debianize-mobilizon/lib/service/rich_media/parsers/fallback.ex
Thomas Citharel 4144e9ffd0
Introduce group basic federation, event new page and notifications
Signed-off-by: Thomas Citharel <tcit@tcit.fr>
2020-06-03 16:01:26 +02:00

42 lines
1.2 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.Fallback do
@moduledoc """
Module to parse fallback data in HTML pages (plain old title and meta description)
"""
@spec parse(String.t(), map()) :: {:ok, map()} | {:error, String.t()}
def parse(html, data) do
data =
data
|> maybe_put(html, :title)
|> maybe_put(html, :description)
if Enum.empty?(data) do
{:error, "Not even a title"}
else
{:ok, data}
end
end
defp maybe_put(meta, html, attr) do
case get_page(html, attr) do
"" -> meta
content -> Map.put_new(meta, attr, content)
end
end
defp get_page(html, :title) do
html |> Floki.find("html head title") |> List.first() |> Floki.text() |> String.trim()
end
defp get_page(html, :description) do
case html |> Floki.find("html head meta[name='description']") |> List.first() do
nil -> ""
elem -> elem |> Floki.attribute("content") |> List.first() |> String.trim()
end
end
end