add x-weatherstar header for specific 404 detection

README.md

@@ -87,6 +87,13 @@ Simply bind mount your music folder and the playlist will be created
 automatically. If no files are found in `/music`, the built in tracks located in
 `/music/default/` will be used instead.
 
+The nginx configuration also sets the `X-Weatherstar: true` header on all
+responses. This uses `add_header ... always` so the header is sent even for
+404 responses. When `playlist.json` returns a 404 with this header present, the
+browser falls back to scanning the `/music` directory. If you host the static
+files elsewhere, be sure to include this header so the playlist can be generated
+automatically.
+
 ## What's different
 
 I've made several changes to this Weather Star 4000 simulation compared to the original hardware unit and the code that this was forked from.

nginx.conf

@@ -4,6 +4,8 @@ server {
 
     root /usr/share/nginx/html;
 
+    add_header X-Weatherstar true always;
+
     location / {
         index  redirect.html index.html index.htm;
         try_files $uri $uri/ =404;

server/scripts/modules/media.mjs

@@ -1,4 +1,4 @@
-import { json, text } from './utils/fetch.mjs';
+import { text } from './utils/fetch.mjs';
 import Setting from './utils/setting.mjs';
 
 let playlist;
@@ -42,9 +42,17 @@ const scanMusicDirectory = async () => {
 
 const getMedia = async () => {
         try {
-                // fetch the playlist
-                const rawPlaylist = await json('playlist.json');
-                playlist = rawPlaylist;
+                const response = await fetch('playlist.json');
+                if (response.ok) {
+                        playlist = await response.json();
+                } else if (response.status === 404
+                        && response.headers.get('X-Weatherstar') === 'true') {
+                        console.warn("Couldn't get playlist.json, falling back to directory scan");
+                        playlist = await scanMusicDirectory();
+                } else {
+                        console.warn(`Couldn't get playlist.json: ${response.status} ${response.statusText}`);
+                        playlist = { availableFiles: [] };
+                }
         } catch (e) {
                 console.warn("Couldn't get playlist.json, falling back to directory scan");
                 playlist = await scanMusicDirectory();