Event Broken Concept

pkg/eventbroker/broker_test.go

@@ -0,0 +1,524 @@
+package eventbroker
+
+import (
+	"context"
+	"errors"
+	"sync"
+	"sync/atomic"
+	"testing"
+	"time"
+)
+
+func TestNewBroker(t *testing.T) {
+	provider := NewMemoryProvider(MemoryProviderOptions{
+		InstanceID: "test-instance",
+		MaxEvents:  1000,
+	})
+
+	tests := []struct {
+		name      string
+		opts      Options
+		wantError bool
+	}{
+		{
+			name: "valid options",
+			opts: Options{
+				Provider:   provider,
+				InstanceID: "test-instance",
+				Mode:       ProcessingModeSync,
+			},
+			wantError: false,
+		},
+		{
+			name: "missing provider",
+			opts: Options{
+				InstanceID: "test-instance",
+			},
+			wantError: true,
+		},
+		{
+			name: "missing instance ID",
+			opts: Options{
+				Provider: provider,
+			},
+			wantError: true,
+		},
+		{
+			name: "async mode with defaults",
+			opts: Options{
+				Provider:   provider,
+				InstanceID: "test-instance",
+				Mode:       ProcessingModeAsync,
+			},
+			wantError: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			broker, err := NewBroker(tt.opts)
+			if (err != nil) != tt.wantError {
+				t.Errorf("NewBroker() error = %v, wantError %v", err, tt.wantError)
+			}
+			if err == nil && broker == nil {
+				t.Error("Expected non-nil broker")
+			}
+		})
+	}
+}
+
+func TestBrokerStartStop(t *testing.T) {
+	provider := NewMemoryProvider(MemoryProviderOptions{
+		InstanceID: "test-instance",
+	})
+
+	broker, err := NewBroker(Options{
+		Provider:   provider,
+		InstanceID: "test-instance",
+		Mode:       ProcessingModeSync,
+	})
+	if err != nil {
+		t.Fatalf("Failed to create broker: %v", err)
+	}
+
+	// Test Start
+	if err := broker.Start(context.Background()); err != nil {
+		t.Fatalf("Failed to start broker: %v", err)
+	}
+
+	// Test double start (should fail)
+	if err := broker.Start(context.Background()); err == nil {
+		t.Error("Expected error on double start")
+	}
+
+	// Test Stop
+	if err := broker.Stop(context.Background()); err != nil {
+		t.Fatalf("Failed to stop broker: %v", err)
+	}
+
+	// Test double stop (should not fail)
+	if err := broker.Stop(context.Background()); err != nil {
+		t.Error("Double stop should not fail")
+	}
+}
+
+func TestBrokerPublishSync(t *testing.T) {
+	provider := NewMemoryProvider(MemoryProviderOptions{
+		InstanceID: "test-instance",
+	})
+
+	broker, _ := NewBroker(Options{
+		Provider:   provider,
+		InstanceID: "test-instance",
+		Mode:       ProcessingModeSync,
+	})
+	broker.Start(context.Background())
+	defer broker.Stop(context.Background())
+
+	// Subscribe to events
+	called := false
+	var receivedEvent *Event
+	broker.Subscribe("test.*", EventHandlerFunc(func(ctx context.Context, event *Event) error {
+		called = true
+		receivedEvent = event
+		return nil
+	}))
+
+	// Publish event
+	event := NewEvent(EventSourceSystem, "test.event")
+	event.InstanceID = "test-instance"
+	err := broker.PublishSync(context.Background(), event)
+	if err != nil {
+		t.Fatalf("PublishSync failed: %v", err)
+	}
+
+	// Verify handler was called
+	if !called {
+		t.Error("Expected handler to be called")
+	}
+	if receivedEvent == nil || receivedEvent.ID != event.ID {
+		t.Error("Expected to receive the published event")
+	}
+
+	// Verify event status
+	if event.Status != EventStatusCompleted {
+		t.Errorf("Expected status %s, got %s", EventStatusCompleted, event.Status)
