From 0f143fd2502d2833892bb96be93db602c60ea01e Mon Sep 17 00:00:00 2001
From: Jeff Posnick <jeffy@google.com>
Date: Wed, 15 Nov 2017 11:11:15 -0500
Subject: [PATCH] Add a localhost-only log message pointing folks to the PWA
 docs.

---
 .../react-scripts/template/src/registerServiceWorker.js  | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/packages/react-scripts/template/src/registerServiceWorker.js b/packages/react-scripts/template/src/registerServiceWorker.js
index 12542ba2295..a3e6c0cfc10 100644
--- a/packages/react-scripts/template/src/registerServiceWorker.js
+++ b/packages/react-scripts/template/src/registerServiceWorker.js
@@ -35,6 +35,15 @@ export default function register() {
       if (isLocalhost) {
         // This is running on localhost. Lets check if a service worker still exists or not.
         checkValidServiceWorker(swUrl);
+
+        // Add some additional logging to localhost, pointing developers to the
+        // service worker/PWA documentation.
+        navigator.serviceWorker.ready.then(() => {
+          console.log(
+            'This web app is being served cache-first by a service ' +
+              'worker. To learn more, visit https://goo.gl/SC7cgQ'
+          );
+        });
       } else {
         // Is not local host. Just register service worker
         registerValidSW(swUrl);