
		var results = [];
		before( function () {
			channel = postal.channel( "MyChannel" );

		} );
		after( function () {
			postal.utils.reset();
		} );
		it( "should have met expected results", function (done) {
			subscription = channel.subscribe( "MyTopic",
				function ( data ) {
					results.push( "second" );
					expect( results[0] ).to.be( "first" );
					expect( results[1] ).to.be( "second" );
					done();
				} ).defer();
			channel.publish( "MyTopic", "Testing123" );
			results.push( "first" );
		} );
	} );
	describe( "When subscribing with delay", function () {
		var results = [];
		before( function () {
			channel = postal.channel( "MyChannel" );
		} );
		after( function () {
			postal.utils.reset();
		} );
		it( "should have met expected results", function (done) {
			subscription = channel.subscribe("MyTopic",
				function ( data ) {
					results.push( "second" );
					expect( results[0] ).to.be( "first" );
					expect( results[1] ).to.be( "second" );
					done();
				} ).withDelay( 500 );
			channel.publish( "MyTopic", "Testing123" );
			results.push( "first" );
		} );
	} );
	describe( "When subscribing with debounce", function () {
		var results = [], debouncedChannel;
		before( function () {
			debouncedChannel = postal.channel( "MyChannel" );
			subscription = debouncedChannel.subscribe( "MyTopic",
				function ( data ) {
					results.push( data );
				} ).withDebounce( 800 );
		} );
		after( function () {
			postal.utils.reset();
		} );
		it( "should have only invoked debounced callback once", function (done) {
			debouncedChannel.publish( "MyTopic", 1 ); // starts the two second clock on debounce
			setTimeout( function () {
				debouncedChannel.publish( "MyTopic", 2 );
			}, 20 ); // should not invoke callback
			setTimeout( function () {
				debouncedChannel.publish( "MyTopic", 3 );
			}, 80 ); // should not invoke callback
			setTimeout( function () {
				debouncedChannel.publish( "MyTopic", 4 );
			}, 250 ); // should not invoke callback
			setTimeout( function () {
				debouncedChannel.publish( "MyTopic", 5 );
			}, 500 ); // should not invoke callback
			setTimeout( function () {
				debouncedChannel.publish( "MyTopic", 6 );
			}, 1000 ); // should invoke callback
			setTimeout( function () {
				expect( results[0] ).to.be( 6 );
				expect( results.length ).to.be( 1 );
				done();
			}, 2400 );
		} );
	} );
	describe( "When subscribing with throttle", function () {
		var results = [], throttledChannel;
		before( function () {
			throttledChannel = postal.channel( "MyChannel" );
			subscription = throttledChannel.subscribe( "MyTopic",
				function ( data ) {
					results.push( data );
				} ).withThrottle( 500 );
		} );
		after( function () {
			postal.utils.reset();
		} );
		it( "should have only invoked throttled callback twice", function (done) {
			throttledChannel.publish( "MyTopic", 1 ); // starts the two second clock on debounce
			setTimeout( function () {
				throttledChannel.publish( "MyTopic", 800 );
			}, 800 ); // should invoke callback
			for ( var i = 0; i < 20; i++ ) {
				(function ( x ) {
					throttledChannel.publish( "MyTopic", x );
				})( i );
			}
			setTimeout( function () {
				expect( results[0] ).to.be( 1 );
				expect( results[1] ).to.be( 800 );
				expect( results.length ).to.be( 2 );
				done();
			}, 1500 );
		} );
	} );
	describe( "When subscribing with a hierarchical binding, no wildcards", function () {
		var count = 0, channelB, channelC;
		before( function () {
			channel = postal.channel( "MyChannel" );
			subscription = channel.subscribe( "MyTopic.MiddleTopic", function ( data ) {
				count++;
			} );
			channel.publish( "MyTopic.MiddleTopic.SubTopic", "Testing123" );
			channel.publish( "MyTopic.MiddleTopic", "Testing123" );
			channel.publish( "MyTopic.MiddleTopic.SubTopic.YetAnother", "Testing123" );
		} );
		after( function () {
			postal.utils.reset();
			count = 0;
		} );
		it( "should have invoked subscription callback only once", function () {
			expect( count ).to.be( 1 );
		} );
	} );
	describe( "When subscribing with a hierarchical binding, using #", function () {
		var count, channelB, channelC, channelD, channelE;
		before( function () {
    count = 0;
			channel = postal.channel( "MyChannel" );
