Introduce relay

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

lib/service/html.ex

@@ -0,0 +1,73 @@
+# Portions of this file are derived from Pleroma:
+# Copyright © 2017-2019 Pleroma Authors <https://pleroma.social>
+# SPDX-License-Identifier: AGPL-3.0-only
+# Upstream: https://git.pleroma.social/pleroma/pleroma/blob/develop/lib/pleroma/html.ex
+
+defmodule Mobilizon.Service.HTML do
+  @moduledoc """
+  Service to filter tags out of HTML content
+  """
+  alias HtmlSanitizeEx.Scrubber
+  alias Mobilizon.Service.HTML.Scrubber.Default
+
+  def filter_tags(html), do: Scrubber.scrub(html, Default)
+end
+
+defmodule Mobilizon.Service.HTML.Scrubber.Default do
+  @moduledoc "Custom strategy to filter HTML content"
+
+  require HtmlSanitizeEx.Scrubber.Meta
+  alias HtmlSanitizeEx.Scrubber.Meta
+  # credo:disable-for-previous-line
+  # No idea how to fix this one…
+
+  Meta.remove_cdata_sections_before_scrub()
+  Meta.strip_comments()
+
+  Meta.allow_tag_with_uri_attributes("a", ["href", "data-user", "data-tag"], ["https", "http"])
+
+  Meta.allow_tag_with_this_attribute_values("a", "class", [
+    "hashtag",
+    "u-url",
+    "mention",
+    "u-url mention",
+    "mention u-url"
+  ])
+
+  Meta.allow_tag_with_this_attribute_values("a", "rel", [
+    "tag",
+    "nofollow",
+    "noopener",
+    "noreferrer"
+  ])
+
+  Meta.allow_tag_with_these_attributes("a", ["name", "title"])
+
+  Meta.allow_tag_with_these_attributes("abbr", ["title"])
+
+  Meta.allow_tag_with_these_attributes("b", [])
+  Meta.allow_tag_with_these_attributes("blockquote", [])
+  Meta.allow_tag_with_these_attributes("br", [])
+  Meta.allow_tag_with_these_attributes("code", [])
+  Meta.allow_tag_with_these_attributes("del", [])
+  Meta.allow_tag_with_these_attributes("em", [])
+  Meta.allow_tag_with_these_attributes("i", [])
+  Meta.allow_tag_with_these_attributes("li", [])
+  Meta.allow_tag_with_these_attributes("ol", [])
+  Meta.allow_tag_with_these_attributes("p", [])
+  Meta.allow_tag_with_these_attributes("pre", [])
+  Meta.allow_tag_with_these_attributes("strong", [])
+  Meta.allow_tag_with_these_attributes("u", [])
+  Meta.allow_tag_with_these_attributes("ul", [])
+
+  Meta.allow_tag_with_this_attribute_values("span", "class", ["h-card"])
+  Meta.allow_tag_with_these_attributes("span", [])
+
+  Meta.allow_tag_with_these_attributes("h1", [])
+  Meta.allow_tag_with_these_attributes("h2", [])
+  Meta.allow_tag_with_these_attributes("h3", [])
+  Meta.allow_tag_with_these_attributes("h4", [])
+  Meta.allow_tag_with_these_attributes("h5", [])
+
+  Meta.strip_everything_not_covered()
+end