From abeaff09a811234805d566db38131cf5cbbda94b Mon Sep 17 00:00:00 2001
From: Yeonuk Hwang <charlie.hwang131@gmail.com>
Date: Sat, 9 May 2026 00:20:04 +0930
Subject: [PATCH] fix(pubsub): respect channelBufferSize parameter in Subsribe

`NewBrokerWithOptions` accepted `channelBufferSize` parameter, but never
stored or used it, so `Subsribe`` always used the hardcoded
`bufferSize` constant (64).
---
 internal/pubsub/broker.go | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/internal/pubsub/broker.go b/internal/pubsub/broker.go
index 2faf7f89b7c982950bfc69801a7901526e37eec4..52e827c2d6306fa2365372b9867810d9b99d0227 100644
--- a/internal/pubsub/broker.go
+++ b/internal/pubsub/broker.go
@@ -8,11 +8,12 @@ import (
 const bufferSize = 64
 
 type Broker[T any] struct {
-	subs      map[chan Event[T]]struct{}
-	mu        sync.RWMutex
-	done      chan struct{}
-	subCount  int
-	maxEvents int
+	subs              map[chan Event[T]]struct{}
+	mu                sync.RWMutex
+	done              chan struct{}
+	subCount          int
+	maxEvents         int
+	channelBufferSize int
 }
 
 func NewBroker[T any]() *Broker[T] {
@@ -21,9 +22,10 @@ func NewBroker[T any]() *Broker[T] {
 
 func NewBrokerWithOptions[T any](channelBufferSize, maxEvents int) *Broker[T] {
 	return &Broker[T]{
-		subs:      make(map[chan Event[T]]struct{}),
-		done:      make(chan struct{}),
-		maxEvents: maxEvents,
+		subs:              make(map[chan Event[T]]struct{}),
+		done:              make(chan struct{}),
+		maxEvents:         maxEvents,
+		channelBufferSize: channelBufferSize,
 	}
 }
 
@@ -58,7 +60,7 @@ func (b *Broker[T]) Subscribe(ctx context.Context) <-chan Event[T] {
 	default:
 	}
 
-	sub := make(chan Event[T], bufferSize)
+	sub := make(chan Event[T], b.channelBufferSize)
 	b.subs[sub] = struct{}{}
 	b.subCount++