			subscription = channel.subscribe( "MyTopic.#.SubTopic", function ( data, env ) {
				count++;
			} );
			channel.publish( "MyTopic.MiddleTopic.SubTopic", "Testing123" );
			channel.publish( "MyTopic.MiddleTopic", "Testing123" );
			channel.publish( "MyTopic.MiddleTopic.SubMiddle.SubTopic", "Testing123" );
			channel.publish( "MyTopic.MiddleTopic.SubTopic.YetAnother", "Testing123" );
		} );
		after( function () {
			postal.utils.reset();
			count = 0;
		} );
		it( "should have invoked subscription callback twice", function () {
			expect( count ).to.be( 2 );
		} );
	} );
	describe( "When subscribing with a hierarchical binding, using *", function () {
		var count = 0, channelB, channelC, channelD;
		before( function () {
			channel = postal.channel( "MyChannel" );
			subscription = channel.subscribe( "MyTopic.MiddleTopic.*", function ( data ) {
				count++;
			} );

			channel.publish( "MyTopic.MiddleTopic", "Testing123" );
			channel.publish( "MyTopic.MiddleTopic.SubTopic", "Testing123" );
			channel.publish( "MyTopic.MiddleTopic.SubTopic.YetAnother", "Testing123" );
		} );
		after( function () {
			postal.utils.reset();
			count = 0;
		} );
		it( "should have invoked subscription callback twice", function () {
			expect( count ).to.be( 1 );
		} );
	} );
	describe( "When subscribing with a hierarchical binding, using # and *", function () {
		var count = 0, channelB, channelC, channelD, channelE;
		before( function () {
			channel = postal.channel( "MyChannel" );
			subscription = channel.subscribe( "MyTopic.#.*", function ( data ) {
				count++;
			} );

			channel.publish( "MyTopic.MiddleTopic.SubTopic", "Testing123" );
			channel.publish( "MyTopic.MiddleTopic", "Testing123" );
			channel.publish( "MyTopic.MiddleTopic.SubTopic.YetAnother", "Testing123" );
			channel.publish( "OtherTopic.MiddleTopic.SubTopic.YetAnother", "Testing123" );
		} );
		after( function () {
			postal.utils.reset();
			count = 0;
		} );
		it( "should have invoked subscription callback twice", function () {
			expect( count ).to.be( 3 );
		} );
	} );
	describe( "When using global publish api", function () {
		var msgReceivedCnt = 0,
			msgData;
		before( function () {
			channel = postal.channel( "MyGlobalChannel" );
			subscription = channel.subscribe( "MyTopic", function ( data ) {
				msgReceivedCnt++;
				msgData = data;
			} );
			postal.publish( { channel: "MyGlobalChannel", topic: "MyTopic", data: "Testing123" } );
			subscription.unsubscribe();
			postal.publish( { channel: "MyGlobalChannel", topic: "MyTopic", data: "Testing123" } );
		} );
		after( function () {
			postal.utils.reset();
			msgReceivedCnt = 0;
		} );
		it( "channel should be of type ChannelDefinition", function () {
			expect( channel instanceof ChannelDefinition ).to.be.ok();
		} );
		it( "subscription callback should be invoked once", function () {
			expect( msgReceivedCnt ).to.be( 1 );
		} );
		it( "subscription callback should receive published data", function () {
			expect( msgData ).to.be( "Testing123" );
		} );
	} );
	describe( "When using global subscribe api", function () {
		before( function () {
			subscription = postal.subscribe( {
				channel : "MyChannel",
				topic : "MyTopic",
				callback : function () {
				}
			} );
			sub = postal.configuration.bus.subscriptions.MyChannel.MyTopic[0];
		} );
		after( function () {
			postal.utils.reset();
		} );
		it( "subscription should be of type SubscriptionDefinition", function () {
			expect( subscription instanceof SubscriptionDefinition ).to.be.ok();
		} );
		it( "should create an channel called MyChannel", function () {
			expect( postal.configuration.bus.subscriptions["MyChannel"] !== undefined ).to.be.ok();
		} );
		it( "should create a topic under MyChannel called MyTopic", function () {
			expect( postal.configuration.bus.subscriptions["MyChannel"]["MyTopic"] !== undefined ).to.be.ok();
		} );
		it( "should have set subscription channel value", function () {
			expect( sub.channel ).to.be( "MyChannel" );
		} );
		it( "should have set subscription topic value", function () {
			expect( sub.topic ).to.be( "MyTopic" );
		} );
		it( "should have defaulted the subscription constraints array", function () {
			expect( sub.constraints.length ).to.be( 0 );
		} );
		it( "should have defaulted the subscription context value", function () {
