# 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 Ecto.Changeset alias Ecto.UUID alias Pleroma.Activity alias Pleroma.Notification alias Pleroma.Object alias Pleroma.Repo alias Pleroma.User alias Pleroma.Web alias Pleroma.Web.ActivityPub.Visibility alias Pleroma.Web.Endpoint alias Pleroma.Web.Router.Helpers import Ecto.Query require Logger @supported_object_types ["Article", "Note", "Video", "Page", "Question", "Answer"] @supported_report_states ~w(open closed resolved) @valid_visibilities ~w(public unlisted private direct) # 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(%{"id" => id} = _), do: id def get_ap_id(id), do: id 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(%User{ap_id: ap_id} = recipient, %User{} = actor, 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 # if the message is sent from somebody the user is following, then assume it # is addressed to the recipient User.following?(recipient, actor) -> 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", %{ "@language" => "und" } ] } 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") # Ecto has problems accessing the constraint inside the jsonb, # so we explicitly check for the existed object before insert object = Object.get_cached_by_ap_id(context) with true <- is_nil(object), changeset <- Object.context_mapping(context), {:ok, inserted_object} <- Repo.insert(changeset) do inserted_object else _ -> object end end @doc """ Enqueues an activity for federation if it's local """ def maybe_federate(%Activity{local: true} = activity) do if Pleroma.Config.get!([:instance, :federating]) do priority = case activity.data["type"] do "Delete" -> 10 "Create" -> 1 _ -> 5 end Pleroma.Web.Federator.publish(activity, priority) end :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, fake \\ false) do map = unless fake do %{data: %{"id" => context}, id: context_id} = create_context(map["context"]) 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) else map |> Map.put_new("id", "pleroma:fakeid") |> Map.put_new_lazy("published", &make_date/0) |> Map.put_new("context", "pleroma:fakecontext") |> Map.put_new("context_id", -1) end if is_map(map["object"]) do object = lazy_put_object_defaults(map["object"], map, fake) %{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 \\ %{}, fake) def lazy_put_object_defaults(map, activity, true = _fake) do map |> Map.put_new_lazy("published", &make_date/0) |> Map.put_new("id", "pleroma:fake_object_id") |> Map.put_new("context", activity["context"]) |> Map.put_new("fake", true) |> Map.put_new("context_id", activity["context_id"]) end def lazy_put_object_defaults(map, activity, _fake) 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} = map) when is_map(object_data) and type in @supported_object_types do with {:ok, object} <- Object.create(object_data) do map = map |> Map.put("object", object.data["id"]) {:ok, map, object} end end def insert_full_object(map), do: {:ok, map, nil} 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.get_all_create_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: %{"actor" => object_actor_id, "id" => id}} = object, activity_id ) do object_actor = User.get_cached_by_ap_id(object_actor_id) to = if Visibility.is_public?(object) do [actor.follower_address, object.data["actor"]] else [object.data["actor"]] end cc = (object.data["to"] ++ (object.data["cc"] || [])) |> List.delete(actor.ap_id) |> List.delete(object_actor.follower_address) data = %{ "type" => "Like", "actor" => ap_id, "object" => id, "to" => to, "cc" => cc, "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} <- Object.update_and_set_cache(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_for_all( %Activity{data: %{"actor" => actor, "object" => object}} = activity, state ) do try do Ecto.Adapters.SQL.query!( Repo, "UPDATE activities SET data = jsonb_set(data, '{state}', $1) WHERE data->>'type' = 'Follow' AND data->>'actor' = $2 AND data->>'object' = $3 AND data->>'state' = 'pending'", [state, actor, object] ) activity = Activity.get_by_id(activity.id) {:ok, activity} rescue e -> {:error, e} end end 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, # this is to use the index where: fragment( "coalesce((?)->'object'->>'id', (?)->>'object') = ?", activity.data, activity.data, ^followed_id ), order_by: [fragment("? desc nulls last", activity.