# Pleroma: A lightweight social networking server # Copyright © 2017-2019 Pleroma Authors <https://pleroma.social/> # SPDX-License-Identifier: AGPL-3.0-only defmodule Pleroma.Web.ActivityPub.Utils do alias Pleroma.{Repo, Web, Object, Activity, User, Notification} alias Pleroma.Web.Router.Helpers alias Pleroma.Web.Endpoint alias Ecto.{Changeset, UUID} import Ecto.Query require Logger @supported_object_types ["Article", "Note", "Video", "Page"] # Some implementations send the actor URI as the actor field, others send the entire actor object, # so figure out what the actor's URI is based on what we have. def get_ap_id(object) do case object do %{"id" => id} -> id id -> id end end def normalize_params(params) do Map.put(params, "actor", get_ap_id(params["actor"])) end def determine_explicit_mentions(%{"tag" => tag} = _object) when is_list(tag) do tag |> Enum.filter(fn x -> is_map(x) end) |> Enum.filter(fn x -> x["type"] == "Mention" end) |> Enum.map(fn x -> x["href"] end) end def determine_explicit_mentions(%{"tag" => tag} = object) when is_map(tag) do Map.put(object, "tag", [tag]) |> determine_explicit_mentions() end def determine_explicit_mentions(_), do: [] defp recipient_in_collection(ap_id, coll) when is_binary(coll), do: ap_id == coll defp recipient_in_collection(ap_id, coll) when is_list(coll), do: ap_id in coll defp recipient_in_collection(_, _), do: false def recipient_in_message(ap_id, params) do cond do recipient_in_collection(ap_id, params["to"]) -> true recipient_in_collection(ap_id, params["cc"]) -> true recipient_in_collection(ap_id, params["bto"]) -> true recipient_in_collection(ap_id, params["bcc"]) -> true # if the message is unaddressed at all, then assume it is directly addressed # to the recipient !params["to"] && !params["cc"] && !params["bto"] && !params["bcc"] -> true true -> false end end defp extract_list(target) when is_binary(target), do: [target] defp extract_list(lst) when is_list(lst), do: lst defp extract_list(_), do: [] def maybe_splice_recipient(ap_id, params) do need_splice = !recipient_in_collection(ap_id, params["to"]) && !recipient_in_collection(ap_id, params["cc"]) cc_list = extract_list(params["cc"]) if need_splice do params |> Map.put("cc", [ap_id | cc_list]) else params end end def make_json_ld_header do %{ "@context" => [ "https://www.w3.org/ns/activitystreams", "#{Web.base_url()}/schemas/litepub-0.1.jsonld" ] } end def make_date do DateTime.utc_now() |> DateTime.to_iso8601() end def generate_activity_id do generate_id("activities") end def generate_context_id do generate_id("contexts") end def generate_object_id do Helpers.o_status_url(Endpoint, :object, UUID.generate()) end def generate_id(type) do "#{Web.base_url()}/#{type}/#{UUID.generate()}" end def get_notified_from_object(%{"type" => type} = object) when type in @supported_object_types do fake_create_activity = %{ "to" => object["to"], "cc" => object["cc"], "type" => "Create", "object" => object } Notification.get_notified_from_activity(%Activity{data: fake_create_activity}, false) end def get_notified_from_object(object) do Notification.get_notified_from_activity(%Activity{data: object}, false) end def create_context(context) do context = context || generate_id("contexts") changeset = Object.context_mapping(context) case Repo.insert(changeset) do {:ok, object} -> object # This should be solved by an upsert, but it seems ecto # has problems accessing the constraint inside the jsonb. {:error, _} -> Object.get_cached_by_ap_id(context) end end @doc """ Enqueues an activity for federation if it's local """ def maybe_federate(%Activity{local: true} = activity) do priority = case activity.data["type"] do "Delete" -> 10 "Create" -> 1 _ -> 5 end Pleroma.Web.Federator.enqueue(:publish, activity, priority) :ok end def maybe_federate(_), do: :ok @doc """ Adds an id and a published data if they aren't there, also adds it to an included object """ def lazy_put_activity_defaults(map) do %{data: %{"id" => context}, id: context_id} = create_context(map["context"]) map = map |> Map.put_new_lazy("id", &generate_activity_id/0) |> Map.put_new_lazy("published", &make_date/0) |> Map.put_new("context", context) |> Map.put_new("context_id", context_id) if is_map(map["object"]) do object = lazy_put_object_defaults(map["object"], map) %{map | "object" => object} else map end end @doc """ Adds an id and published date if they aren't