debianize-mobilizon/lib/service/activity_pub/transmogrifier.ex
2019-09-09 00:52:49 +02:00

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# Portions of this file are derived from Pleroma:
# Copyright © 2017-2018 Pleroma Authors <https://pleroma.social>
# SPDX-License-Identifier: AGPL-3.0-only
# Upstream: https://git.pleroma.social/pleroma/pleroma/blob/develop/lib/pleroma/web/activity_pub/transmogrifier.ex
defmodule Mobilizon.Service.ActivityPub.Transmogrifier do
@moduledoc """
A module to handle coding from internal to wire ActivityPub and back.
"""
alias Mobilizon.Actors
alias Mobilizon.Actors.{Actor, Follower}
alias Mobilizon.Events
alias Mobilizon.Events.{Event, Comment, Participant}
alias Mobilizon.Service.ActivityPub
alias Mobilizon.Service.ActivityPub.Utils
alias Mobilizon.Service.ActivityPub.Visibility
require Logger
def get_actor(%{"actor" => actor}) when is_binary(actor) do
actor
end
def get_actor(%{"actor" => actor}) when is_list(actor) do
if is_binary(Enum.at(actor, 0)) do
Enum.at(actor, 0)
else
Enum.find(actor, fn %{"type" => type} -> type in ["Person", "Service", "Application"] end)
|> Map.get("id")
end
end
def get_actor(%{"actor" => %{"id" => id}}) when is_bitstring(id) do
id
end
def get_actor(%{"actor" => nil, "attributedTo" => actor}) when not is_nil(actor) do
get_actor(%{"actor" => actor})
end
@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
|> fix_in_reply_to
# |> fix_tag
end
def fix_in_reply_to(%{"inReplyTo" => in_reply_to} = object)
when not is_nil(in_reply_to) and is_bitstring(in_reply_to) do
in_reply_to |> do_fix_in_reply_to(object)
end
def fix_in_reply_to(%{"inReplyTo" => in_reply_to} = object)
when not is_nil(in_reply_to) and is_map(in_reply_to) do
if is_bitstring(in_reply_to["id"]) do
in_reply_to["id"] |> do_fix_in_reply_to(object)
end
end
def fix_in_reply_to(%{"inReplyTo" => in_reply_to} = object)
when not is_nil(in_reply_to) and is_list(in_reply_to) do
if is_bitstring(Enum.at(in_reply_to, 0)) do
in_reply_to |> Enum.at(0) |> do_fix_in_reply_to(object)
end
end
def fix_in_reply_to(%{"inReplyTo" => in_reply_to} = object)
when not is_nil(in_reply_to) do
Logger.warn("inReplyTo ID seem incorrect: #{inspect(in_reply_to)}")
do_fix_in_reply_to("", object)
end
def fix_in_reply_to(object), do: object
def do_fix_in_reply_to(in_reply_to_id, object) do
case fetch_obj_helper(in_reply_to_id) do
{:ok, replied_object} ->
object
|> Map.put("inReplyTo", replied_object.url)
{:error, {:error, :not_supported}} ->
Logger.info("Object reply origin has not a supported type")
object
e ->
Logger.warn("Couldn't fetch #{in_reply_to_id} #{inspect(e)}")
object
end
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
def fix_tag(object) do
tags =
(object["tag"] || [])
|> Enum.filter(fn data -> data["type"] == "Hashtag" and data["name"] end)
|> Enum.map(fn data -> String.slice(data["name"], 1..-1) end)
combined = (object["tag"] || []) ++ tags
object
|> Map.put("tag", combined)
end
def handle_incoming(%{"id" => nil}), do: :error
def handle_incoming(%{"id" => ""}), do: :error
def handle_incoming(%{"type" => "Flag"} = data) do
