fix(server): keep the Host-header check when binding to all interfaces

Binding HOST=0.0.0.0 no longer sets Vite's allowedHosts to true. The dev and
preview servers accept IP addresses, localhost and the LAN hostnames listed
in GEV_ALLOWED_HOSTS; suffix and wildcard entries are ignored. The
configuration factory takes the resolved list as an input, so build/vite.js
still reads no environment.

Ported from #97 to the current build/vite.js layout. Fixes #21.

Co-authored-by: Sameh Khamis <[email protected]>
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>

build/allowedHosts.js

@@ -0,0 +1,26 @@
+/**
+ * Host header allowlist for the Vite dev/preview server. The configuration
+ * factory passes the configured names in; this module reads no environment.
+ *
+ * Binding to a wildcard interface only controls which network interfaces accept
+ * connections. It must not turn into a wildcard Host-header policy: this server
+ * brokers configured API keys through local proxy routes.
+ */
+export const DEFAULT_ALLOWED_HOSTS = Object.freeze(['localhost', '127.0.0.1']);
+
+/**
+ * Resolve Vite's allowedHosts setting from an optional comma-separated list.
+ * Empty entries and suffix/wildcard entries are ignored; repeated names keep
+ * their first occurrence. Vite treats leading-dot values as suffix wildcards,
+ * which would defeat an explicit host policy.
+ *
+ * @param {string|undefined|null} configuredHosts
+ * @returns {string[]}
+ */
+export function resolveAllowedHosts(configuredHosts) {
+  const hosts = String(configuredHosts ?? '')
+    .split(',')
+    .map((host) => host.trim())
+    .filter((host) => host && !host.startsWith('.') && !host.includes('*'));
+  return [...new Set([...DEFAULT_ALLOWED_HOSTS, ...hosts])];
+}

build/vite.js

@@ -1,5 +1,6 @@
 import { applicationHtmlPlugin } from './application-html.js';
 import cesium from 'vite-plugin-cesium';
+import { DEFAULT_ALLOWED_HOSTS } from './allowedHosts.js';
 import { embedFramingPlugin } from './embed-framing.js';
 import { panelBuildPlugin } from './panel.js';
 
@@ -45,6 +46,7 @@ export function createBrowserViteConfig({
   cesiumToken,
   host = 'localhost',
   port = 4173,
+  allowedHosts = DEFAULT_ALLOWED_HOSTS,
   command,
 } = {}) {
   return {
@@ -73,10 +75,10 @@ export function createBrowserViteConfig({
     server: {
       host: host || 'localhost',
       port: parseInt(port, 10) || 4173,
-      allowedHosts:
-        host === '0.0.0.0' || host === '::'
-          ? true
-          : ['localhost', '127.0.0.1', '.local'],
+      // A wildcard bind only chooses interfaces; it never disables Vite's
+      // Host-header check. LAN hostnames are added explicitly (see
+      // build/allowedHosts.js); IP addresses are always accepted.
+      allowedHosts: [...allowedHosts],
       fs: {
         deny: ['.env', '.env.*', '*.{crt,pem}', '**/.git/**', '**/ENVIRONMENT'],
       },