git.squeep.com Git - akkoma/blob - lib/pleroma/web/metadata/opengraph.ex

   1 defmodule Pleroma.Web.Metadata.Providers.OpenGraph do
   2   alias Pleroma.Web.Metadata.Providers.Provider
   3   alias Pleroma.{HTML, Formatter, User}
   4   alias Pleroma.Web.MediaProxy
   5
   6   @behaviour Provider
   7
   8   @impl Provider
   9   def build_tags(%{activity: activity, user: user}) do
  10     with truncated_content = scrub_html_and_truncate(activity.data["object"]["content"]) do
  11       attachments = build_attachments(activity)
  12       [
  13         {:meta,
  14          [
  15            property: "og:title",
  16            content: user_name_string(user)
  17          ], []},
  18         {:meta, [property: "og:url", content: activity.data["id"]], []},
  19         {:meta, [property: "og:description", content: truncated_content], []},
  20         {:meta, [property: "twitter:card", content: "summary"], []}
  21       ] ++ if attachments == [] do [
  22         {:meta, [property: "og:image", content: attachment_url(User.avatar_url(user))], []},
  23         {:meta, [property: "og:image:width", content: 120], []},
  24         {:meta, [property: "og:image:height", content: 120], []} ] else attachments end
  25     end
  26   end
  27
  28   @impl Provider
  29   def build_tags(%{user: user}) do
  30     with truncated_bio = scrub_html_and_truncate(user.bio || "") do
  31       [
  32         {:meta,
  33          [
  34            property: "og:title",
  35            content: user_name_string(user)
  36          ], []},
  37         {:meta, [property: "og:url", content: User.profile_url(user)], []},
  38         {:meta, [property: "og:description", content: truncated_bio], []},
  39         {:meta, [property: "og:image", content: attachment_url(User.avatar_url(user))], []},
  40         {:meta, [property: "og:image:width", content: 120], []},
  41         {:meta, [property: "og:image:height", content: 120], []},
  42         {:meta, [property: "twitter:card", content: "summary"], []}
  43       ]
  44     end
  45   end
  46
  47   defp build_attachments(activity) do
  48     Enum.reduce(activity.data["object"]["attachment"], [], fn attachment, acc ->
  49       rendered_tags =
  50         Enum.map(attachment["url"], fn url ->
  51           media_type =
  52             Enum.find(["image", "audio", "video"], fn media_type ->
  53               String.starts_with?(url["mediaType"], media_type)
  54             end)
  55
  56           if media_type do
  57             {:meta, [property: "og:" <> media_type, content: attachment_url(url["href"])], []}
  58           else
  59             nil
  60           end
  61         end)
  62
  63       Enum.reject(rendered_tags, &is_nil/1)
  64       acc ++ rendered_tags
  65     end)
  66   end
  67
  68   defp scrub_html_and_truncate(content) do
  69     content
  70     # html content comes from DB already encoded, decode first and scrub after
  71     |> HtmlEntities.decode()
  72     |> String.replace(~r/<br\s?\/?>/, " ")
  73     |> HTML.strip_tags()
  74     |> Formatter.truncate()
  75   end
  76
  77   defp attachment_url(url) do
  78     MediaProxy.url(url)
  79   end
  80
  81   defp user_name_string(user) do
  82     "#{user.name}" <>
  83       if user.local do
  84         "(@#{user.nickname}@#{Pleroma.Web.Endpoint.host()})"
  85       else
  86         "(@#{user.nickname})"
  87       end
  88   end
  89 end