+defmodule Pleroma.Web.Metadata do
+ alias Phoenix.HTML
+ alias Pleroma.{Web, Formatter}
+ alias Pleroma.{User, Activity}
+ alias Pleroma.Web.MediaProxy
+
+ def build_tags(activity, user, url) do
+ Enum.concat([
+ if(meta_enabled?(:opengraph), do: opengraph_tags(activity, user), else: []),
+ if(meta_enabled?(:oembed), do: oembed_links(url), else: [])
+ ])
+ |> Enum.map(&to_tag/1)
+ |> Enum.map(&HTML.safe_to_string/1)
+ |> Enum.join("\n")
+ end
+
+ def meta_enabled?(type) do
+ config = Pleroma.Config.get(:metadata, [])
+ Keyword.get(config, type, false)
+ end
+
+ def to_tag(data) do
+ with {name, attrs, _content = []} <- data do
+ HTML.Tag.tag(name, attrs)
+ else
+ {name, attrs, content} ->
+ HTML.Tag.content_tag(name, content, attrs)
+
+ _ ->
+ raise ArgumentError, message: "make_tag invalid args"
+ end
+ end
+
+ defp oembed_links(url) do
+ Enum.map(["xml", "json"], fn format ->
+ href = HTML.raw(oembed_path(url, format))
+ { :link, [ type: ["application/#{format}+oembed"], href: href, rel: 'alternate'], [] }
+ end)
+ end
+
+ defp opengraph_tags(activity, user) do
+ with image = User.avatar_url(user) |> MediaProxy.url(),
+ truncated_content = Formatter.truncate(activity.data["object"]["content"]),
+ domain = Pleroma.Config.get([:instance, :domain], "UNKNOWN_DOMAIN") do
+ [
+ {:meta,
+ [
+ property: "og:title",
+ content: "#{user.name} (@#{user.nickname}@#{domain}) post ##{activity.id}"
+ ], []},
+ {:meta, [property: "og:url", content: activity.data["id"]], []},
+ {:meta, [property: "og:description", content: truncated_content],
+ []},
+ {:meta, [property: "og:image", content: image], []},
+ {:meta, [property: "og:image:width", content: 120], []},
+ {:meta, [property: "og:image:height", content: 120], []},
+ {:meta, [property: "twitter:card", content: "summary"], []}
+ ]
+ end
+ end
+
+ defp oembed_path(url, format) do
+ query = URI.encode_query(%{url: url, format: format})
+ "#{Web.base_url()}/oembed?#{query}"
+ end
+end
\ No newline at end of file