with params <- Mobilizon.Service.ActivityPub.Converters.Flag.as_to_model(data) do
params = %{
reporter_url: params["reporter"].url,
reported_actor_url: params["reported"].url,
comments_url: params["comments"] |> Enum.map(& &1.url),
content: params["content"] || "",
additional: %{
"cc" => [params["reported"].url]
}
}
ActivityPub.flag(params)
end
end
def handle_incoming(%{"type" => "Create", "object" => %{"type" => "Note"} = object} = data) do
Logger.info("Handle incoming to create notes")
with {:ok, %Actor{} = actor} <- ActivityPub.get_or_fetch_by_url(data["actor"]) do
Logger.debug("found actor")
Logger.debug(inspect(actor))
params = %{
to: data["to"],
object: object |> fix_object,
actor: actor,
local: false,
published: data["published"],
additional:
Map.take(data, [
"cc",
"id"
])
}
ActivityPub.create(params)
end
end
def handle_incoming(%{"type" => "Create", "object" => %{"type" => "Event"} = object} = data) do
Logger.info("Handle incoming to create event")
with {:ok, %Actor{} = actor} <- ActivityPub.get_or_fetch_by_url(data["actor"]) do
Logger.debug("found actor")
Logger.debug(inspect(actor))
params = %{
to: data["to"],
object: object |> fix_object,
actor: actor,
local: false,
published: data["published"],
additional:
Map.take(data, [
"cc",
"id"
])
}
ActivityPub.create(params)
end
end
def handle_incoming(
%{"type" => "Follow", "object" => followed, "actor" => follower, "id" => id} = _data
) do
with {:ok, %Actor{} = followed} <- ActivityPub.get_or_fetch_by_url(followed, true),
{:ok, %Actor{} = follower} <- ActivityPub.get_or_fetch_by_url(follower),
{:ok, activity, object} <- ActivityPub.follow(follower, followed, id, false) do
{:ok, activity, object}
else
e ->
Logger.warn("Unable to handle Follow activity #{inspect(e)}")
:error
end
end
def handle_incoming(
%{
"type" => "Accept",
"object" => accepted_object,
"actor" => _actor,
"id" => id
} = data
) do
with actor_url <- get_actor(data),
{:ok, %Actor{} = actor} <- ActivityPub.get_or_fetch_by_url(actor_url),
{:object_not_found, {:ok, activity, object}} <-
{:object_not_found,
do_handle_incoming_accept_following(accepted_object, actor) ||
do_handle_incoming_accept_join(accepted_object, actor)} do
{:ok, activity, object}
else
{:object_not_found, nil} ->
Logger.warn(
"Unable to process Accept activity #{inspect(id)}. Object #{inspect(accepted_object)} wasn't found."
)
:error
e ->
Logger.warn(
"Unable to process Accept activity #{inspect(id)} for object #{inspect(accepted_object)} only returned #{
inspect(e)
}"
)
:error
end
end
def handle_incoming(
%{"type" => "Reject", "object" => rejected_object, "actor" => _actor, "id" => id} = data
) do
with actor_url <- get_actor(data),
{:ok, %Actor{} = actor} <- ActivityPub.get_or_fetch_by_url(actor_url),
{:object_not_found, {:ok, activity, object}} <-
{:object_not_found,
do_handle_incoming_reject_following(rejected_object, actor) ||
do_handle_incoming_reject_join(rejected_object, actor)} do
{:ok, activity, object}
else
{:object_not_found, nil} ->
Logger.warn(
"Unable to process Reject activity #{inspect(id)}. Object #{inspect(rejected_object)} wasn't found."
