From 1a7b8991a3e389907fdb6f7b09395245f7ac9a67 Mon Sep 17 00:00:00 2001
From: fiatjaf <fiatjaf@gmail.com>
Date: Thu, 18 Jan 2024 11:49:16 -0300
Subject: [PATCH] pool: deduplicate relay urls list.

---
 pool.go | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/pool.go b/pool.go
index e2825fb..40ccd5f 100644
--- a/pool.go
+++ b/pool.go
@@ -9,6 +9,7 @@ import (
 	"time"
 
 	"github.com/puzpuzpuz/xsync/v3"
+	"golang.org/x/exp/slices"
 )
 
 const (
@@ -107,7 +108,14 @@ func (pool *SimplePool) subMany(ctx context.Context, urls []string, filters Filt
 
 	pending := xsync.NewCounter()
 	pending.Add(int64(len(urls)))
-	for _, url := range urls {
+	for i, url := range urls {
+		url = NormalizeURL(url)
+		urls[i] = url
+		if idx := slices.Index(urls, url); idx != i {
+			// skip duplicate relays in the list
+			continue
+		}
+
 		go func(nm string) {
 			defer func() {
 				pending.Dec()
@@ -202,7 +210,7 @@ func (pool *SimplePool) subMany(ctx context.Context, urls []string, filters Filt
 				time.Sleep(interval)
 				interval = interval * 17 / 10 // the next time we try we will wait longer
 			}
-		}(NormalizeURL(url))
+		}(url)
 	}
 
 	return events