there. """ def lazy_put_object_defaults(map, activity \\ %{}) do map |> Map.put_new_lazy("id", &generate_object_id/0) |> Map.put_new_lazy("published", &make_date/0) |> Map.put_new("context", activity["context"]) |> Map.put_new("context_id", activity["context_id"]) end @doc """ Inserts a full object if it is contained in an activity. """ def insert_full_object(%{"object" => %{"type" => type} = object_data}) when is_map(object_data) and type in @supported_object_types do with {:ok, _} <- Object.create(object_data) do :ok end end def insert_full_object(_), do: :ok def update_object_in_activities(%{data: %{"id" => id}} = object) do # TODO # Update activities that already had this. Could be done in a seperate process. # Alternatively, just don't do this and fetch the current object each time. Most # could probably be taken from cache. relevant_activities = Activity.all_by_object_ap_id(id) Enum.map(relevant_activities, fn activity -> new_activity_data = activity.data |> Map.put("object", object.data) changeset = Changeset.change(activity, data: new_activity_data) Repo.update(changeset) end) end #### Like-related helpers @doc """ Returns an existing like if a user already liked an object """ def get_existing_like(actor, %{data: %{"id" => id}}) do query = from( activity in Activity, where: fragment("(?)->>'actor' = ?", activity.data, ^actor), # this is to use the index where: fragment( "coalesce((?)->'object'->>'id', (?)->>'object') = ?", activity.data, activity.data, ^id ), where: fragment("(?)->>'type' = 'Like'", activity.data) ) Repo.one(query) end @doc """ Returns like activities targeting an object """ def get_object_likes(%{data: %{"id" => id}}) do query = from( activity in Activity, # this is to use the index where: fragment( "coalesce((?)->'object'->>'id', (?)->>'object') = ?", activity.data, activity.data, ^id ), where: fragment("(?)->>'type' = 'Like'", activity.data) ) Repo.all(query) end def make_like_data(%User{ap_id: ap_id} = actor, %{data: %{"id" => id}} = object, activity_id) do data = %{ "type" => "Like", "actor" => ap_id, "object" => id, "to" => [actor.follower_address, object.data["actor"]], "cc" => ["https://www.w3.org/ns/activitystreams#Public"], "context" => object.data["context"] } if activity_id, do: Map.put(data, "id", activity_id), else: data end def update_element_in_object(property, element, object) do with new_data <- object.data |> Map.put("#{property}_count", length(element)) |> Map.put("#{property}s", element), changeset <- Changeset.change(object, data: new_data), {:ok, object} <- Repo.update(changeset), _ <- update_object_in_activities(object) do {:ok, object} end end def update_likes_in_object(likes, object) do update_element_in_object("like", likes, object) end def add_like_to_object(%Activity{data: %{"actor" => actor}}, object) do likes = if is_list(object.data["likes"]), do: object.data["likes"], else: [] with likes <- [actor | likes] |> Enum.uniq() do update_likes_in_object(likes, object) end end def remove_like_from_object(%Activity{data: %{"actor" => actor}}, object) do likes = if is_list(object.data["likes"]), do: object.data["likes"], else: [] with likes <- likes |> List.delete(actor) do update_likes_in_object(likes, object) end end #### Follow-related helpers @doc """ Updates a follow activity's state (for locked accounts). """ def update_follow_state(%Activity{} = activity, state) do with new_data <- activity.data |> Map.put("state", state), changeset <- Changeset.change(activity, data: new_data), {:ok, activity} <- Repo.update(changeset) do {:ok, activity} end end @doc """ Makes a follow activity data for the given follower and followed """ def make_follow_data( %User{ap_id: follower_id}, %User{ap_id: followed_id} = _followed, activity_id ) do data = %{ "type" => "Follow", "actor" => follower_id, "to" => [followed_id], "cc" => ["https://www.w3.org/ns/activitystreams#Public"], "object" => followed_id, "state" => "pending" } data = if activity_id, do: Map.put(data, "id", activity_id), else: data data end def fetch_latest_follow(%User{ap_id: follower_id}, %User{ap_id: followed_id}) do query = from( activity in Activity, where: fragment( "? ->> 'type' = 'Follow'", activity.data ), where: activity.actor == ^follower_id, where: fragment( "? @> ?", activity.data, ^%{object: followed_id} ), order_by: [desc: :id], limit: 1 ) Repo.one(query) end #### Announce-related helpers @doc """ Retruns an existing announce activity if the notice has already been announced """ def get_existing_announce(actor, %{data: %{"id" => id}}) do query = from( activity in Activity, where: activity.actor == ^actor, # this is to use the index where: fragment( "coalesce((?)