Use finch everywhere (#33)

[akkoma] / lib / pleroma / web / media_proxy / media_proxy_controller.ex

diff --git a/lib/pleroma/web/media_proxy/media_proxy_controller.ex b/lib/pleroma/web/media_proxy/media_proxy_controller.ex
index ff7fd240977cc853603f089e14779f18054a6608..b3a92d75a9b157b0f33f11ad27ae90f6400fdbc8 100644 (file)
--- a/lib/pleroma/web/media_proxy/media_proxy_controller.ex
+++ b/lib/pleroma/web/media_proxy/media_proxy_controller.ex
@@ -1,5 +1,5 @@
 # Pleroma: A lightweight social networking server
-# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
+# Copyright © 2017-2021 Pleroma Authors <https://pleroma.social/>
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.MediaProxy.MediaProxyController do
@@ -7,6 +7,7 @@ defmodule Pleroma.Web.MediaProxy.MediaProxyController do
 
   alias Pleroma.Config
   alias Pleroma.Helpers.MediaHelper
+  alias Pleroma.Helpers.UriHelper
   alias Pleroma.ReverseProxy
   alias Pleroma.Web.MediaProxy
   alias Plug.Conn
@@ -34,7 +35,8 @@ defmodule Pleroma.Web.MediaProxy.MediaProxyController do
 
   def preview(%Conn{} = conn, %{"sig" => sig64, "url" => url64}) do
     with {_, true} <- {:enabled, MediaProxy.preview_enabled?()},
-         {:ok, url} <- MediaProxy.decode_url(sig64, url64) do
+         {:ok, url} <- MediaProxy.decode_url(sig64, url64),
+         :ok <- MediaProxy.verify_request_path_and_url(conn, url) do
       handle_preview(conn, url)
     else
       {:enabled, false} ->
@@ -52,10 +54,31 @@ defmodule Pleroma.Web.MediaProxy.MediaProxyController do
     media_proxy_url = MediaProxy.url(url)
 
     with {:ok, %{status: status} = head_response} when status in 200..299 <-
-           Pleroma.HTTP.request("head", media_proxy_url, [], [], pool: :media) do
+           Pleroma.HTTP.request("head", media_proxy_url, [], [], name: MyFinch) do
       content_type = Tesla.get_header(head_response, "content-type")
-      handle_preview(content_type, conn, media_proxy_url)
+      content_length = Tesla.get_header(head_response, "content-length")
+      content_length = content_length && String.to_integer(content_length)
+      static = conn.params["static"] in ["true", true]
+
+      cond do
+        static and content_type == "image/gif" ->
+          handle_jpeg_preview(conn, media_proxy_url)
+
+        static ->
+          drop_static_param_and_redirect(conn)
+
+        content_type == "image/gif" ->
+          redirect(conn, external: media_proxy_url)
+
+        min_content_length_for_preview() > 0 and content_length > 0 and
+            content_length < min_content_length_for_preview() ->
+          redirect(conn, external: media_proxy_url)
+
+        true ->
+          handle_preview(content_type, conn, media_proxy_url)
+      end
     else
+      # If HEAD failed, redirecting to media proxy URI doesn't make much sense; returning an error
       {_, %{status: status}} ->
         send_resp(conn, :failed_dependency, "Can't fetch HTTP headers (HTTP #{status}).")
 
@@ -67,18 +90,6 @@ defmodule Pleroma.Web.MediaProxy.MediaProxyController do
     end
   end
 
-  defp handle_preview(
-         "image/" <> _ = _content_type,
-         %{params: %{"output_format" => "jpeg"}} = conn,
-         media_proxy_url
-       ) do
-    handle_jpeg_preview(conn, media_proxy_url)
-  end
-
-  defp handle_preview("image/gif" = _content_type, conn, media_proxy_url) do
-    redirect(conn, external: media_proxy_url)
-  end
-
   defp handle_preview("image/png" <> _ = _content_type, conn, media_proxy_url) do
     handle_png_preview(conn, media_proxy_url)
   end
@@ -91,15 +102,15 @@ defmodule Pleroma.Web.MediaProxy.MediaProxyController do
     handle_video_preview(conn, media_proxy_url)
   end
 
