Defer pulibc and uplaod middlewares

Signed-off-by: Alexandre Bodin <bodin.alex@gmail.com>

packages/strapi-plugin-upload/middlewares/upload/index.js

@@ -22,6 +22,6 @@ module.exports = strapi => ({
       strapi.app.onerror(err);
     });
 
-    strapi.router.get('/uploads/(.*)', range, koaStatic(staticDir));
+    strapi.router.get('/uploads/(.*)', range, koaStatic(staticDir, { defer: true }));
   },
 });

packages/strapi/lib/middlewares/public/index.js

@@ -27,21 +27,14 @@ module.exports = strapi => {
       const { defaultIndex, maxAge, path: publicPath } = strapi.config.middleware.settings.public;
       const staticDir = path.resolve(strapi.dir, publicPath || strapi.config.paths.static);
 
-      // Match every route with an extension.
-      // The file without extension will not be served.
-      // Note: This route can be overriden by the user.
-      strapi.router.get(
-        '/(.*)',
-        koaStatic(staticDir, {
-          maxage: maxAge,
-          defer: false,
-        })
-      );
-
       if (defaultIndex === true) {
         const index = fs.readFileSync(path.join(__dirname, 'index.html'), 'utf8');
 
-        const serveIndexPage = async ctx => {
+        const serveIndexPage = async (ctx, next) => {
+          // defer rendering of strapi index page
+          await next();
+          if (ctx.body != null || ctx.status !== 404) return;
+
           ctx.url = 'index.html';
           const isInitialised = await utils.isInitialised(strapi);
           const data = {
@@ -70,6 +63,15 @@ module.exports = strapi => {
         strapi.router.get('/index.html', serveIndexPage);
       }
 
+      // serve files in public folder unless a sub router renders something else
+      strapi.router.get(
+        '/(.*)',
+        koaStatic(staticDir, {
+          maxage: maxAge,
+          defer: true,
+        })
+      );
+
       if (!strapi.config.serveAdminPanel) return;
 
       const basename = _.get(strapi.config.currentEnvironment.server, 'admin.path')