+ defp handle_preview("image/png" <> _ = _content_type, conn, media_proxy_url) do
+ handle_png_preview(conn, media_proxy_url)
+ end
+
+ defp handle_preview("image/" <> _ = _content_type, conn, media_proxy_url) do
+ handle_jpeg_preview(conn, media_proxy_url)
+ end
+
+ defp handle_preview("video/" <> _ = _content_type, conn, media_proxy_url) do
+ handle_video_preview(conn, media_proxy_url)
+ end
+
+ 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 {:ok, thumbnail_binary} <-
+ MediaHelper.image_resize(
+ media_proxy_url,
+ %{
+ max_width: thumbnail_max_width,
+ max_height: thumbnail_max_height,
+ quality: quality,
+ format: "png"
+ }
+ ) do
+ conn
+ |> put_preview_response_headers(["image/png", "preview.png"])
+ |> send_resp(200, thumbnail_binary)
+ else
+ _ ->
+ 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 {:ok, thumbnail_binary} <-
+ MediaHelper.image_resize(
+ media_proxy_url,
+ %{max_width: thumbnail_max_width, max_height: thumbnail_max_height, quality: quality}
+ ) do
+ conn
+ |> put_preview_response_headers()
+ |> send_resp(200, thumbnail_binary)
+ else
+ _ ->
+ fallback_on_preview_error(conn, media_proxy_url)
+ end
+ end
+
+ defp handle_video_preview(conn, media_proxy_url) do
+ with {:ok, thumbnail_binary} <-
+ MediaHelper.video_framegrab(media_proxy_url) do
+ conn
+ |> put_preview_response_headers()
+ |> send_resp(200, thumbnail_binary)
+ else
+ _ ->
+ 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"]
+ ) do
+ conn
+ |> put_resp_header("content-type", content_type)
+ |> put_resp_header("content-disposition", "inline; filename=\"#{filename}\"")
+ |> put_resp_header("cache-control", ReverseProxy.default_cache_control_header())
+ end
+
+ defp thumbnail_max_dimensions do
+ config = media_preview_proxy_config()
+
+ thumbnail_max_width = Keyword.fetch!(config, :thumbnail_max_width)
+ thumbnail_max_height = Keyword.fetch!(config, :thumbnail_max_height)
+
+ {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