FrontendStatic: Add plug to serve frontends based on configuration.

test/plugs/instance_static_test.exs

@@ -2,7 +2,7 @@
 # Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
 # SPDX-License-Identifier: AGPL-3.0-only
 
-defmodule Pleroma.Web.RuntimeStaticPlugTest do
+defmodule Pleroma.Web.InstanceStaticPlugTest do
   use Pleroma.Web.ConnCase
 
   @dir "test/tmp/instance_static"
@@ -24,6 +24,28 @@ defmodule Pleroma.Web.RuntimeStaticPlugTest do
     assert html_response(index, 200) == "hello world"
   end
 
+  test "also overrides frontend files", %{conn: conn} do
+    name = "pelmora"
+    ref = "uguu"
+
+    clear_config([:frontends, :primary], %{"name" => name, "ref" => ref})
+
+    bundled_index = get(conn, "/")
+    refute html_response(bundled_index, 200) == "from frontend plug"
+
+    path = "#{@dir}/frontends/#{name}/#{ref}"
+    File.mkdir_p!(path)
+    File.write!("#{path}/index.html", "from frontend plug")
+
+    index = get(conn, "/")
+    assert html_response(index, 200) == "from frontend plug"
+
+    File.write!(@dir <> "/index.html", "from instance static")
+
+    index = get(conn, "/")
+    assert html_response(index, 200) == "from instance static"
+  end
+
   test "overrides any file in static/static" do
     bundled_index = get(build_conn(), "/static/terms-of-service.html")