)
:error
e ->
Logger.warn(
"Unable to process Reject activity #{inspect(id)} for object #{inspect(rejected_object)} only returned #{
inspect(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),
# {:ok, object} <-
# fetch_obj_helper(object_id) || ActivityPub.fetch_object_from_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 actor <- get_actor(data),
{:ok, %Actor{} = actor} <- ActivityPub.get_or_fetch_by_url(actor),
{:ok, object} <- fetch_obj_helper_as_activity_streams(object_id),
public <- Visibility.is_public?(data),
{:ok, activity, object} <- ActivityPub.announce(actor, object, id, false, public) do
{:ok, activity, object}
else
e ->
Logger.debug(inspect(e))
:error
end
end
def handle_incoming(
%{"type" => "Update", "object" => %{"type" => object_type} = object, "actor" => _actor_id} =
data
)
when object_type in ["Person", "Group", "Application", "Service", "Organization"] do
case Actors.get_actor_by_url(object["id"]) do
{:ok, %Actor{url: actor_url}} ->
ActivityPub.update(%{
local: false,
to: data["to"] || [],
cc: data["cc"] || [],
object: object,
actor: actor_url
})
e ->
Logger.debug(inspect(e))
:error
end
end
def handle_incoming(
%{"type" => "Update", "object" => %{"type" => "Event"} = object, "actor" => actor} =
_update
) do
with {:ok, %{"actor" => existing_organizer_actor_url} = _existing_event_data} <-
fetch_obj_helper_as_activity_streams(object),
{:ok, %Actor{url: actor_url}} <- actor |> Utils.get_url() |> Actors.get_actor_by_url(),
true <- Utils.get_url(existing_organizer_actor_url) == actor_url do
ActivityPub.update(%{
local: false,
to: object["to"] || [],
cc: object["cc"] || [],
object: object,
actor: actor_url
})
else
e ->
Logger.debug(inspect(e))
:error
end
end
def handle_incoming(
%{
"type" => "Undo",
"object" => %{
"type" => "Announce",
"object" => object_id,
"id" => cancelled_activity_id
},
"actor" => _actor,
"id" => id
} = data
) do
with actor <- get_actor(data),
{:ok, %Actor{} = actor} <- ActivityPub.get_or_fetch_by_url(actor),
{:ok, object} <- fetch_obj_helper_as_activity_streams(object_id),
{:ok, activity, object} <-
ActivityPub.unannounce(actor, object, id, cancelled_activity_id, false) do
{:ok, activity, object}
else
_e -> :error
end
end
def handle_incoming(
%{
"type" => "Undo",
"object" => %{"type" => "Follow", "object" => followed},
"actor" => follower,
"id" => id
} = _data
) do
with {:ok, %Actor{domain: nil} = followed} <- Actors.get_actor_by_url(followed),
{:ok, %Actor{} = follower} <- Actors.get_actor_by_url(follower),
{:ok, activity, object} <- ActivityPub.unfollow(follower, followed, id, false) do
{:ok, activity, object}
else
e ->
Logger.debug(inspect(e))
:error
end
end
# TODO: We presently assume that any actor on the same origin domain as the object being
# deleted has the rights to delete that object. A better way to validate whether or not
# the object should be deleted is to refetch the object URI, which should return either
# an error or a tombstone. This would allow us to verify that a deletion actually took
# place.
def handle_incoming(
%{"type" => "Delete", "object" => object, "actor" => _actor, "id" => _id} = data
) do
object_id = Utils.get_url(object)
with actor <- get_actor(data),
{:ok, %Actor{url: _actor_url}} <- Actors.get_actor_by_url(actor),
{:ok, object} <- fetch_obj_helper(object_id),
# TODO : Validate that DELETE comes indeed form right domain (see above)
# :ok <- contain_origin(actor_url, object.data),
{:ok, activity, object} <- ActivityPub.delete(object, false) do
{:ok, activity, object}
else
e ->
Logger.debug(inspect(e))
:error
