feat: support enbale nginx debug_connection (#8637)

internal/ingress/controller/config/config.go

@@ -768,6 +768,11 @@ type Configuration struct {
 	// GlobalRateLimitStatucCode determines the HTTP status code to return
 	// when limit is exceeding during global rate limiting.
 	GlobalRateLimitStatucCode int `json:"global-rate-limit-status-code"`
+
+	// DebugConnections Enables debugging log for selected client connections
+	// http://nginx.org/en/docs/ngx_core_module.html#debug_connection
+	// Default: ""
+	DebugConnections []string `json:"debug-connections"`
 }
 
 // NewDefault returns the default nginx configuration
@@ -932,6 +937,7 @@ func NewDefault() Configuration {
 		GlobalRateLimitMemcachedMaxIdleTimeout: 10000,
 		GlobalRateLimitMemcachedPoolSize:       50,
 		GlobalRateLimitStatucCode:              429,
+		DebugConnections:                       []string{},
 	}
 
 	if klog.V(5).Enabled() {