Add subscription event delivery

events/events.go

@@ -58,4 +58,6 @@ const (
 	OnPurchasedPaidMedia = "onPurchasedPaidMedia"
 	// OnManagedBot is emitted when a managed bot update is received.
 	OnManagedBot = "onManagedBot"
+	// OnSubscription is emitted when a bot subscription update is received.
+	OnSubscription = "onSubscription"
 )

events/types.go

@@ -113,3 +113,8 @@ type PurchasedPaidMediaEvent struct {
 type ManagedBotEvent struct {
 	ManagedBot *client.ManagedBotUpdated
 }
+
+// SubscriptionEvent is emitted when a bot subscription update is received.
+type SubscriptionEvent struct {
+	Subscription *client.BotSubscriptionUpdated
+}

handlers/handler.go

@@ -75,3 +75,6 @@ type PurchasedPaidMediaHandler func(ctx context.Context, event *events.Purchased
 
 // ManagedBotHandler is a function that handles a managed bot event.
 type ManagedBotHandler func(ctx context.Context, event *events.ManagedBotEvent) error
+
+// SubscriptionHandler is a function that handles a bot subscription update event.
+type SubscriptionHandler func(ctx context.Context, event *events.SubscriptionEvent) error

handlers/registry.go

@@ -238,6 +238,11 @@ func (r *Registry) OnManagedBot(handler ManagedBotHandler) eventemitter.Unsubscr
 	return onEvent(r, events.OnManagedBot, "OnManagedBot", handler)
 }
 
+// OnSubscription registers a handler for bot subscription update events.
+func (r *Registry) OnSubscription(handler SubscriptionHandler) eventemitter.UnsubscribeFunc {
+	return onEvent(r, events.OnSubscription, "OnSubscription", handler)
+}
+
 func (r *Registry) onMessageEvent(
 	event string,
 	name string,

handlers/registry_test.go

@@ -220,6 +220,37 @@ func TestRegistry(t *testing.T) {
 		}
 	})
 
+	t.Run("OnSubscription", func(t *testing.T) {
+		var called bool
+		var payload *events.SubscriptionEvent
+		unsub := reg.OnSubscription(func(_ context.Context, event *events.SubscriptionEvent) error {
+			called = true
+			payload = event
+
+			return nil
+		})
+
+		expectedPayload := &events.SubscriptionEvent{}
+		ee.Emit(context.Background(), events.OnSubscription, expectedPayload)
+		if !called {
+			t.Fatal("handler was not called")
+		}
+		if payload != expectedPayload {
+			t.Fatalf("payload mismatch: got %p, want %p", payload, expectedPayload)
+		}
+
+		called = false
+		payload = nil
+		unsub()
+		ee.Emit(context.Background(), events.OnSubscription, expectedPayload)
+		if called {
+			t.Fatal("handler was called after unsubscribe")
+		}
+		if payload != nil {
+			t.Fatalf("payload=%v, want nil after unsubscribe", payload)
+		}
+	})
+
 	t.Run("OnCommandName", func(t *testing.T) {
 		var called bool
 		unsub := reg.OnCommandName("start", func(_ context.Context, event *events.CommandEvent) error {

listeners/classifier.go

@@ -66,11 +66,19 @@ func classifyMessages(ctx context.Context, emitter eventemitter.EventEmitter, up
 
 func classifyQueries(ctx context.Context, emitter eventemitter.EventEmitter, update *client.Update) {
 	if update.CallbackQuery != nil {
-		emitter.Emit(ctx, events.OnCallbackQuery, &events.CallbackQueryEvent{CallbackQuery: update.CallbackQuery})
+		emitter.Emit(
+			ctx,
+			events.OnCallbackQuery,
+			&events.CallbackQueryEvent{CallbackQuery: update.CallbackQuery},
+		)
 	}
 
 	if update.InlineQuery != nil {
-		emitter.Emit(ctx, events.OnInlineQuery, &events.InlineQueryEvent{InlineQuery: update.InlineQuery})
+		emitter.Emit(
+			ctx,
+			events.OnInlineQuery,
+			&events.InlineQueryEvent{InlineQuery: update.InlineQuery},
+		)
 	}
 
 	if update.ChosenInlineResult != nil {
@@ -80,7 +88,11 @@ func classifyQueries(ctx context.Context, emitter eventemitter.EventEmitter, upd
 	}
 