end
end
def handle_incoming(
%{"type" => "Join", "object" => object, "actor" => _actor, "id" => _id} = data
) do
with actor <- get_actor(data),
{:ok, %Actor{url: _actor_url} = actor} <- Actors.get_actor_by_url(actor),
{:ok, object} <- fetch_obj_helper(object),
{:ok, activity, object} <- ActivityPub.join(object, actor, false) do
{:ok, activity, object}
else
e ->
Logger.debug(inspect(e))
:error
end
end
def handle_incoming(
%{"type" => "Leave", "object" => object, "actor" => actor, "id" => _id} = data
) do
with actor <- get_actor(data),
{:ok, %Actor{} = actor} <- Actors.get_actor_by_url(actor),
{:ok, object} <- fetch_obj_helper(object),
{:ok, activity, object} <- ActivityPub.leave(object, actor, false) do
{:ok, activity, object}
else
{:only_organizer, true} ->
Logger.warn(
"Actor #{inspect(actor)} tried to leave event #{inspect(object)} but it was the only organizer so we didn't detach it"
)
:error
e ->
Logger.error(inspect(e))
:error
end
end
#
# # TODO
# # Accept
# # Undo
#
# def handle_incoming(
# %{
# "type" => "Undo",
# "object" => %{"type" => "Like", "object" => object_id},
# "actor" => _actor,
# "id" => id
# } = data
# ) do
# with actor <- get_actor(data),
# %Actor{} = actor <- ActivityPub.get_or_fetch_by_url(actor),
# {:ok, object} <- fetch_obj_helper(object_id) || fetch_obj_helper(object_id),
# {:ok, activity, _, _} <- ActivityPub.unlike(actor, object, id, false) do
# {:ok, activity}
# else
# _e -> :error
# end
# end
def handle_incoming(_) do
Logger.info("Handing something not supported")
{:error, :not_supported}
end
@doc """
Handle incoming `Accept` activities wrapping a `Follow` activity
"""
def do_handle_incoming_accept_following(follow_object, %Actor{} = actor) do
with {:follow,
{:ok,
%Follower{approved: false, actor: follower, id: follow_id, target_actor: followed} =
follow}} <-
{:follow, get_follow(follow_object)},
{:same_actor, true} <- {:same_actor, actor.id == followed.id},
{:ok, activity, _} <-
ActivityPub.accept(
%{
to: [follower.url],
actor: actor.url,
object: follow_object,
local: false
},
"#{MobilizonWeb.Endpoint.url()}/accept/follow/#{follow_id}"
),
{:ok, %Follower{approved: true}} <- Actors.update_follower(follow, %{"approved" => true}) do
{:ok, activity, follow}
else
{:follow, _} ->
Logger.debug(
"Tried to handle an Accept activity but it's not containing a Follow activity"
)
nil
{:same_actor} ->
{:error, "Actor who accepted the follow wasn't the target. Quite odd."}
{:ok, %Follower{approved: true} = _follow} ->
{:error, "Follow already accepted"}
end
end
@doc """
Handle incoming `Reject` activities wrapping a `Follow` activity
"""
def do_handle_incoming_reject_following(follow_object, %Actor{} = actor) do
with {:follow,
{:ok,
%Follower{approved: false, actor: follower, id: follow_id, target_actor: followed} =
follow}} <-
{:follow, get_follow(follow_object)},
{:same_actor, true} <- {:same_actor, actor.id == followed.id},
{:ok, activity, _} <-
ActivityPub.reject(
%{
to: [follower.url],
actor: actor.url,
object: follow_object,
local: false
},
"#{MobilizonWeb.Endpoint.url()}/reject/follow/#{follow_id}"
),
{:ok, %Follower{}} <- Actors.delete_follower(follow) do
{:ok, activity, follow}
else
{:follow, _} ->
Logger.debug(
"Tried to handle a Reject activity but it's not containing a Follow activity"
)
nil
{:same_actor} ->
{:error, "Actor who rejected the follow wasn't the target. Quite odd."}
{:ok, %Follower{approved: true} = _follow} ->
{:error, "Follow already accepted"}
end
end
@doc """
Handle incoming `Accept` activities wrapping a `Join` activity on an event
"""