+	}
+}
+
+func TestBrokerPublishAsync(t *testing.T) {
+	provider := NewMemoryProvider(MemoryProviderOptions{
+		InstanceID: "test-instance",
+	})
+
+	broker, _ := NewBroker(Options{
+		Provider:    provider,
+		InstanceID:  "test-instance",
+		Mode:        ProcessingModeAsync,
+		WorkerCount: 2,
+		BufferSize:  10,
+	})
+	broker.Start(context.Background())
+	defer broker.Stop(context.Background())
+
+	// Subscribe to events
+	var callCount atomic.Int32
+	broker.Subscribe("test.*", EventHandlerFunc(func(ctx context.Context, event *Event) error {
+		callCount.Add(1)
+		return nil
+	}))
+
+	// Publish multiple events
+	for i := 0; i < 5; i++ {
+		event := NewEvent(EventSourceSystem, "test.event")
+	event.InstanceID = "test-instance"
+		if err := broker.PublishAsync(context.Background(), event); err != nil {
+			t.Fatalf("PublishAsync failed: %v", err)
+		}
+	}
+
+	// Wait for events to be processed
+	time.Sleep(100 * time.Millisecond)
+
+	if callCount.Load() != 5 {
+		t.Errorf("Expected 5 handler calls, got %d", callCount.Load())
+	}
+}
+
+func TestBrokerPublishBeforeStart(t *testing.T) {
+	provider := NewMemoryProvider(MemoryProviderOptions{
+		InstanceID: "test-instance",
+	})
+
+	broker, _ := NewBroker(Options{
+		Provider:   provider,
+		InstanceID: "test-instance",
+	})
+
+	event := NewEvent(EventSourceSystem, "test.event")
+	event.InstanceID = "test-instance"
+	err := broker.Publish(context.Background(), event)
+	if err == nil {
+		t.Error("Expected error when publishing before start")
+	}
+}
+
+func TestBrokerHandlerError(t *testing.T) {
+	provider := NewMemoryProvider(MemoryProviderOptions{
+		InstanceID: "test-instance",
+	})
+
+	broker, _ := NewBroker(Options{
+		Provider:   provider,
+		InstanceID: "test-instance",
+		Mode:       ProcessingModeSync,
+		RetryPolicy: &RetryPolicy{
+			MaxRetries:    2,
+			InitialDelay:  10 * time.Millisecond,
+			MaxDelay:      100 * time.Millisecond,
+			BackoffFactor: 2.0,
+		},
+	})
+	broker.Start(context.Background())
+	defer broker.Stop(context.Background())
+
+	// Subscribe with failing handler
+	var callCount atomic.Int32
+	broker.Subscribe("test.*", EventHandlerFunc(func(ctx context.Context, event *Event) error {
+		callCount.Add(1)
+		return errors.New("handler error")
+	}))
+
+	// Publish event
+	event := NewEvent(EventSourceSystem, "test.event")
+	event.InstanceID = "test-instance"
+	err := broker.PublishSync(context.Background(), event)
+
+	// Should fail after retries
+	if err == nil {
+		t.Error("Expected error from handler")
+	}
+
+	// Should have been called MaxRetries+1 times (initial + retries)
+	if callCount.Load() != 3 {
+		t.Errorf("Expected 3 calls (1 initial + 2 retries), got %d", callCount.Load())
+	}
+
+	// Event should be marked as failed
+	if event.Status != EventStatusFailed {
+		t.Errorf("Expected status %s, got %s", EventStatusFailed, event.Status)
+	}
+}
+
+func TestBrokerMultipleHandlers(t *testing.T) {
+	provider := NewMemoryProvider(MemoryProviderOptions{
+		InstanceID: "test-instance",
+	})
+
+	broker, _ := NewBroker(Options{
+		Provider:   provider,
+		InstanceID: "test-instance",
+		Mode:       ProcessingModeSync,
+	})
+	broker.Start(context.Background())
+	defer broker.Stop(context.Background())
+
+	// Subscribe multiple handlers
+	var called1, called2, called3 bool
+	broker.Subscribe("test.*", EventHandlerFunc(func(ctx context.Context, event *Event) error {
