open_graph.ex (4992B)
- # Pleroma: A lightweight social networking server
- # Copyright © 2017-2022 Pleroma Authors <https://pleroma.social/>
- # SPDX-License-Identifier: AGPL-3.0-only
- defmodule Pleroma.Web.Metadata.Providers.OpenGraph do
- alias Pleroma.User
- alias Pleroma.Web.MediaProxy
- alias Pleroma.Web.Metadata
- alias Pleroma.Web.Metadata.Providers.Provider
- alias Pleroma.Web.Metadata.Utils
- @behaviour Provider
- @media_types ["image", "audio", "video"]
- @impl Provider
- def build_tags(%{
- object: object,
- url: url,
- user: user
- }) do
- attachments = build_attachments(object)
- scrubbed_content = Utils.scrub_html_and_truncate(object)
- [
- {:meta,
- [
- property: "og:title",
- content: Utils.user_name_string(user)
- ], []},
- {:meta, [property: "og:url", content: url], []},
- {:meta,
- [
- property: "og:description",
- content: scrubbed_content
- ], []},
- {:meta, [property: "og:type", content: "article"], []}
- ] ++
- if attachments == [] or Metadata.activity_nsfw?(object) do
- [
- {:meta, [property: "og:image", content: MediaProxy.preview_url(User.avatar_url(user))],
- []},
- {:meta, [property: "og:image:width", content: 150], []},
- {:meta, [property: "og:image:height", content: 150], []}
- ]
- else
- attachments
- end
- end
- @impl Provider
- def build_tags(%{user: user}) do
- with truncated_bio = Utils.scrub_html_and_truncate(user.bio) do
- [
- {:meta,
- [
- property: "og:title",
- content: Utils.user_name_string(user)
- ], []},
- {:meta, [property: "og:url", content: user.uri || user.ap_id], []},
- {:meta, [property: "og:description", content: truncated_bio], []},
- {:meta, [property: "og:type", content: "article"], []},
- {:meta, [property: "og:image", content: MediaProxy.preview_url(User.avatar_url(user))],
- []},
- {:meta, [property: "og:image:width", content: 150], []},
- {:meta, [property: "og:image:height", content: 150], []}
- ]
- end
- end
- defp build_attachments(%{data: %{"attachment" => attachments}}) do
- Enum.reduce(attachments, [], fn attachment, acc ->
- rendered_tags =
- Enum.reduce(attachment["url"], [], fn url, acc ->
- # TODO: Whatsapp only wants JPEG or PNGs. It seems that if we add a second og:image
- # object when a Video or GIF is attached it will display that in Whatsapp Rich Preview.
- case Utils.fetch_media_type(@media_types, url["mediaType"]) do
- "audio" ->
- [
- {:meta, [property: "og:audio", content: MediaProxy.url(url["href"])], []}
- | acc
- ]
- # Not using preview_url for this. It saves bandwidth, but the image dimensions will
- # be wrong. We generate it on the fly and have no way to capture or analyze the
- # image to get the dimensions. This can be an issue for apps/FEs rendering images
- # in timelines too, but you can get clever with the aspect ratio metadata as a
- # workaround.
- "image" ->
- [
- {:meta, [property: "og:image", content: MediaProxy.url(url["href"])], []},
- {:meta, [property: "og:image:alt", content: attachment["name"]], []}
- | acc
- ]
- |> maybe_add_dimensions(url)
- "video" ->
- [
- {:meta, [property: "og:video", content: MediaProxy.url(url["href"])], []}
- | acc
- ]
- |> maybe_add_dimensions(url)
- |> maybe_add_video_thumbnail(url)
- _ ->
- acc
- end
- end)
- acc ++ rendered_tags
- end)
- end
- defp build_attachments(_), do: []
- # We can use url["mediaType"] to dynamically fill the metadata
- defp maybe_add_dimensions(metadata, url) do
- type = url["mediaType"] |> String.split("/") |> List.first()
- cond do
- !is_nil(url["height"]) && !is_nil(url["width"]) ->
- metadata ++
- [
- {:meta, [property: "og:#{type}:width", content: "#{url["width"]}"], []},
- {:meta, [property: "og:#{type}:height", content: "#{url["height"]}"], []}
- ]
- true ->
- metadata
- end
- end
- # Media Preview Proxy makes thumbnails of videos without resizing, so we can trust the
- # width and height of the source video.
- defp maybe_add_video_thumbnail(metadata, url) do
- cond do
- Pleroma.Config.get([:media_preview_proxy, :enabled], false) ->
- metadata ++
- [
- {:meta, [property: "og:image:width", content: "#{url["width"]}"], []},
- {:meta, [property: "og:image:height", content: "#{url["height"]}"], []},
- {:meta, [property: "og:image", content: MediaProxy.preview_url(url["href"])], []}
- ]
- true ->
- metadata
- end
- end
- end