->'object'->>'id', (?)->>'object') = ?", activity.data, activity.data, ^id ), where: fragment("(?)->>'type' = 'Announce'", activity.data) ) Repo.one(query) end @doc """ Make announce activity data for the given actor and object """ # for relayed messages, we only want to send to subscribers def make_announce_data( %User{ap_id: ap_id} = user, %Object{data: %{"id" => id}} = object, activity_id, false ) do data = %{ "type" => "Announce", "actor" => ap_id, "object" => id, "to" => [user.follower_address], "cc" => [], "context" => object.data["context"] } if activity_id, do: Map.put(data, "id", activity_id), else: data end def make_announce_data( %User{ap_id: ap_id} = user, %Object{data: %{"id" => id}} = object, activity_id, true ) do data = %{ "type" => "Announce", "actor" => ap_id, "object" => id, "to" => [user.follower_address, object.data["actor"]], "cc" => ["https://www.w3.org/ns/activitystreams#Public"], "context" => object.data["context"] } if activity_id, do: Map.put(data, "id", activity_id), else: data end @doc """ Make unannounce activity data for the given actor and object """ def make_unannounce_data( %User{ap_id: ap_id} = user, %Activity{data: %{"context" => context}} = activity, activity_id ) do data = %{ "type" => "Undo", "actor" => ap_id, "object" => activity.data, "to" => [user.follower_address, activity.data["actor"]], "cc" => ["https://www.w3.org/ns/activitystreams#Public"], "context" => context } if activity_id, do: Map.put(data, "id", activity_id), else: data end def make_unlike_data( %User{ap_id: ap_id} = user, %Activity{data: %{"context" => context}} = activity, activity_id ) do data = %{ "type" => "Undo", "actor" => ap_id, "object" => activity.data, "to" => [user.follower_address, activity.data["actor"]], "cc" => ["https://www.w3.org/ns/activitystreams#Public"], "context" => context } if activity_id, do: Map.put(data, "id", activity_id), else: data end def add_announce_to_object( %Activity{ data: %{"actor" => actor, "cc" => ["https://www.w3.org/ns/activitystreams#Public"]} }, object ) do announcements = if is_list(object.data["announcements"]), do: object.data["announcements"], else: [] with announcements <- [actor | announcements] |> Enum.uniq() do update_element_in_object("announcement", announcements, object) end end def add_announce_to_object(_, object), do: {:ok, object} def remove_announce_from_object(%Activity{data: %{"actor" => actor}}, object) do announcements = if is_list(object.data["announcements"]), do: object.data["announcements"], else: [] with announcements <- announcements |> List.delete(actor) do update_element_in_object("announcement", announcements, object) end end #### Unfollow-related helpers def make_unfollow_data(follower, followed, follow_activity, activity_id) do data = %{ "type" => "Undo", "actor" => follower.ap_id, "to" => [followed.ap_id], "object" => follow_activity.data } if activity_id, do: Map.put(data, "id", activity_id), else: data end #### Block-related helpers def fetch_latest_block(%User{ap_id: blocker_id}, %User{ap_id: blocked_id}) do query = from( activity in Activity, where: fragment( "? ->> 'type' = 'Block'", activity.data ), where: activity.actor == ^blocker_id, where: fragment( "? @> ?", activity.data, ^%{object: blocked_id} ), order_by: [desc: :id], limit: 1 ) Repo.one(query) end def make_block_data(blocker, blocked, activity_id) do data = %{ "type" => "Block", "actor" => blocker.ap_id, "to" => [blocked.ap_id], "object" => blocked.ap_id } if activity_id, do: Map.put(data, "id", activity_id), else: data end def make_unblock_data(blocker, blocked, block_activity, activity_id) do data = %{ "type" => "Undo", "actor" => blocker.ap_id, "to" => [blocked.ap_id], "object" => block_activity.data } if activity_id, do: Map.put(data, "id", activity_id), else: data end #### Create-related helpers def make_create_data(params, additional) do published = params.published || make_date() %{ "type" => "Create", "to" => params.to |> Enum.uniq(), "actor" => params.actor.ap_id, "object" => params.object, "published" => published, "context" => params.context } |> Map.merge(additional) end end