akkoma/lib/pleroma/web/media_proxy/media_proxy_controller.ex
2020-05-14 20:18:31 +03:00

149 lines
5.2 KiB
Elixir

# Pleroma: A lightweight social networking server
# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Pleroma.Web.MediaProxy.MediaProxyController do
use Pleroma.Web, :controller
alias Pleroma.Config
alias Pleroma.Helpers.MogrifyHelper
alias Pleroma.ReverseProxy
alias Pleroma.Web.MediaProxy
def remote(conn, %{"sig" => sig64, "url" => url64}) do
with {_, true} <- {:enabled, MediaProxy.enabled?()},
{:ok, url} <- MediaProxy.decode_url(sig64, url64),
:ok <- MediaProxy.verify_request_path_and_url(conn, url) do
proxy_opts = Config.get([:media_proxy, :proxy_opts], [])
ReverseProxy.call(conn, url, proxy_opts)
else
{:enabled, false} ->
send_resp(conn, 404, Plug.Conn.Status.reason_phrase(404))
{:error, :invalid_signature} ->
send_resp(conn, 403, Plug.Conn.Status.reason_phrase(403))
{:wrong_filename, filename} ->
redirect(conn, external: MediaProxy.build_url(sig64, url64, filename))
end
end
def preview(conn, %{"sig" => sig64, "url" => url64}) do
with {_, true} <- {:enabled, MediaProxy.preview_enabled?()},
{:ok, url} <- MediaProxy.decode_url(sig64, url64),
:ok <- MediaProxy.verify_request_path_and_url(conn, url) do
handle_preview(conn, url)
else
{:enabled, false} ->
send_resp(conn, 404, Plug.Conn.Status.reason_phrase(404))
{:error, :invalid_signature} ->
send_resp(conn, 403, Plug.Conn.Status.reason_phrase(403))
{:wrong_filename, filename} ->
redirect(conn, external: MediaProxy.build_preview_url(sig64, url64, filename))
end
end
defp handle_preview(conn, url) do
with {:ok, %{status: status} = head_response} when status in 200..299 <-
Tesla.head(url, opts: [adapter: [timeout: preview_head_request_timeout()]]) do
content_type = Tesla.get_header(head_response, "content-type")
handle_preview(content_type, conn, url)
else
{_, %{status: status}} ->
send_resp(conn, :failed_dependency, "Can't fetch HTTP headers (HTTP #{status}).")
{:error, :recv_response_timeout} ->
send_resp(conn, :failed_dependency, "HEAD request timeout.")
_ ->
send_resp(conn, :failed_dependency, "Can't fetch HTTP headers.")
end
end
defp thumbnail_max_dimensions(params) do
config = Config.get([:media_preview_proxy], [])
thumbnail_max_width =
if w = params["thumbnail_max_width"] do
String.to_integer(w)
else
Keyword.fetch!(config, :thumbnail_max_width)
end
thumbnail_max_height =
if h = params["thumbnail_max_height"] do
String.to_integer(h)
else
Keyword.fetch!(config, :thumbnail_max_height)
end
{thumbnail_max_width, thumbnail_max_height}
end
defp thumbnail_binary(url, body, params) do
{thumbnail_max_width, thumbnail_max_height} = thumbnail_max_dimensions(params)
with true <- Config.get([:media_preview_proxy, :enable_eimp]),
{:ok, [type: image_type, width: source_width, height: source_height]} <-
:eimp.identify(body),
scale_factor <-
Enum.max([source_width / thumbnail_max_width, source_height / thumbnail_max_height]),
{:ok, thumbnail_binary} =
:eimp.convert(body, image_type, [
{:scale, {round(source_width / scale_factor), round(source_height / scale_factor)}}
]) do
{:ok, thumbnail_binary}
else
_ ->
mogrify_dimensions = "#{thumbnail_max_width}x#{thumbnail_max_height}"
with {:ok, path} <- MogrifyHelper.store_as_temporary_file(url, body),
%Mogrify.Image{} <-
MogrifyHelper.in_place_resize_to_limit(path, mogrify_dimensions),
{:ok, thumbnail_binary} <- File.read(path),
_ <- File.rm(path) do
{:ok, thumbnail_binary}
else
_ -> :error
end
end
end
defp handle_preview("image/" <> _ = content_type, %{params: params} = conn, url) do
with {:ok, %{status: status, body: image_contents}} when status in 200..299 <-
url
|> MediaProxy.url()
|> Tesla.get(opts: [adapter: [timeout: preview_timeout()]]),
{:ok, thumbnail_binary} <- thumbnail_binary(url, image_contents, params) do
conn
|> put_resp_header("content-type", content_type)
|> send_resp(200, thumbnail_binary)
else
{_, %{status: _}} ->
send_resp(conn, :failed_dependency, "Can't fetch the image.")
{:error, :recv_response_timeout} ->
send_resp(conn, :failed_dependency, "Downstream timeout.")
_ ->
send_resp(conn, :failed_dependency, "Can't handle image preview.")
end
end
defp handle_preview(content_type, conn, _url) do
send_resp(conn, :unprocessable_entity, "Unsupported content type: #{content_type}.")
end
defp preview_head_request_timeout do
Config.get([:media_preview_proxy, :proxy_opts, :head_request_max_read_duration]) ||
preview_timeout()
end
defp preview_timeout do
Config.get([:media_preview_proxy, :proxy_opts, :max_read_duration]) ||
Config.get([:media_proxy, :proxy_opts, :max_read_duration]) ||
ReverseProxy.max_read_duration_default()
end
end