+		called1 = true
+		return nil
+	}))
+	broker.Subscribe("test.event", EventHandlerFunc(func(ctx context.Context, event *Event) error {
+		called2 = true
+		return nil
+	}))
+	broker.Subscribe("*", EventHandlerFunc(func(ctx context.Context, event *Event) error {
+		called3 = true
+		return nil
+	}))
+
+	// Publish event
+	event := NewEvent(EventSourceSystem, "test.event")
+	event.InstanceID = "test-instance"
+	broker.PublishSync(context.Background(), event)
+
+	// All handlers should be called
+	if !called1 || !called2 || !called3 {
+		t.Error("Expected all handlers to be called")
+	}
+}
+
+func TestBrokerUnsubscribe(t *testing.T) {
+	provider := NewMemoryProvider(MemoryProviderOptions{
+		InstanceID: "test-instance",
+	})
+
+	broker, _ := NewBroker(Options{
+		Provider:   provider,
+		InstanceID: "test-instance",
+		Mode:       ProcessingModeSync,
+	})
+	broker.Start(context.Background())
+	defer broker.Stop(context.Background())
+
+	// Subscribe
+	called := false
+	id, _ := broker.Subscribe("test.*", EventHandlerFunc(func(ctx context.Context, event *Event) error {
+		called = true
+		return nil
+	}))
+
+	// Unsubscribe
+	if err := broker.Unsubscribe(id); err != nil {
+		t.Fatalf("Unsubscribe failed: %v", err)
+	}
+
+	// Publish event
+	event := NewEvent(EventSourceSystem, "test.event")
+	event.InstanceID = "test-instance"
+	broker.PublishSync(context.Background(), event)
+
+	// Handler should not be called
+	if called {
+		t.Error("Expected handler not to be called after unsubscribe")
+	}
+}
+
+func TestBrokerStats(t *testing.T) {
+	provider := NewMemoryProvider(MemoryProviderOptions{
+		InstanceID: "test-instance",
+	})
+
+	broker, _ := NewBroker(Options{
+		Provider:   provider,
+		InstanceID: "test-instance",
+		Mode:       ProcessingModeSync,
+	})
+	broker.Start(context.Background())
+	defer broker.Stop(context.Background())
+
+	// Subscribe
+	broker.Subscribe("test.*", EventHandlerFunc(func(ctx context.Context, event *Event) error {
+		return nil
+	}))
+
+	// Publish events
+	for i := 0; i < 3; i++ {
+		event := NewEvent(EventSourceSystem, "test.event")
+	event.InstanceID = "test-instance"
+		broker.PublishSync(context.Background(), event)
+	}
+
+	// Get stats
+	stats, err := broker.Stats(context.Background())
+	if err != nil {
+		t.Fatalf("Stats failed: %v", err)
+	}
+
+	if stats.InstanceID != "test-instance" {
+		t.Errorf("Expected instance ID 'test-instance', got %s", stats.InstanceID)
+	}
+	if stats.TotalPublished != 3 {
+		t.Errorf("Expected 3 published events, got %d", stats.TotalPublished)
+	}
+	if stats.TotalProcessed != 3 {
+		t.Errorf("Expected 3 processed events, got %d", stats.TotalProcessed)
+	}
+	if stats.ActiveSubscribers != 1 {
+		t.Errorf("Expected 1 active subscriber, got %d", stats.ActiveSubscribers)
+	}
+}
+
+func TestBrokerInstanceID(t *testing.T) {
+	provider := NewMemoryProvider(MemoryProviderOptions{
+		InstanceID: "test-instance",
+	})
+
+	broker, _ := NewBroker(Options{
+		Provider:   provider,
+		InstanceID: "my-instance",
+	})
+
+	if broker.InstanceID() != "my-instance" {
+		t.Errorf("Expected instance ID 'my-instance', got %s", broker.InstanceID())
+	}
+}
+
+func TestBrokerConcurrentPublish(t *testing.T) {
+	provider := NewMemoryProvider(MemoryProviderOptions{
+		InstanceID: "test-instance",
+	})
+
+	broker, _ := NewBroker(Options{
+		Provider:    provider,