def do_handle_incoming_accept_join(join_object, %Actor{} = actor_accepting) do
with {:join_event,
{:ok,
%Participant{role: :not_approved, actor: actor, id: join_id, event: event} =
participant}} <-
{:join_event, get_participant(join_object)},
# TODO: The actor that accepts the Join activity may another one that the event organizer ?
# Or maybe for groups it's the group that sends the Accept activity
{:same_actor, true} <- {:same_actor, actor_accepting.id == event.organizer_actor_id},
{:ok, activity, _} <-
ActivityPub.accept(
%{
to: [actor.url],
actor: actor_accepting.url,
object: join_object,
local: false
},
"#{MobilizonWeb.Endpoint.url()}/accept/join/#{join_id}"
),
{:ok, %Participant{role: :participant}} <-
Events.update_participant(participant, %{"role" => :participant}) do
{:ok, activity, participant}
else
{:join_event, {:ok, %Participant{role: :participant}}} ->
Logger.debug(
"Tried to handle an Accept activity on a Join activity with a event object but the participant is already validated"
)
nil
{:join_event, _err} ->
Logger.debug(
"Tried to handle an Accept activity but it's not containing a Join activity on a event"
)
nil
{:same_actor} ->
{:error, "Actor who accepted the join wasn't the event organizer. Quite odd."}
{:ok, %Participant{role: :participant} = _follow} ->
{:error, "Participant"}
end
end
@doc """
Handle incoming `Reject` activities wrapping a `Join` activity on an event
"""
def do_handle_incoming_reject_join(join_object, %Actor{} = actor_accepting) do
with {:join_event,
{:ok,
%Participant{role: :not_approved, actor: actor, id: join_id, event: event} =
participant}} <-
{:join_event, get_participant(join_object)},
# TODO: The actor that accepts the Join activity may another one that the event organizer ?
# Or maybe for groups it's the group that sends the Accept activity
{:same_actor, true} <- {:same_actor, actor_accepting.id == event.organizer_actor_id},
{:ok, activity, _} <-
ActivityPub.reject(
%{
to: [actor.url],
actor: actor_accepting.url,
object: join_object,
local: false
},
"#{MobilizonWeb.Endpoint.url()}/reject/join/#{join_id}"
),
{:ok, %Participant{}} <-
Events.delete_participant(participant) do
{:ok, activity, participant}
else
{:join_event, {:ok, %Participant{role: :participant}}} ->
Logger.debug(
"Tried to handle an Reject activity on a Join activity with a event object but the participant is already validated"
)
nil
{:join_event, _err} ->
Logger.debug(
"Tried to handle an Reject activity but it's not containing a Join activity on a event"
)
nil
{:same_actor} ->
{:error, "Actor who rejected the join wasn't the event organizer. Quite odd."}
{:ok, %Participant{role: :participant} = _follow} ->
{:error, "Participant"}
end
end
# TODO: Add do_handle_incoming_accept_join/1 on Groups
defp get_follow(follow_object) do
with follow_object_id when not is_nil(follow_object_id) <- Utils.get_url(follow_object),
{:not_found, %Follower{} = follow} <-
{:not_found, Actors.get_follow_by_url(follow_object_id)} do
{:ok, follow}
else
{:not_found, _err} ->
{:error, "Follow URL not found"}
_ ->
{:error, "ActivityPub ID not found in Accept Follow object"}
end
end
defp get_participant(join_object) do
with join_object_id when not is_nil(join_object_id) <- Utils.get_url(join_object),
{:not_found, %Participant{} = participant} <-
{:not_found, Events.get_participant_by_url(join_object_id)} do
{:ok, participant}
else
{:not_found, _err} ->
{:error, "Participant URL not found"}
_ ->
{:error, "ActivityPub ID not found in Accept Join object"}
end
end
def set_reply_to_uri(%{"inReplyTo" => in_reply_to} = object) do
with false <- String.starts_with?(in_reply_to, "http"),
{:ok, replied_to_object} <- fetch_obj_helper(in_reply_to) do
Map.put(object, "inReplyTo", replied_to_object["external_url"] || in_reply_to)
