Refactor websocket model to reduce duplicated code.

websocket/notifier_test.go

@@ -0,0 +1,90 @@
+// Copyright 2014 Team 254. All Rights Reserved.
+// Author: pat@patfairbank.com (Patrick Fairbank)
+
+package websocket
+
+import (
+	"github.com/stretchr/testify/assert"
+	"io/ioutil"
+	"log"
+	"testing"
+)
+
+func TestNotifier(t *testing.T) {
+	notifier := NewNotifier("testMessageType", generateTestMessage)
+
+	// Should do nothing when there are no listeners.
+	notifier.Notify()
+	notifier.NotifyWithMessage(12345)
+	notifier.NotifyWithMessage(struct{}{})
+
+	listener := notifier.listen()
+	notifier.Notify()
+	message := <-listener
+	assert.Equal(t, "testMessageType", message.messageType)
+	assert.Equal(t, "test message", message.messageBody)
+	notifier.NotifyWithMessage(12345)
+	assert.Equal(t, 12345, (<-listener).messageBody)
+
+	// Should allow multiple messages without blocking.
+	notifier.NotifyWithMessage("message1")
+	notifier.NotifyWithMessage("message2")
+	notifier.Notify()
+	assert.Equal(t, "message1", (<-listener).messageBody)
+	assert.Equal(t, "message2", (<-listener).messageBody)
+	assert.Equal(t, "test message", (<-listener).messageBody)
+
+	// Should stop sending messages and not block once the buffer is full.
+	log.SetOutput(ioutil.Discard) // Silence noisy log output.
+	for i := 0; i < 20; i++ {
+		notifier.NotifyWithMessage(i)
+	}
+	var value messageEnvelope
+	var lastValue interface{}
+	for lastValue == nil {
+		select {
+		case value = <-listener:
+		default:
+			lastValue = value.messageBody
+			return
+		}
+	}
+	notifier.NotifyWithMessage("next message")
+	assert.True(t, lastValue.(int) < 10)
+	assert.Equal(t, "next message", (<-listener).messageBody)
+}
+
+func TestNotifyMultipleListeners(t *testing.T) {
+	notifier := NewNotifier("testMessageType2", nil)
+	listeners := [50]chan messageEnvelope{}
+	for i := 0; i < len(listeners); i++ {
+		listeners[i] = notifier.listen()
+	}
+
+	notifier.Notify()
+	notifier.NotifyWithMessage(12345)
+	for listener := range notifier.listeners {
+		assert.Equal(t, nil, (<-listener).messageBody)
+		assert.Equal(t, 12345, (<-listener).messageBody)
+	}
+
+	// Should reap closed channels automatically.
+	close(listeners[4])
+	notifier.NotifyWithMessage("message1")
+	assert.Equal(t, 49, len(notifier.listeners))
+	for listener := range notifier.listeners {
+		assert.Equal(t, "message1", (<-listener).messageBody)
+	}
+	close(listeners[16])
+	close(listeners[21])
+	close(listeners[49])
+	notifier.NotifyWithMessage("message2")
+	assert.Equal(t, 46, len(notifier.listeners))
+	for listener := range notifier.listeners {
+		assert.Equal(t, "message2", (<-listener).messageBody)
+	}
+}
+
+func generateTestMessage() interface{} {
+	return "test message"
+}