git.squeep.com Git - akkoma/blob - lib/pleroma/web/activity_pub/transmogrifier.ex

   1 defmodule Pleroma.Web.ActivityPub.Transmogrifier do
   2   @moduledoc """
   3   A module to handle coding from internal to wire ActivityPub and back.
   4   """
   5   alias Pleroma.User
   6   alias Pleroma.Web.ActivityPub.ActivityPub
   7
   8   @doc """
   9   Modifies an incoming AP object (mastodon format) to our internal format.
  10   """
  11   def fix_object(object) do
  12     object
  13     |> Map.put("actor", object["attributedTo"])
  14     |> fix_attachments
  15   end
  16
  17   def fix_attachments(object) do
  18     attachments = object["attachment"] || []
  19     |> Enum.map(fn (data) ->
  20       url = [%{"type" => "Link", "mediaType" => data["mediaType"], "url" => data["url"]}]
  21       Map.put(data, "url", url)
  22     end)
  23
  24     object
  25     |> Map.put("attachment", attachments)
  26   end
  27
  28   # TODO: validate those with a Ecto scheme
  29   # - tags
  30   # - emoji
  31   def handle_incoming(%{"type" => "Create", "object" => %{"type" => "Note"} = object} = data) do
  32     with %User{} = user <- User.get_or_fetch_by_ap_id(data["actor"]) do
  33       object = fix_object(data["object"])
  34       params = %{
  35         to: data["to"],
  36         object: object,
  37         actor: user,
  38         context: data["object"]["conversation"],
  39         local: false,
  40         published: data["published"],
  41         additional: Map.take(data, [
  42               "cc",
  43               "id"
  44             ])
  45       }
  46
  47       ActivityPub.create(params)
  48     else
  49       _e -> :error
  50     end
  51   end
  52
  53   def handle_incoming(%{"type" => "Follow", "object" => followed, "actor" => follower, "id" => id} = data) do
  54     with %User{local: true} = followed <- User.get_cached_by_ap_id(followed),
  55          %User{} = follower <- User.get_or_fetch_by_ap_id(follower),
  56          {:ok, activity} <- ActivityPub.follow(follower, followed, id, false) do
  57       ActivityPub.accept(%{to: [follower.ap_id], actor: followed.ap_id, object: data, local: true})
  58       User.follow(follower, followed)
  59       {:ok, activity}
  60     else
  61       _e -> :error
  62     end
  63   end
  64
  65   def handle_incoming(_), do: :error
  66
  67   @doc
  68   """
  69   internal -> Mastodon
  70   """
  71   def prepare_outgoing(%{"type" => "Create", "object" => %{"type" => "Note"} = object} = data) do
  72     object = object
  73     |> add_mention_tags
  74     |> add_attributed_to
  75     |> prepare_attachments
  76
  77     data = data
  78     |> Map.put("object", object)
  79     |> Map.put("@context", "https://www.w3.org/ns/activitystreams")
  80
  81     {:ok, data}
  82   end
  83
  84   def prepare_outgoing(%{"type" => type} = data) when type in ["Follow", "Accept"] do
  85     data = data
  86     |> Map.put("@context", "https://www.w3.org/ns/activitystreams")
  87
  88     {:ok, data}
  89   end
  90
  91   def add_mention_tags(object) do
  92     mentions = object["to"]
  93     |> Enum.map(fn (ap_id) -> User.get_cached_by_ap_id(ap_id) end)
  94     |> Enum.filter(&(&1))
  95     |> Enum.map(fn(user) -> %{"type" => "Mention", "href" => user.ap_id, "name" => "@#{user.nickname}"} end)
  96
  97     tags = object["tag"] || []
  98
  99     object
 100     |> Map.put("tag", tags ++ mentions)
 101   end
 102
 103   def add_attributed_to(object) do
 104     attributedTo = object["attributedTo"] || object["actor"]
 105
 106     object
 107     |> Map.put("attributedTo", attributedTo)
 108   end
 109
 110   def prepare_attachments(object) do
 111     attachments = (object["attachment"] || [])
 112     |> Enum.map(fn (data) ->
 113       [%{"mediaType" => media_type, "href" => href} | _] = data["url"]
 114       %{"url" => href, "mediaType" => media_type, "name" => data["name"], "type" => "Document"}
 115     end)
 116
 117     object
 118     |> Map.put("attachment", attachments)
 119   end
 120 end