+		InstanceID:  "test-instance",
+		Mode:        ProcessingModeAsync,
+		WorkerCount: 5,
+		BufferSize:  100,
+	})
+	broker.Start(context.Background())
+	defer broker.Stop(context.Background())
+
+	var callCount atomic.Int32
+	broker.Subscribe("test.*", EventHandlerFunc(func(ctx context.Context, event *Event) error {
+		callCount.Add(1)
+		return nil
+	}))
+
+	// Publish concurrently
+	var wg sync.WaitGroup
+	for i := 0; i < 50; i++ {
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			event := NewEvent(EventSourceSystem, "test.event")
+	event.InstanceID = "test-instance"
+			broker.PublishAsync(context.Background(), event)
+		}()
+	}
+
+	wg.Wait()
+	time.Sleep(200 * time.Millisecond) // Wait for async processing
+
+	if callCount.Load() != 50 {
+		t.Errorf("Expected 50 handler calls, got %d", callCount.Load())
+	}
+}
+
+func TestBrokerGracefulShutdown(t *testing.T) {
+	provider := NewMemoryProvider(MemoryProviderOptions{
+		InstanceID: "test-instance",
+	})
+
+	broker, _ := NewBroker(Options{
+		Provider:    provider,
+		InstanceID:  "test-instance",
+		Mode:        ProcessingModeAsync,
+		WorkerCount: 2,
+		BufferSize:  10,
+	})
+	broker.Start(context.Background())
+
+	var processedCount atomic.Int32
+	broker.Subscribe("test.*", EventHandlerFunc(func(ctx context.Context, event *Event) error {
+		time.Sleep(50 * time.Millisecond) // Simulate work
+		processedCount.Add(1)
+		return nil
+	}))
+
+	// Publish events
+	for i := 0; i < 5; i++ {
+		event := NewEvent(EventSourceSystem, "test.event")
+	event.InstanceID = "test-instance"
+		broker.PublishAsync(context.Background(), event)
+	}
+
+	// Stop broker (should wait for events to be processed)
+	if err := broker.Stop(context.Background()); err != nil {
+		t.Fatalf("Stop failed: %v", err)
+	}
+
+	// All events should be processed
+	if processedCount.Load() != 5 {
+		t.Errorf("Expected 5 processed events, got %d", processedCount.Load())
+	}
+}
+
+func TestBrokerDefaultRetryPolicy(t *testing.T) {
+	policy := DefaultRetryPolicy()
+
+	if policy.MaxRetries != 3 {
+		t.Errorf("Expected MaxRetries 3, got %d", policy.MaxRetries)
+	}
+	if policy.InitialDelay != 1*time.Second {
+		t.Errorf("Expected InitialDelay 1s, got %v", policy.InitialDelay)
+	}
+	if policy.BackoffFactor != 2.0 {
+		t.Errorf("Expected BackoffFactor 2.0, got %f", policy.BackoffFactor)
+	}
+}
+
+func TestBrokerProcessingModes(t *testing.T) {
+	provider := NewMemoryProvider(MemoryProviderOptions{
+		InstanceID: "test-instance",
+	})
+
+	tests := []struct {
+		name string
+		mode ProcessingMode
+	}{
+		{"sync mode", ProcessingModeSync},
+		{"async mode", ProcessingModeAsync},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			broker, _ := NewBroker(Options{
+				Provider:   provider,
+				InstanceID: "test-instance",
+				Mode:       tt.mode,
+			})
+			broker.Start(context.Background())
+			defer broker.Stop(context.Background())
+
+			called := false
+			broker.Subscribe("test.*", EventHandlerFunc(func(ctx context.Context, event *Event) error {
+				called = true
+				return nil
+			}))
+
+			event := NewEvent(EventSourceSystem, "test.event")
+	event.InstanceID = "test-instance"
+			broker.Publish(context.Background(), event)
+
+			if tt.mode == ProcessingModeAsync {
+				time.Sleep(50 * time.Millisecond)
+			}
+
+			if !called {
+				t.Error("Expected handler to be called")
+			}
+		})
+	}
+}