			expect( sub.context ).to.be(null);
		} );
	} );
	describe( "When using global channel api", function () {
		var gch;
		describe( "With no channel name provided", function () {
			describe( "Using string argument", function () {
				before( function () {
					gch = postal.channel( "SomeChannel" );
				} );
				after( function () {
					gch = undefined;
				} );
				it( "channel should be of type ChannelDefinition", function () {
					expect( gch instanceof ChannelDefinition ).to.be.ok();
				} );
				it( "should set channel name to SomeChannel", function () {
					expect( gch.channel ).to.be( "SomeChannel" );
				} );
			} );
		} );
	} );
	describe( "When subscribing and unsubscribing a wire tap", function () {
		var wireTapData,
			wireTapEnvelope,
			wiretap;
		before( function () {
			caughtUnsubscribeEvent = false;
			wireTapData = [];
			wireTapEnvelope = [];
			wiretap = postal.addWireTap( function ( msg, envelope ) {
				wireTapData.push( msg );
				wireTapEnvelope.push( envelope );
			} );
			postal.publish( { topic : "Oh.Hai.There", data : "I'm in yer bus, tappin' yer subscriptionz..."} );
			wiretap();
			postal.publish( { topic : "Oh.Hai.There", data : "I'm in yer bus, tappin' yer subscriptionz..."} );
		} );
		after( function () {
			postal.utils.reset();
		} );
		it( "wire tap should have been invoked only once", function () {
			expect( wireTapData.length ).to.be( 1 );
			expect( wireTapEnvelope.length ).to.be( 1 );
		} );
		it( "wireTap data should match expected results", function () {
			expect( wireTapData[0] ).to.be( "I'm in yer bus, tappin' yer subscriptionz..." );
		} );
		it( "wireTap envelope should match expected results", function () {
			expect( wireTapEnvelope[0].channel ).to.be( DEFAULT_CHANNEL );
			expect( wireTapEnvelope[0].topic ).to.be( "Oh.Hai.There" );
		} );
	} );
	describe( "When calling postal.utils.reset", function () {
		var resolver;
		before( function () {
			postal.utils.reset();
			subscription = postal.channel( "MyChannel" ).subscribe( "MyTopic", function () {
			} );
			postal.channel( "MyChannel" ).publish( "MyTopic", "Oh Hai!" );
			sub = postal.configuration.bus.subscriptions.MyChannel.MyTopic[0];
			resolver = postal.configuration.resolver.cache["MyTopic"];
			postal.utils.reset();
		} );
		after( function () {
		} );
		it( "should have created a subscription definition", function () {
			expect( sub.channel ).to.be( "MyChannel" );
			expect( sub.topic ).to.be( "MyTopic" );
			expect( sub.constraints.length ).to.be( 0 );
			expect( sub.context ).to.be(null);
		} );
		it( "should have created a resolver cache entry", function () {
			expect( _.isEmpty( resolver ) ).to.not.be.ok()
			expect( resolver["MyTopic"] ).to.be.ok();
		} );
		it( "subscriptions cache should now be empty", function () {
			expect( _.isEmpty( postal.configuration.bus.subscriptions ) ).to.be.ok();
		} );
		it( "resolver cache should now be empty", function () {
			expect( _.isEmpty( postal.configuration.resolver.cache ) ).to.be.ok();
		} );
	} );
	describe( "When calling utils.getSubscribersFor", function () {
		var subs = [], i;
		before( function () {
			i = 10;
			var ch1 = postal.channel( "MyChannel" ),
				  ch2 = postal.channel( "MyChannel2" );
			while ( i ) {
				subs.push( ch1.subscribe( "MyTopic", function () {
				} ) );
				subs.push( ch2.subscribe( "MyTopic2", function () {
				} ) );
				i--;
			}
		} );
		after( function () {
			sub = [];
			postal.utils.reset();
		} );
		it( "should return expected results for MyChannel/MyTopic", function () {
			var results = postal.utils.getSubscribersFor( { channel : "MyChannel", topic : "MyTopic" } );
			expect( results.length ).to.be( 10 );
		} );
		it( "should return expected results for MyChannel2/MyTopic2", function () {
			var results = postal.utils.getSubscribersFor( { channel : "MyChannel2", topic : "MyTopic2" } );
			expect( results.length ).to.be( 10 );
		} );
	} );
	describe( "When publishing on a channel where no subscribers exist", function () {
		it( "should return expected results for MyChannel/MyTopic", function () {
			var env = postal.publish({
				channel: "NoOneIsUsingThisOne",
				topic: "This.Is.A.Lonely.Topic",
				data: "Y U NO SUBSCRIBE TO ME?"
			});
			expect( !_.isEmpty(env) ).to.be( true );
		} );
	} );
} );