else
_e -> object
end
end
def set_reply_to_uri(obj), do: obj
#
# # Prepares the object of an outgoing create activity.
def prepare_object(object) do
object
# |> set_sensitive
|> add_hashtags
|> add_mention_tags
# |> add_emoji_tags
|> add_attributed_to
# |> prepare_attachments
|> set_reply_to_uri
end
@doc """
internal -> Mastodon
"""
def prepare_outgoing(%{"type" => "Create", "object" => %{"type" => "Note"} = object} = data) do
Logger.debug("Prepare outgoing for a note creation")
object =
object
|> prepare_object
data =
data
|> Map.put("object", object)
|> Map.merge(Utils.make_json_ld_header())
Logger.debug("Finished prepare outgoing for a note creation")
{:ok, data}
end
def prepare_outgoing(%{"type" => _type} = data) do
data =
data
|> Map.merge(Utils.make_json_ld_header())
{:ok, data}
end
# def prepare_outgoing(%Event{} = event) do
# event =
# event
# |> Map.from_struct()
# |> Map.drop([:__meta__])
# |> Map.put(:"@context", "https://www.w3.org/ns/activitystreams")
# |> prepare_object
# {:ok, event}
# end
# def prepare_outgoing(%Comment{} = comment) do
# comment =
# comment
# |> Map.from_struct()
# |> Map.drop([:__meta__])
# |> Map.put(:"@context", "https://www.w3.org/ns/activitystreams")
# |> prepare_object
# {:ok, comment}
# end
#
# def maybe_fix_object_url(data) do
# if is_binary(data["object"]) and not String.starts_with?(data["object"], "http") do
# case ActivityPub.fetch_object_from_id(data["object"]) do
# {:ok, relative_object} ->
# if relative_object.data["external_url"] do
# data =
# data
# |> Map.put("object", relative_object.data["external_url"])
# else
# data
# end
#
# e ->
# Logger.error("Couldn't fetch #{data["object"]} #{inspect(e)}")
# data
# end
# else
# data
# end
# end
#
def add_hashtags(object) do
tags =
(object["tag"] || [])
|> Enum.map(fn tag ->
%{
"href" => MobilizonWeb.Endpoint.url() <> "/tags/#{tag}",
"name" => "##{tag}",
"type" => "Hashtag"
}
end)
object
|> Map.put("tag", tags)
end
def add_mention_tags(object) do
recipients =
(object["to"] ++ (object["cc"] || [])) -- ["https://www.w3.org/ns/activitystreams#Public"]
mentions =
recipients
|> Enum.filter(& &1)
|> Enum.map(fn url ->
case Actors.get_actor_by_url(url) do
{:ok, actor} -> actor
_ -> nil
end
end)
|> Enum.filter(& &1)
|> Enum.map(fn actor ->
%{"type" => "Mention", "href" => actor.url, "name" => "@#{actor.preferred_username}"}
end)
tags = object["tag"] || []
object
|> Map.put("tag", tags ++ mentions)
end
#
# # TODO: we should probably send mtime instead of unix epoch time for updated
# def add_emoji_tags(object) do
# tags = object["tag"] || []
# emoji = object["emoji"] || []
#
# out =
# emoji
# |> Enum.map(fn {name, url} ->
# %{
# "icon" => %{"url" => url, "type" => "Image"},
# "name" => ":" <> name <> ":",
# "type" => "Emoji",
# "updated" => "1970-01-01T00:00:00Z",
# "id" => url
# }
# end)
#
# object
# |> Map.put("tag", tags ++ out)
# end
#
#
# def set_sensitive(object) do
# tags = object["tag"] || []
# Map.put(object, "sensitive", "nsfw" in tags)
# end
#
def add_attributed_to(object) do
attributed_to = object["attributedTo"] || object["actor"]
object |> Map.put("attributedTo", attributed_to)
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
@spec fetch_obj_helper(map() | String.t()) :: Event.t() | Comment.t() | Actor.t() | any()
def fetch_obj_helper(object) do
Logger.debug("Fetching object #{inspect(object)}")
case object |> Utils.get_url() |> ActivityPub.fetch_object_from_url() do
{:ok, object} ->
{:ok, object}
err ->
Logger.info("Error while fetching #{inspect(object)}")
{:error, err}
end
end
def fetch_obj_helper_as_activity_streams(object) do
with {:ok, object} <- fetch_obj_helper(object) do
{:ok, Mobilizon.Service.ActivityPub.Convertible.model_to_as(object)}
end
end
end