 	if update.ShippingQuery != nil {
-		emitter.Emit(ctx, events.OnShippingQuery, &events.ShippingQueryEvent{ShippingQuery: update.ShippingQuery})
+		emitter.Emit(
+			ctx,
+			events.OnShippingQuery,
+			&events.ShippingQueryEvent{ShippingQuery: update.ShippingQuery},
+		)
 	}
 
 	if update.PreCheckoutQuery != nil {
@@ -137,26 +149,42 @@ func classifyChatUpdates(ctx context.Context, emitter eventemitter.EventEmitter,
 }
 
 func classifyBusinessUpdates(ctx context.Context, emitter eventemitter.EventEmitter, update *client.Update) {
-	if update.BusinessConnection != nil {
-		emitter.Emit(ctx, events.OnBusinessConnection, &events.BusinessConnectionEvent{
-			BusinessConnection: update.BusinessConnection,
-		})
-	}
-
-	if update.DeletedBusinessMessages != nil {
-		emitter.Emit(ctx, events.OnDeletedBusinessMessages, &events.DeletedBusinessMessagesEvent{
-			DeletedBusinessMessages: update.DeletedBusinessMessages,
-		})
-	}
-
-	if update.PurchasedPaidMedia != nil {
-		emitter.Emit(ctx, events.OnPurchasedPaidMedia, &events.PurchasedPaidMediaEvent{
-			PurchasedPaidMedia: update.PurchasedPaidMedia,
-		})
-	}
-
-	if update.ManagedBot != nil {
-		emitter.Emit(ctx, events.OnManagedBot, &events.ManagedBotEvent{ManagedBot: update.ManagedBot})
+	for _, candidate := range []struct {
+		event   string
+		payload any
+	}{
+		{
+			event: events.OnBusinessConnection,
+			payload: &events.BusinessConnectionEvent{
+				BusinessConnection: update.BusinessConnection,
+			},
+		},
+		{
+			event: events.OnDeletedBusinessMessages,
+			payload: &events.DeletedBusinessMessagesEvent{
+				DeletedBusinessMessages: update.DeletedBusinessMessages,
+			},
+		},
+		{
+			event: events.OnPurchasedPaidMedia,
+			payload: &events.PurchasedPaidMediaEvent{
+				PurchasedPaidMedia: update.PurchasedPaidMedia,
+			},
+		},
+		{
+			event:   events.OnManagedBot,
+			payload: &events.ManagedBotEvent{ManagedBot: update.ManagedBot},
+		},
+		{
+			event: events.OnSubscription,
+			payload: &events.SubscriptionEvent{
+				Subscription: update.Subscription,
+			},
+		},
+	} {
+		if !isNilPayload(candidate.payload) {
+			emitter.Emit(ctx, candidate.event, candidate.payload)
+		}
 	}
 }
 
@@ -166,3 +194,20 @@ func emitMessage(ctx context.Context, emitter eventemitter.EventEmitter, event s
 		Type:    messagetype.Detect(message),
 	})
 }
+
+func isNilPayload(payload any) bool {
+	switch v := payload.(type) {
+	case *events.BusinessConnectionEvent:
+		return v.BusinessConnection == nil
+	case *events.DeletedBusinessMessagesEvent:
+		return v.DeletedBusinessMessages == nil
+	case *events.PurchasedPaidMediaEvent:
+		return v.PurchasedPaidMedia == nil
+	case *events.ManagedBotEvent:
+		return v.ManagedBot == nil
+	case *events.SubscriptionEvent:
+		return v.Subscription == nil
+	default:
+		return payload == nil
+	}
+}

listeners/classifier_test.go

@@ -237,6 +237,17 @@ func TestClassifier(t *testing.T) {
 					}
 				},
 			},
+			{
+				name:   "Subscription",
+				update: &client.Update{Subscription: &client.BotSubscriptionUpdated{}},
+				event:  events.OnSubscription,
+				assertType: func(t *testing.T, payload any) {
+					t.Helper()
+					if _, ok := payload.(*events.SubscriptionEvent); !ok {
+						t.Fatalf("payload type=%T, want *events.SubscriptionEvent", payload)
+					}
+				},
+			},
 		}
 
 		for _, tt := range tests {