mobilizon/lib/service/metadata/post.ex

80 lines
2.5 KiB
Elixir

defimpl Mobilizon.Service.Metadata, for: Mobilizon.Posts.Post do
alias Phoenix.HTML
alias Phoenix.HTML.Tag
alias Mobilizon.Actors.Actor
alias Mobilizon.Medias.{File, Media}
alias Mobilizon.Posts.Post
alias Mobilizon.Web.Endpoint
alias Mobilizon.Web.JsonLD.ObjectView
alias Mobilizon.Web.Router.Helpers, as: Routes
import Mobilizon.Service.Metadata.Utils, only: [process_description: 2, strip_tags: 1]
def build_tags(%Post{} = post, locale \\ "en") do
post = Map.put(post, :body, process_description(post.body, locale))
tags =
[
Tag.tag(:meta, property: "og:title", content: post.title),
Tag.tag(:meta, property: "og:url", content: post.url),
Tag.tag(:meta, property: "og:description", content: post.body),
Tag.tag(:meta, property: "og:type", content: "article"),
Tag.tag(:meta, property: "twitter:card", content: "summary"),
# Tell Search Engines what's the origin
Tag.tag(:link, rel: "canonical", href: post.url)
]
|> maybe_add_post_picture(post)
breadcrumbs = %{
"@context" => "https://schema.org",
"@type" => "BreadcrumbList",
"itemListElement" => [
%{
"@type" => "ListItem",
"position" => 1,
"name" => Actor.display_name(post.attributed_to),
"item" =>
Endpoint
|> Routes.page_url(
:actor,
Actor.preferred_username_and_domain(post.attributed_to)
)
|> URI.decode()
},
%{
"@type" => "ListItem",
"position" => 2,
"name" => post.title
}
]
}
tags ++
[
Tag.tag(:meta, property: "twitter:card", content: "summary_large_image"),
~s{<script type="application/ld+json">#{Jason.encode!(breadcrumbs)}</script>}
|> HTML.raw(),
~s{<script type="application/ld+json">#{json(post)}</script>} |> HTML.raw()
]
end
# Insert JSON-LD schema by hand because Tag.content_tag wants to escape it
defp json(%Post{title: title} = post) do
"post.json"
|> ObjectView.render(%{post: %{post | title: strip_tags(title)}})
|> Jason.encode!()
end
@spec maybe_add_post_picture(list(), Post.t()) :: list()
defp maybe_add_post_picture(tags, %Post{picture: %Media{file: %File{url: url}}}),
do:
tags ++
[
Tag.tag(:meta,
property: "og:image",
content: url
)
]
defp maybe_add_post_picture(tags, _), do: tags
end