fixup! Add pool management.

pool.go

@@ -236,16 +236,15 @@ func (b *BaseClient) refreshConnectionPool() {
 
 // StopPoolMonitor gracefully stops the pool health monitor
 // Call this when shutting down the application
+// Uses sync.Once to ensure it only executes once, preventing race conditions
 func (b *BaseClient) StopPoolMonitor() {
 	if b.pool_warmup_enabled {
-		b.Logger.Info(&libpack_logger.LogMessage{
-			Message: "Stopping pool monitor",
-			Pairs:   nil,
+		b.pool_stop_once.Do(func() {
+			b.Logger.Info(&libpack_logger.LogMessage{
+				Message: "Stopping pool monitor",
+				Pairs:   nil,
+			})
+			b.pool_stop <- true
 		})
-		select {
-		case b.pool_stop <- true:
-		default:
-			// Channel already has a value or monitor already stopped
-		}
 	}
 }

structs.go

@@ -2,6 +2,7 @@ package gql
 
 import (
 	"net/http"
+	"sync"
 	"time"
 
 	cache "github.com/lukaszraczylo/go-simple-graphql/cache"
@@ -22,6 +23,7 @@ type BaseClient struct {
 	pool_warmup_query    string        // Query to use for warming up connections
 	pool_health_interval time.Duration // Interval for pool health checks
 	pool_stop            chan bool     // Channel to stop pool monitor
+	pool_stop_once       sync.Once     // Ensures StopPoolMonitor is called only once
 	MaxGoRoutines        int
 	cache_global         bool
 	retries_enable       bool