debianize-mobilizon/lib/service/rich_media/parsers/twitter_card.ex
Thomas Citharel f0141c97e8
Refactor rich media parsers to restrict the allowed properties
Signed-off-by: Thomas Citharel <tcit@tcit.fr>
2021-01-22 19:44:59 +01:00

59 lines
1.5 KiB
Elixir

# Portions of this file are derived from Pleroma:
# Pleroma: A lightweight social networking server
# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Mobilizon.Service.RichMedia.Parsers.TwitterCard do
@moduledoc """
Module to parse Twitter tags data in HTML pages
"""
alias Mobilizon.Service.RichMedia.Parsers.MetaTagsParser
require Logger
@twitter_card_properties [
:card,
:site,
:creator,
:title,
:description,
:image,
:"image:alt"
]
@spec parse(String.t(), map()) :: {:ok, map()} | {:error, String.t()}
def parse(html, data) do
Logger.debug("Using Twitter card parser")
with {:ok, data} <- parse_name_attrs(data, html),
{:ok, data} <- parse_property_attrs(data, html),
data <- transform_tags(data) do
Logger.debug("Data found with Twitter card parser")
Logger.debug(inspect(data))
data
end
end
defp parse_name_attrs(data, html) do
MetaTagsParser.parse(html, data, "twitter", %{}, :name, :content, [:"twitter:card"])
end
defp parse_property_attrs({_, data}, html) do
MetaTagsParser.parse(
html,
data,
"twitter",
"No twitter card metadata found",
:property,
:content,
@twitter_card_properties
)
end
defp transform_tags(data) do
data
|> Enum.reject(fn {_, v} -> is_nil(v) end)
|> Map.new()
|> Map.update(:image_remote_url, Map.get(data, :image), & &1)
end
end