akkoma/lib/pleroma/web/activity_pub/transmogrifier.ex
2018-02-18 13:06:51 +01:00

150 lines
4.3 KiB
Elixir

defmodule Pleroma.Web.ActivityPub.Transmogrifier do
@moduledoc """
A module to handle coding from internal to wire ActivityPub and back.
"""
alias Pleroma.User
alias Pleroma.Object
alias Pleroma.Activity
alias Pleroma.Web.ActivityPub.ActivityPub
@doc """
Modifies an incoming AP object (mastodon format) to our internal format.
"""
def fix_object(object) do
object
|> Map.put("actor", object["attributedTo"])
|> fix_attachments
end
def fix_attachments(object) do
attachments = (object["attachment"] || [])
|> Enum.map(fn (data) ->
url = [%{"type" => "Link", "mediaType" => data["mediaType"], "href" => data["url"]}]
Map.put(data, "url", url)
end)
object
|> Map.put("attachment", attachments)
end
# TODO: validate those with a Ecto scheme
# - tags
# - emoji
def handle_incoming(%{"type" => "Create", "object" => %{"type" => "Note"} = object} = data) do
with %User{} = user <- User.get_or_fetch_by_ap_id(data["actor"]) do
object = fix_object(data["object"])
params = %{
to: data["to"],
object: object,
actor: user,
context: data["object"]["conversation"],
local: false,
published: data["published"],
additional: Map.take(data, [
"cc",
"id"
])
}
ActivityPub.create(params)
else
_e -> :error
end
end
def handle_incoming(%{"type" => "Follow", "object" => followed, "actor" => follower, "id" => id} = data) do
with %User{local: true} = followed <- User.get_cached_by_ap_id(followed),
%User{} = follower <- User.get_or_fetch_by_ap_id(follower),
{:ok, activity} <- ActivityPub.follow(follower, followed, id, false) do
ActivityPub.accept(%{to: [follower.ap_id], actor: followed.ap_id, object: data, local: true})
User.follow(follower, followed)
{:ok, activity}
else
_e -> :error
end
end
def handle_incoming(%{"type" => "Like", "object" => object_id, "actor" => actor, "id" => id} = data) do
with %User{} = actor <- User.get_or_fetch_by_ap_id(actor),
%Object{} = object <- Object.get_by_ap_id(object_id),
{:ok, activity, object} <- ActivityPub.like(actor, object, id, false) do
{:ok, activity}
else
_e -> :error
end
end
def handle_incoming(%{"type" => "Announce", "object" => object_id, "actor" => actor, "id" => id} = data) do
with %User{} = actor <- User.get_or_fetch_by_ap_id(actor),
{:ok, object} <- get_obj_helper(object_id) || ActivityPub.fetch_object_from_id(object_id),
{:ok, activity, object} <- ActivityPub.announce(actor, object, id, false) do
{:ok, activity}
else
_e -> :error
end
end
# TODO
# Accept
# Undo
def handle_incoming(_), do: :error
def get_obj_helper(id) do
if object = Object.get_by_ap_id(id), do: {:ok, object}, else: nil
end
@doc
"""
internal -> Mastodon
"""
def prepare_outgoing(%{"type" => "Create", "object" => %{"type" => "Note"} = object} = data) do
object = object
|> add_mention_tags
|> add_attributed_to
|> prepare_attachments
data = data
|> Map.put("object", object)
|> Map.put("@context", "https://www.w3.org/ns/activitystreams")
{:ok, data}
end
def prepare_outgoing(%{"type" => type} = data) when type in ["Follow", "Accept", "Like", "Announce"] do
data = data
|> Map.put("@context", "https://www.w3.org/ns/activitystreams")
{:ok, data}
end
def add_mention_tags(object) do
mentions = object["to"]
|> Enum.map(fn (ap_id) -> User.get_cached_by_ap_id(ap_id) end)
|> Enum.filter(&(&1))
|> Enum.map(fn(user) -> %{"type" => "Mention", "href" => user.ap_id, "name" => "@#{user.nickname}"} end)
tags = object["tag"] || []
object
|> Map.put("tag", tags ++ mentions)
end
def add_attributed_to(object) do
attributedTo = object["attributedTo"] || object["actor"]
object
|> Map.put("attributedTo", attributedTo)
end
def prepare_attachments(object) do
attachments = (object["attachment"] || [])
|> Enum.map(fn (data) ->
[%{"mediaType" => media_type, "href" => href} | _] = data["url"]
%{"url" => href, "mediaType" => media_type, "name" => data["name"], "type" => "Document"}
end)
object
|> Map.put("attachment", attachments)
end
end