refactor: centralize unhandled rejection setup

src/infra/bonjour.ts

@@ -2,6 +2,8 @@ import os from "node:os";
 
 import { logDebug, logWarn } from "../logger.js";
 import { getLogger } from "../logging.js";
+import { ignoreCiaoCancellationRejection } from "./bonjour-ciao.js";
+import { formatBonjourError } from "./bonjour-errors.js";
 import { registerUnhandledRejectionHandler } from "./unhandled-rejections.js";
 
 export type GatewayBonjourAdvertiser = {
@@ -45,14 +47,6 @@ type BonjourService = {
   serviceState: string;
 };
 
-function formatBonjourError(err: unknown): string {
-  if (err instanceof Error) {
-    const msg = err.message || String(err);
-    return err.name && err.name !== "Error" ? `${err.name}: ${msg}` : msg;
-  }
-  return String(err);
-}
-
 function serviceSummary(label: string, svc: BonjourService): string {
   let fqdn = "unknown";
   let hostname = "unknown";
@@ -147,16 +141,7 @@ export async function startGatewayBonjourAdvertiser(
   let ciaoCancellationRejectionHandler: (() => void) | undefined;
   if (services.length > 0) {
     ciaoCancellationRejectionHandler = registerUnhandledRejectionHandler(
-      (reason) => {
-        const message = formatBonjourError(reason).toUpperCase();
-        if (!message.includes("CIAO ANNOUNCEMENT CANCELLED")) {
-          return false;
-        }
-        logDebug(
-          `bonjour: ignoring unhandled ciao rejection: ${formatBonjourError(reason)}`,
-        );
-        return true;
-      },
+      ignoreCiaoCancellationRejection,
     );
   }