akkoma/lib/pleroma/web/plugs/frontend_static.ex

115 lines
3.0 KiB
Elixir

# Pleroma: A lightweight social networking server
# Copyright © 2017-2021 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Pleroma.Web.Plugs.FrontendStatic do
require Pleroma.Constants
@frontend_cookie_name "preferred_frontend"
@moduledoc """
This is a shim to call `Plug.Static` but with runtime `from` configuration`. It dispatches to the different frontends.
"""
@behaviour Plug
defp instance_static_path do
Pleroma.Config.get([:instance, :static_dir], "instance/static")
end
def file_path(path, frontend_type \\ :primary)
def file_path(path, frontend_type) when is_atom(frontend_type) do
if configuration = Pleroma.Config.get([:frontends, frontend_type]) do
Path.join([
instance_static_path(),
"frontends",
configuration["name"],
configuration["ref"],
path
])
else
nil
end
end
def file_path(path, frontend_type) when is_binary(frontend_type) do
Path.join([
instance_static_path(),
"frontends",
frontend_type,
path
])
end
def init(opts) do
opts
|> Keyword.put(:from, "__unconfigured_frontend_static_plug")
|> Plug.Static.init()
|> Map.put(:frontend_type, opts[:frontend_type])
|> Map.put(:if, Keyword.get(opts, :if, true))
end
def call(conn, opts) do
with false <- api_route?(conn.path_info),
false <- invalid_path?(conn.path_info),
true <- enabled?(opts[:if]),
fallback_frontend_type <- Map.get(opts, :frontend_type, :primary),
frontend_type <- preferred_or_fallback(conn, fallback_frontend_type),
path when not is_nil(path) <- file_path("", frontend_type) do
call_static(conn, opts, path)
else
_ ->
conn
end
end
def preferred_frontend(conn) do
%{req_cookies: cookies} =
conn
|> Plug.Conn.fetch_cookies()
Map.get(cookies, @frontend_cookie_name)
end
# Only override primary frontend
def preferred_or_fallback(conn, :primary) do
case preferred_frontend(conn) do
nil ->
:primary
frontend ->
if Enum.member?(Pleroma.Config.get([:frontends, :pickable], []), frontend) do
frontend
else
:primary
end
end
end
def preferred_or_fallback(_conn, fallback), do: fallback
defp enabled?(if_opt) when is_function(if_opt), do: if_opt.()
defp enabled?(true), do: true
defp enabled?(_), do: false
defp invalid_path?(list) do
invalid_path?(list, :binary.compile_pattern(["/", "\\", ":", "\0"]))
end
defp invalid_path?([h | _], _match) when h in [".", "..", ""], do: true
defp invalid_path?([h | t], match), do: String.contains?(h, match) or invalid_path?(t)
defp invalid_path?([], _match), do: false
defp api_route?([]), do: false
defp api_route?([h | t]) do
api_routes = Pleroma.Web.Router.get_api_routes()
if h in api_routes, do: true, else: api_route?(t)
end
defp call_static(conn, opts, from) do
opts = Map.put(opts, :from, from)
Plug.Static.call(conn, opts)
end
end