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, # this is to use the index where: fragment( "coalesce((?)->'object'->>'id', (?)->>'object') = ?", activity.data, activity.data, ^blocked_id ), order_by: [fragment("? desc nulls last", activity.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 #### Flag-related helpers def make_flag_data(params, additional) do status_ap_ids = Enum.map(params.statuses || [], fn %Activity{} = act -> act.data["id"] act when is_map(act) -> act["id"] act when is_binary(act) -> act end) object = [params.account.ap_id] ++ status_ap_ids %{ "type" => "Flag", "actor" => params.actor.ap_id, "content" => params.content, "object" => object, "context" => params.context, "state" => "open" } |> Map.merge(additional) end @doc """ Fetches the OrderedCollection/OrderedCollectionPage from `from`, limiting the amount of pages fetched after the first one to `pages_left` pages. If the amount of pages is higher than the collection has, it returns whatever was there. """ def fetch_ordered_collection(from, pages_left, acc \\ []) do with {:ok, response} <- Tesla.get(from), {:ok, collection} <- Jason.decode(response.body) do case collection["type"] do "OrderedCollection" -> # If we've encountered the OrderedCollection and not the page, # just call the same function on the page address fetch_ordered_collection(collection["first"], pages_left) "OrderedCollectionPage" -> if pages_left > 0 do # There are still more pages if Map.has_key?(collection, "next") do # There are still more pages, go deeper saving what we have into the accumulator fetch_ordered_collection( collection["next"], pages_left - 1, acc ++ collection["orderedItems"] ) else # No more pages left, just return whatever we already have acc ++ collection["orderedItems"] end else # Got the amount of pages needed, add them all to the accumulator acc ++ collection["orderedItems"] end _ -> {:error, "Not an OrderedCollection or OrderedCollectionPage"} end end end #### Report-related helpers def update_report_state(%Activity{} = activity, state) when state in @supported_report_states do with new_data <- Map.put(activity.data, "state", state), changeset <- Changeset.change(activity, data: new_data), {:ok, activity} <- Repo.update(changeset) do {:ok, activity} end end def update_report_state(_, _), do: {:error, "Unsupported state"} def update_activity_visibility(activity, visibility) when visibility in @valid_visibilities do [to, cc, recipients] = activity |> get_updated_targets(visibility) |> Enum.map(&Enum.uniq/1) object_data = activity.object.data |> Map.put("to", to) |> Map.put("cc", cc) {:ok, object} = activity.object |> Object.change(%{data: object_data}) |> Object.update_and_set_cache() activity_data = activity.data |> Map.put("to", to) |> Map.put("cc", cc) activity |> Map.put(:object, object) |> Activity.change(%{data: activity_data, recipients: recipients}) |> Repo.update() end def update_activity_visibility(_, _), do: {:error, "Unsupported visibility"} defp get_updated_targets( %Activity{data: %{"to" => to} = data, recipients: recipients}, visibility ) do cc = Map.get(data, "cc", []) follower_address = User.get_cached_by_ap_id(data["actor"]).follower_address public = "https://www.w3.org/ns/activitystreams#Public" case visibility do "public" -> to = [public | List.delete(to, follower_address)] cc = [follower_address | List.delete(cc, public)] recipients = [public | recipients] [to, cc, recipients] "private" -> to = [follower_address | List.delete(to, public)] cc = List.delete(cc, public) recipients = List.delete(recipients, public) [to, cc, recipients] "unlisted" -> to = [follower_address | List.delete(to, public)] cc = [public | List.delete(cc, follower_address)] recipients = recipients ++ [follower_address, public] [to, cc, recipients] _ -> [to, cc, recipients] end end def get_existing_votes(actor, %{data: %{"id" => id}}) do query = from( [activity, object: object] in Activity.with_preloaded_object(Activity), where: fragment("(?)->>'type' = 'Create'", activity.data), where: fragment("(?)->>'actor' = ?", activity.data, ^actor), where: fragment( "(?)->>'inReplyTo' = ?", object.data, ^to_string(id) ), where: fragment("(?)->>'type' = 'Answer'", object.data) ) Repo.all(query) end end