[#2497] Media preview proxy: misc. improvements (static param support, dynamic fifo pipe path), refactoring.

lib/pleroma/helpers/media_helper.ex

@@ -9,8 +9,6 @@ defmodule Pleroma.Helpers.MediaHelper do
 
   alias Pleroma.HTTP
 
-  @tmp_base "/tmp/pleroma-media_preview-pipe"
-
   def image_resize(url, options) do
     with executable when is_binary(executable) <- System.find_executable("convert"),
          {:ok, args} <- prepare_image_resize_args(options),
@@ -103,7 +101,7 @@ defmodule Pleroma.Helpers.MediaHelper do
   end
 
   defp mkfifo do
-    path = "#{@tmp_base}#{to_charlist(:erlang.phash2(self()))}"
+    path = Path.join(System.tmp_dir!(), "pleroma-media-preview-pipe-#{Ecto.UUID.generate()}")
 
     case System.cmd("mkfifo", [path]) do
       {_, 0} ->

lib/pleroma/helpers/uri_helper.ex

@@ -3,14 +3,17 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Helpers.UriHelper do
-  def append_uri_params(uri, appended_params) do
+  def modify_uri_params(uri, overridden_params, deleted_params \\ []) do
     uri = URI.parse(uri)
-    appended_params = for {k, v} <- appended_params, into: %{}, do: {to_string(k), v}
-    existing_params = URI.query_decoder(uri.query || "") |> Enum.into(%{})
-    updated_params_keys = Enum.uniq(Map.keys(existing_params) ++ Map.keys(appended_params))
+
+    existing_params = URI.query_decoder(uri.query || "") |> Map.new()
+    overridden_params = Map.new(overridden_params, fn {k, v} -> {to_string(k), v} end)
+    deleted_params = Enum.map(deleted_params, &to_string/1)
 
     updated_params =
-      for k <- updated_params_keys, do: {k, appended_params[k] || existing_params[k]}
+      existing_params
+      |> Map.merge(overridden_params)
+      |> Map.drop(deleted_params)
 
     uri
     |> Map.put(:query, URI.encode_query(updated_params))