From 468b7e15954df04bff84a99252fc6ced16aa5816 Mon Sep 17 00:00:00 2001
From: RMidhunSuresh <hi@midhun.dev>
Date: Thu, 21 Apr 2022 12:52:42 +0530
Subject: [PATCH] Cache config.json

---
 src/platform/web/Platform.js |  2 +-
 src/platform/web/sw.js       | 35 ++++++++++++++++++++++++++++++++++-
 vite.config.js               |  5 +++++
 3 files changed, 40 insertions(+), 2 deletions(-)

diff --git a/src/platform/web/Platform.js b/src/platform/web/Platform.js
index 92608d75..7d5126dc 100644
--- a/src/platform/web/Platform.js
+++ b/src/platform/web/Platform.js
@@ -171,7 +171,7 @@ export class Platform {
             if (!this._configURL) {
                 throw new Error("Neither config nor configURL was provided!");
             }
-            const {body}= await this.request(this._configURL, {method: "GET", format: "json"}).response();
+            const {body}= await this.request(this._configURL, {method: "GET", format: "json", cache: true}).response();
             this._config = body;
         }
         this._notificationService = new NotificationService(
diff --git a/src/platform/web/sw.js b/src/platform/web/sw.js
index c5f69438..e57634fc 100644
--- a/src/platform/web/sw.js
+++ b/src/platform/web/sw.js
@@ -75,7 +75,14 @@ self.addEventListener('fetch', (event) => {
     This has to do with xhr not being supported in service workers.
     */
     if (event.request.method === "GET") {
-        event.respondWith(handleRequest(event.request));
+        if (event.request.url.includes("config.json")) {
+            /**
+             * Use a different strategy for this file.
+             */
+            event.respondWith(handleConfigRequest(event.request));
+        } else {
+            event.respondWith(handleRequest(event.request));
+        }
     }
 });
 
@@ -119,6 +126,32 @@ async function handleRequest(request) {
     }
 }
 
+async function handleConfigRequest(request) {
+    const url = new URL(request.url);
+    // rewrite / to /index.html so it hits the cache
+    if (url.origin === baseURL.origin && url.pathname === baseURL.pathname) {
+        request = new Request(new URL("index.html", baseURL.href));
+    }
+    let response = await readCache(request);
+    if (response) {
+        fetchAndUpdateConfig(request);
+        return response;
+    }
+    response = await fetchAndUpdateConfig(request);
+    return response;
+}
+
+async function fetchAndUpdateConfig(request) {
+    const response = await fetch(request, {
+        signal: pendingFetchAbortController.signal,
+        headers: {
+            "Cache-Control": "no-cache",
+        },
+    });
+    updateCache(request, response.clone());
+    return response;
+}
+
 async function updateCache(request, response) {
     // don't write error responses to the cache
     if (response.status >= 400) {
diff --git a/vite.config.js b/vite.config.js
index 4dd35af2..87e3d063 100644
--- a/vite.config.js
+++ b/vite.config.js
@@ -14,6 +14,11 @@ export default defineConfig(({mode}) => {
             outDir: "../../../target",
             minify: true,
             sourcemap: true,
+            rollupOptions: {
+                output: {
+                    assetFileNames: (asset) => asset.name.includes("config.json") ? "assets/[name][extname]": "assets/[name].[hash][extname]",
+                },
+            },
         },
         plugins: [
             themeBuilder({