-  defp handle_preview(content_type, conn, _media_proxy_url) do
-    send_resp(conn, :unprocessable_entity, "Unsupported content type: #{content_type}.")
+  defp handle_preview(_unsupported_content_type, conn, media_proxy_url) do
+    fallback_on_preview_error(conn, media_proxy_url)
   end
 
   defp handle_png_preview(conn, media_proxy_url) do
     quality = Config.get!([:media_preview_proxy, :image_quality])
+    {thumbnail_max_width, thumbnail_max_height} = thumbnail_max_dimensions()
 
-    with {thumbnail_max_width, thumbnail_max_height} <- thumbnail_max_dimensions(),
-         {:ok, thumbnail_binary} <-
+    with {:ok, thumbnail_binary} <-
            MediaHelper.image_resize(
              media_proxy_url,
              %{
@@ -114,15 +125,15 @@ defmodule Pleroma.Web.MediaProxy.MediaProxyController do
       |> send_resp(200, thumbnail_binary)
     else
       _ ->
-        send_resp(conn, :failed_dependency, "Can't handle preview.")
+        fallback_on_preview_error(conn, media_proxy_url)
     end
   end
 
   defp handle_jpeg_preview(conn, media_proxy_url) do
     quality = Config.get!([:media_preview_proxy, :image_quality])
+    {thumbnail_max_width, thumbnail_max_height} = thumbnail_max_dimensions()
 
-    with {thumbnail_max_width, thumbnail_max_height} <- thumbnail_max_dimensions(),
-         {:ok, thumbnail_binary} <-
+    with {:ok, thumbnail_binary} <-
            MediaHelper.image_resize(
              media_proxy_url,
              %{max_width: thumbnail_max_width, max_height: thumbnail_max_height, quality: quality}
@@ -132,7 +143,7 @@ defmodule Pleroma.Web.MediaProxy.MediaProxyController do
       |> send_resp(200, thumbnail_binary)
     else
       _ ->
-        send_resp(conn, :failed_dependency, "Can't handle preview.")
+        fallback_on_preview_error(conn, media_proxy_url)
     end
   end
 
@@ -144,10 +155,23 @@ defmodule Pleroma.Web.MediaProxy.MediaProxyController do
       |> send_resp(200, thumbnail_binary)
     else
       _ ->
-        send_resp(conn, :failed_dependency, "Can't handle preview.")
+        fallback_on_preview_error(conn, media_proxy_url)
     end
   end
 
+  defp drop_static_param_and_redirect(conn) do
+    uri_without_static_param =
+      conn
+      |> current_url()
+      |> UriHelper.modify_uri_params(%{}, ["static"])
+
+    redirect(conn, external: uri_without_static_param)
+  end
+
+  defp fallback_on_preview_error(conn, media_proxy_url) do
+    redirect(conn, external: media_proxy_url)
+  end
+
   defp put_preview_response_headers(
          conn,
          [content_type, filename] = _content_info \\ ["image/jpeg", "preview.jpg"]
@@ -159,7 +183,7 @@ defmodule Pleroma.Web.MediaProxy.MediaProxyController do
   end
 
   defp thumbnail_max_dimensions do
-    config = Config.get([:media_preview_proxy], [])
+    config = media_preview_proxy_config()
 
     thumbnail_max_width = Keyword.fetch!(config, :thumbnail_max_width)
     thumbnail_max_height = Keyword.fetch!(config, :thumbnail_max_height)
@@ -167,6 +191,14 @@ defmodule Pleroma.Web.MediaProxy.MediaProxyController do
     {thumbnail_max_width, thumbnail_max_height}
   end
 
+  defp min_content_length_for_preview do
+    Keyword.get(media_preview_proxy_config(), :min_content_length, 0)
+  end
+
+  defp media_preview_proxy_config do
+    Config.get!([:media_preview_proxy])
+  end
+
   defp media_proxy_opts do
     Config.get([:media_proxy, :proxy_opts], [])
   end